Add new H5R API that abstracts object, region and attribute reference types

Also support references to external files

Add new H5T_REF type and type conversion routines

Support conversion from H5T_REF_OBJ/DSET_REG to H5T_REF

Add H5Treclaim() API to reclaim memory of vlen/reference types

Deprecate H5Dvlen_reclaim()

Fix H5T_vlen_reclaim() and H5T_reclaim() to use private callback

Add H5T_ref_reclaim()

Move previous H5R APIs to H5Rdeprec.c

Clean up H5Ocopy

Separate H5O_copy_expand_ref() to H5Ocopy_ref()

Add support for copying new reference types

Clean up deprecated routines to go through VOL and same code path

Fix return codes in existing trefer.c test

Rename trefer.c to trefer_deprec.c

trefer.c is for new references

Add performance test for trefer

Add additional obj_copy_ref test

Make use of tokens and blobs to store references

Skip blob encoding for object references

Start adding new reference examples

54 files changed, 10097 insertions, 1953 deletions

diff --git a/MANIFEST b/MANIFEST
index 5e7caff..a1b3b4a 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -167,8 +167,10 @@
 ./examples/h5_select.c
 ./examples/h5_attribute.c
 ./examples/h5_mount.c
-./examples/h5_reference.c
-./examples/h5_ref2reg.c
+./examples/h5_ref_compat.c
+./examples/h5_ref_extern.c
+./examples/h5_reference_deprec.c
+./examples/h5_ref2reg_deprec.c
 ./examples/h5_shared_mesg.c
 ./examples/ph5example.c
 ./examples/h5_vds.c
@@ -782,6 +784,7 @@
 ./src/H5Ochunk.c
 ./src/H5Ocont.c
 ./src/H5Ocopy.c
+./src/H5Ocopy_ref.c
 ./src/H5Odbg.c
 ./src/H5Odeprec.c
 ./src/H5Odrvinfo.c
@@ -911,6 +914,7 @@
 ./src/H5Tprecis.c
 ./src/H5Tprivate.h
 ./src/H5Tpublic.h
+./src/H5Tref.c
 ./src/H5Tstrpad.c
 ./src/H5Tvisit.c
 ./src/H5Tvlen.c
@@ -1107,6 +1111,7 @@
 ./test/null_vol_connector.h
 ./test/ohdr.c
 ./test/objcopy.c
+./test/objcopy_ref.c
 ./test/page_buffer.c
 ./test/paged_nopersist.h5
 ./test/paged_persist.h5
@@ -1176,6 +1181,7 @@
 ./test/tmtimeo.h5
 ./test/ttime.c
 ./test/trefer.c
+./test/trefer_deprec.c
 ./test/trefstr.c
 ./test/tselect.c
 ./test/tsizeslheap.h5
diff --git a/bin/trace b/bin/trace
index fe0443d..3cae0a4 100755
--- a/bin/trace
+++ b/bin/trace
@@ -78,7 +78,9 @@ $Source = "";
                "off_t"                      => "o",
                "H5O_type_t"                 => "Ot",
                "H5P_class_t"                => "p",
-               "hobj_ref_t"                 => "r",
+               "hobj_ref_t"                 => "Ro",
+               "hdset_reg_ref_t"            => "Rd",
+               "H5R_ref_t"                  => "Rr",
                "H5R_type_t"                 => "Rt",
                "char"                       => "s",
                "unsigned char"              => "s",
diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt
index 6e1f79d..9f42f95 100644
--- a/examples/CMakeLists.txt
+++ b/examples/CMakeLists.txt
@@ -23,9 +23,11 @@ set (examples
     h5_select
     h5_attribute
     h5_mount
-    h5_reference
+    h5_ref_extern
+    h5_ref_compat
+    h5_reference_deprec
     h5_drivers
-    h5_ref2reg
+    h5_ref2reg_deprec
     h5_extlink
     h5_elink_unix2win
     h5_shared_mesg
diff --git a/examples/Makefile.am b/examples/Makefile.am
index 554ee44..131842c 100644
--- a/examples/Makefile.am
+++ b/examples/Makefile.am
@@ -34,8 +34,9 @@ INSTALL_TOP_FILES = README
 EXAMPLE_PROG = h5_write h5_read h5_extend_write h5_chunk_read h5_compound \
             h5_crtgrpd h5_subset h5_cmprss h5_rdwt h5_crtgrpar h5_extend \
             h5_crtatt h5_crtgrp h5_crtdat \
-            h5_group h5_select h5_attribute h5_mount h5_reference h5_drivers \
-            h5_ref2reg h5_extlink h5_elink_unix2win h5_shared_mesg h5_vds h5_vds-exc \
+            h5_group h5_select h5_attribute h5_mount h5_reference_deprec h5_drivers \
+            h5_ref_extern h5_ref_compat \
+            h5_ref2reg_deprec h5_extlink h5_elink_unix2win h5_shared_mesg h5_vds h5_vds-exc \
             h5_vds-exclim h5_vds-eiger h5_vds-simpleIO h5_vds-percival \
             h5_vds-percival-unlim h5_vds-percival-unlim-maxmin
 TEST_SCRIPT=testh5cc.sh 
@@ -47,8 +48,9 @@ INSTALL_FILES = h5_write.c h5_read.c h5_extend_write.c h5_chunk_read.c   \
             h5_crtgrpd.c h5_subset.c h5_cmprss.c h5_rdwt.c h5_crtgrpar.c \
             h5_extend.c h5_crtatt.c h5_crtgrp.c h5_crtdat.c \
             h5_compound.c h5_group.c h5_select.c h5_attribute.c h5_mount.c \
-            h5_reference.c h5_drivers.c h5_extlink.c h5_elink_unix2win.c   \
-            h5_ref2reg.c h5_shared_mesg.c ph5example.c h5_vds.c h5_vds-exc.c \
+            h5_reference_deprec.c h5_drivers.c h5_extlink.c h5_elink_unix2win.c   \
+            h5_ref_extern.c h5_ref_compat.c \
+            h5_ref2reg_deprec.c h5_shared_mesg.c ph5example.c h5_vds.c h5_vds-exc.c \
             h5_vds-exclim.c h5_vds-eiger.c h5_vds-simpleIO.c h5_vds-percival.c \
             h5_vds-percival-unlim.c h5_vds-percival-unlim-maxmin.c
 
@@ -111,8 +113,10 @@ h5_read: $(srcdir)/h5_read.c
 h5_select: $(srcdir)/h5_select.c
 h5_attribute: $(srcdir)/h5_attribute.c
 h5_mount: $(srcdir)/h5_mount.c
-h5_reference: $(srcdir)/h5_reference.c
-h5_ref2reg: $(srcdir)/h5_ref2reg.c
+h5_ref_compat: $(srcdir)/h5_ref_compat.c
+h5_ref_extern: $(srcdir)/h5_ref_extern.c
+h5_reference_deprec: $(srcdir)/h5_reference_deprec.c
+h5_ref2reg_deprec: $(srcdir)/h5_ref2reg_deprec.c
 h5_drivers: $(srcdir)/h5_drivers.c
 ph5example: $(srcdir)/ph5example.c
 h5_dtransform: $(srcdir)/h5_dtransform.c
diff --git a/examples/h5_ref2reg.c b/examples/h5_ref2reg_deprec.c
index dc2964c..dc2964c 100644
--- a/examples/h5_ref2reg.c
+++ b/examples/h5_ref2reg_deprec.c
diff --git a/examples/h5_ref_compat.c b/examples/h5_ref_compat.c
new file mode 100644
index 0000000..a1fbf96
--- /dev/null
+++ b/examples/h5_ref_compat.c
@@ -0,0 +1,90 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the COPYING file, which can be found at the root of the source code       *
+ * distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.  *
+ * If you do not have access to either file, you may request a copy from     *
+ * help@hdfgroup.org.                                                        *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+ /*
+  * The example below illustrates the use of the new API with a file that was
+  * written using the old-style reference API, showing how one can take
+  * advantage of the automatic type conversion from old reference type to new
+  * reference type.
+  */
+
+#include <stdlib.h>
+
+#include "hdf5.h"
+#include <assert.h>
+
+#define H5FILE_NAME "refer_deprec.h5"
+
+#define NDIMS    1    /* Number of dimensions */
+#define BUF_SIZE 4    /* Size of example buffer */
+#define NREFS    1    /* Number of references */
+
+int
+main(void) {
+    hid_t file1, dset1, space1;
+    hsize_t dset1_dims[NDIMS] = { BUF_SIZE };
+    int dset_buf[BUF_SIZE];
+
+    hid_t dset2, space2;
+    hsize_t dset2_dims[NDIMS] = { NREFS };
+    hobj_ref_t ref_buf[NREFS] = { 0 };
+    H5R_ref_t new_ref_buf[NREFS] = { 0 };
+    H5O_type_t obj_type;
+    int i;
+
+    for (i = 0; i < BUF_SIZE; i++)
+        dset_buf[i] = i;
+
+    /* Create file with one dataset and close it */
+    file1 = H5Fcreate(H5FILE_NAME, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+
+    space1 = H5Screate_simple(NDIMS, dset1_dims, NULL);
+    dset1 = H5Dcreate2(file1, "dataset1", H5T_NATIVE_INT, space1, H5P_DEFAULT,
+                       H5P_DEFAULT, H5P_DEFAULT);
+    H5Dwrite(dset1, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, dset_buf);
+    H5Dclose(dset1);
+    H5Sclose(space1);
+
+    /**
+     * Create reference to dataset1 with deprecated API
+     * (reminder: there is no destroy call for those references)
+     */
+    H5Rcreate(&ref_buf[0], file1, "dataset1", H5R_OBJECT, H5I_INVALID_HID);
+
+    /* Store reference in separate dataset using deprecated reference type */
+    space2 = H5Screate_simple(NDIMS, dset2_dims, NULL);
+    dset2 = H5Dcreate2(file1, "references", H5T_STD_REF_OBJ, space2, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    H5Dwrite(dset2, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, ref_buf);
+    H5Dclose(dset2);
+    H5Sclose(space2);
+    H5Fclose(file1);
+
+    /* Read reference from file using new reference type */
+    file1 = H5Fopen(H5FILE_NAME, H5F_ACC_RDONLY, H5P_DEFAULT);
+    dset2 = H5Dopen2(file1, "references", H5P_DEFAULT);
+    H5Dread(dset2, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, new_ref_buf);
+    H5Dclose(dset2);
+
+    /* Access reference and read dataset data through new API */
+    assert(H5Rget_type((const H5R_ref_t *)&new_ref_buf[0]) == H5R_OBJECT2);
+    H5Rget_obj_type3((const H5R_ref_t *)&new_ref_buf[0], H5P_DEFAULT, &obj_type);
+    assert(obj_type == H5O_TYPE_DATASET);
+    dset1 = H5Ropen_object((const H5R_ref_t *)&new_ref_buf[0], H5P_DEFAULT, H5P_DEFAULT);
+    H5Dread(dset1, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, dset_buf);
+    H5Dclose(dset1);
+    H5Rdestroy(&new_ref_buf[0]);
+
+    for (i = 0; i < BUF_SIZE; i++)
+        assert(dset_buf[i] == i);
+    return 0;
+}
+
diff --git a/examples/h5_ref_extern.c b/examples/h5_ref_extern.c
new file mode 100644
index 0000000..4327a06
--- /dev/null
+++ b/examples/h5_ref_extern.c
@@ -0,0 +1,94 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the COPYING file, which can be found at the root of the source code       *
+ * distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.  *
+ * If you do not have access to either file, you may request a copy from     *
+ * help@hdfgroup.org.                                                        *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+ /*
+  * The example below illustrates the use of the new API with files that are
+  * opened read-only. Created references to the objects in that file are
+  * stored into a separate file, and accessed from that file, without the user
+  * explicitly opening the original file that was referenced. 
+  */
+
+#include <stdlib.h>
+
+#include "hdf5.h"
+#include <assert.h>
+
+#define H5FILE_NAME1 "refer_extern1.h5"
+#define H5FILE_NAME2 "refer_extern2.h5"
+
+#define NDIMS    1    /* Number of dimensions */
+#define BUF_SIZE 4    /* Size of example buffer */
+#define NREFS    1    /* Number of references */
+
+int
+main(void) {
+    hid_t file1, dset1, space1;
+    hsize_t dset1_dims[NDIMS] = { BUF_SIZE };
+    int dset_buf[BUF_SIZE];
+
+    hid_t file2, dset2, space2;
+    hsize_t dset2_dims[NDIMS] = { NREFS };
+    H5R_ref_t ref_buf[NREFS] = { 0 };
+    H5O_type_t obj_type;
+    int i;
+
+    for (i = 0; i < BUF_SIZE; i++)
+        dset_buf[i] = i;
+
+    /* Create file with one dataset and close it */
+    file1 = H5Fcreate(H5FILE_NAME1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    space1 = H5Screate_simple(NDIMS, dset1_dims, NULL);
+    dset1 = H5Dcreate2(file1, "dataset1", H5T_NATIVE_INT, space1, H5P_DEFAULT,
+                       H5P_DEFAULT, H5P_DEFAULT);
+    H5Dwrite(dset1, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, dset_buf);
+    H5Dclose(dset1);
+    H5Sclose(space1);
+    H5Fclose(file1);
+
+    /* Create reference to dataset1 in "refer_extern1.h5" */
+    file1 = H5Fopen(H5FILE_NAME1, H5F_ACC_RDONLY, H5P_DEFAULT);
+    H5Rcreate_object(file1, "dataset1", &ref_buf[0]);
+    H5Fclose(file1);
+
+    /* Store reference in dataset in separate file "refer_extern2.h5" */
+    file2 = H5Fcreate(H5FILE_NAME2, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    space2 = H5Screate_simple(NDIMS, dset2_dims, NULL);
+    dset2 = H5Dcreate2(file2, "references", H5T_STD_REF, space2, H5P_DEFAULT,
+                       H5P_DEFAULT, H5P_DEFAULT);
+    H5Dwrite(dset2, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, ref_buf);
+    H5Dclose(dset2);
+    H5Sclose(space2);
+    H5Fclose(file2);
+    H5Rdestroy(&ref_buf[0]);
+
+    /* Read reference back from "refer_extern2.h5" */
+    file2 = H5Fopen(H5FILE_NAME2, H5F_ACC_RDONLY, H5P_DEFAULT);
+    dset2 = H5Dopen2(file2, "references", H5P_DEFAULT);
+    H5Dread(dset2, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, ref_buf);
+    H5Dclose(dset2);
+    H5Fclose(file2);
+
+    /* Access reference and read dataset data without opening original file */
+    assert(H5Rget_type((const H5R_ref_t *)&ref_buf[0]) == H5R_OBJECT2);
+    H5Rget_obj_type3((const H5R_ref_t *)&ref_buf[0], H5P_DEFAULT, &obj_type);
+    assert(obj_type == H5O_TYPE_DATASET);
+    dset1 = H5Ropen_object((const H5R_ref_t *)&ref_buf[0], H5P_DEFAULT, H5P_DEFAULT);
+    H5Dread(dset1, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, dset_buf);
+    H5Dclose(dset1);
+    H5Rdestroy(&ref_buf[0]);
+
+    for (i = 0; i < BUF_SIZE; i++)
+        assert(dset_buf[i] == i);
+
+    return 0;
+}
+
diff --git a/examples/h5_reference.c b/examples/h5_reference_deprec.c
index 32a5f59..32a5f59 100644
--- a/examples/h5_reference.c
+++ b/examples/h5_reference_deprec.c
diff --git a/examples/run-c-ex.sh.in b/examples/run-c-ex.sh.in
index 209cdd7..a70117f 100644
--- a/examples/run-c-ex.sh.in
+++ b/examples/run-c-ex.sh.in
@@ -112,12 +112,16 @@ then
         rm h5_attribute &&\
         RunTest h5_mount &&\
         rm h5_mount &&\
-        RunTest h5_reference &&\
-        rm h5_reference &&\
+        RunTest h5_reference_deprec &&\
+        rm h5_reference_deprec &&\
+        RunTest h5_ref_extern &&\
+        rm h5_ref_extern &&\
+        RunTest h5_ref_compat &&\
+        rm h5_ref_compat &&\
         RunTest h5_drivers &&\
         rm h5_drivers &&\
-        RunTest h5_ref2reg &&\
-        rm h5_ref2reg &&\
+        RunTest h5_ref2reg_deprec &&\
+        rm h5_ref2reg_deprec &&\
         RunTest h5_extlink &&\
         rm h5_extlink &&\
         RunTest h5_elink_unix2win &&\
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index b50fa71..9bb73a9 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -446,6 +446,7 @@ set (H5O_SOURCES
     ${HDF5_SRC_DIR}/H5Ochunk.c
     ${HDF5_SRC_DIR}/H5Ocont.c
     ${HDF5_SRC_DIR}/H5Ocopy.c
+    ${HDF5_SRC_DIR}/H5Ocopy_ref.c
     ${HDF5_SRC_DIR}/H5Odbg.c
     ${HDF5_SRC_DIR}/H5Odeprec.c
     ${HDF5_SRC_DIR}/H5Odrvinfo.c
@@ -616,6 +617,7 @@ set (H5T_SOURCES
     ${HDF5_SRC_DIR}/H5Torder.c
     ${HDF5_SRC_DIR}/H5Tpad.c
     ${HDF5_SRC_DIR}/H5Tprecis.c
+    ${HDF5_SRC_DIR}/H5Tref.c
     ${HDF5_SRC_DIR}/H5Tstrpad.c
     ${HDF5_SRC_DIR}/H5Tvisit.c
     ${HDF5_SRC_DIR}/H5Tvlen.c
diff --git a/src/H5Aint.c b/src/H5Aint.c
index c1c0078..2b43a64 100644
--- a/src/H5Aint.c
+++ b/src/H5Aint.c
@@ -2270,7 +2270,7 @@ H5A__attr_copy_file(const H5A_t *attr_src, H5F_t *file_dst, hbool_t *recompute_s
 
             H5MM_memcpy(attr_dst->shared->data, buf, attr_dst->shared->data_size);
 
-            if(H5D_vlen_reclaim(tid_mem, buf_space, reclaim_buf) < 0)
+            if(H5T_reclaim(tid_mem, buf_space, reclaim_buf) < 0)
                 HGOTO_ERROR(H5E_DATASET, H5E_BADITER, NULL, "unable to reclaim variable-length data")
         }  /* end if */
         else {
@@ -2401,17 +2401,9 @@ H5A__attr_post_copy_file(const H5O_loc_t *src_oloc, const H5A_t *attr_src,
 
         /* Check for expanding references */
         if(cpy_info->expand_ref) {
-            size_t ref_count;
-            size_t dst_dt_size;         /* Destination datatype size */
-
-            /* Determine size of the destination datatype */
-            if(0 == (dst_dt_size = H5T_get_size(attr_dst->shared->dt)))
-                HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "unable to determine datatype size")
-            /* Determine # of reference elements to copy */
-            ref_count = attr_dst->shared->data_size / dst_dt_size;
-
             /* Copy objects referenced in source buffer to destination file and set destination elements */
-            if(H5O_copy_expand_ref(file_src, attr_dst->shared->data, file_dst, attr_dst->shared->data, ref_count, H5T_get_ref_type(attr_dst->shared->dt), cpy_info) < 0)
+            if(H5O_copy_expand_ref(file_src, H5I_INVALID_HID, attr_src->shared->dt,
+                attr_src->shared->data, attr_src->shared->data_size, file_dst, attr_dst->shared->data, cpy_info) < 0)
                 HGOTO_ERROR(H5E_ATTR, H5E_CANTCOPY, FAIL, "unable to copy reference attribute")
         } /* end if */
         else
diff --git a/src/H5D.c b/src/H5D.c
index 96dce3f..9d811c6 100644
--- a/src/H5D.c
+++ b/src/H5D.c
@@ -706,56 +706,6 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5Dvlen_reclaim
- *
- * Purpose: Frees the buffers allocated for storing variable-length data
- *      in memory.  Only frees the VL data in the selection defined in the
- *      dataspace.  The dataset transfer property list is required to find the
- *      correct allocation/free methods for the VL data in the buffer.
- *
- * Return:  Non-negative on success, negative on failure
- *
- * Programmer:  Quincey Koziol
- *              Thursday, June 10, 1999
- *
- *-------------------------------------------------------------------------
- */
-herr_t
-H5Dvlen_reclaim(hid_t type_id, hid_t space_id, hid_t dxpl_id, void *buf)
-{
-    H5S_t *space;               /* Dataspace for iteration */
-    herr_t ret_value;           /* Return value */
-
-    FUNC_ENTER_API(FAIL)
-    H5TRACE4("e", "iii*x", type_id, space_id, dxpl_id, buf);
-
-    /* Check args */
-    if(H5I_DATATYPE != H5I_get_type(type_id) || buf == NULL)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid argument")
-    if(NULL == (space = (H5S_t *)H5I_object_verify(space_id, H5I_DATASPACE)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid dataspace")
-    if(!(H5S_has_extent(space)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "dataspace does not have extent set")
-
-    /* Get the default dataset transfer property list if the user didn't provide one */
-    if(H5P_DEFAULT == dxpl_id)
-        dxpl_id = H5P_DATASET_XFER_DEFAULT;
-    else
-        if(TRUE != H5P_isa_class(dxpl_id, H5P_DATASET_XFER))
-            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not xfer parms")
-
-    /* Set DXPL for operation */
-    H5CX_set_dxpl(dxpl_id);
-
-    /* Call internal routine */
-    ret_value = H5D_vlen_reclaim(type_id, space, buf);
-
-done:
-    FUNC_LEAVE_API(ret_value)
-}   /* end H5Dvlen_reclaim() */
-
-
-/*-------------------------------------------------------------------------
  * Function:    H5Dvlen_get_buf_size
  *
  * Purpose: This routine checks the number of bytes required to store the VL
diff --git a/src/H5Dchunk.c b/src/H5Dchunk.c
index ed82b3b..53ca7d1 100644
--- a/src/H5Dchunk.c
+++ b/src/H5Dchunk.c
@@ -6088,23 +6088,15 @@ H5D__chunk_copy_cb(const H5D_chunk_rec_t *chunk_rec, void *_udata)
             HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, H5_ITER_ERROR, "datatype conversion failed")
 
         /* Reclaim space from variable length data */
-        if(H5D_vlen_reclaim(tid_mem, buf_space, reclaim_buf) < 0)
+        if(H5T_reclaim(tid_mem, buf_space, reclaim_buf) < 0)
             HGOTO_ERROR(H5E_DATASET, H5E_BADITER, H5_ITER_ERROR, "unable to reclaim variable-length data")
     } /* end if */
     else if(fix_ref) {
         /* Check for expanding references */
         /* (background buffer has already been zeroed out, if not expanding) */
         if(udata->cpy_info->expand_ref) {
-            size_t ref_count;
-            size_t dt_size;
-
-            /* Determine # of reference elements to copy */
-            if((dt_size = H5T_get_size(udata->dt_src)) == 0)
-                HGOTO_ERROR(H5E_DATASET, H5E_BADVALUE, FAIL, "size must not be 0")
-            ref_count = nbytes / dt_size;
-
             /* Copy the reference elements */
-            if(H5O_copy_expand_ref(udata->file_src, buf, udata->idx_info_dst->f, bkg, ref_count, H5T_get_ref_type(udata->dt_src), udata->cpy_info) < 0)
+            if(H5O_copy_expand_ref(udata->file_src, udata->tid_src, udata->dt_src, buf, nbytes, udata->idx_info_dst->f, bkg, udata->cpy_info) < 0)
                 HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, H5_ITER_ERROR, "unable to copy reference attribute")
         } /* end if */
 
diff --git a/src/H5Dcompact.c b/src/H5Dcompact.c
index 29401f8..edad3c5 100644
--- a/src/H5Dcompact.c
+++ b/src/H5Dcompact.c
@@ -551,26 +551,16 @@ H5D__compact_copy(H5F_t *f_src, H5O_storage_compact_t *_storage_src, H5F_t *f_ds
 
         H5MM_memcpy(storage_dst->buf, buf, storage_dst->size);
 
-        if(H5D_vlen_reclaim(tid_mem, buf_space, reclaim_buf) < 0)
+        if(H5T_reclaim(tid_mem, buf_space, reclaim_buf) < 0)
             HGOTO_ERROR(H5E_DATASET, H5E_BADITER, FAIL, "unable to reclaim variable-length data")
     } /* end if */
     else if(H5T_get_class(dt_src, FALSE) == H5T_REFERENCE) {
         if(f_src != f_dst) {
             /* Check for expanding references */
             if(cpy_info->expand_ref) {
-                size_t ref_count;
-                size_t src_dt_size;         /* Source datatype size */
-
-                /* Determine largest datatype size */
-                if(0 == (src_dt_size = H5T_get_size(dt_src)))
-                    HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "unable to determine datatype size")
-
-                /* Determine # of reference elements to copy */
-                ref_count = storage_src->size / src_dt_size;
-
                 /* Copy objects referenced in source buffer to destination file and set destination elements */
-                if(H5O_copy_expand_ref(f_src, storage_src->buf, f_dst,
-                        storage_dst->buf, ref_count, H5T_get_ref_type(dt_src), cpy_info) < 0)
+                if (H5O_copy_expand_ref(f_src, tid_src, dt_src, storage_src->buf,
+                    storage_src->size, f_dst, storage_dst->buf, cpy_info) < 0)
                     HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "unable to copy reference attribute")
             } /* end if */
             else
diff --git a/src/H5Dcontig.c b/src/H5Dcontig.c
index c9f9fc2..0be7364 100644
--- a/src/H5Dcontig.c
+++ b/src/H5Dcontig.c
@@ -1543,19 +1543,14 @@ H5D__contig_copy(H5F_t *f_src, const H5O_storage_contig_t *storage_src,
                 HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "datatype conversion failed")
 
             /* Reclaim space from variable length data */
-            if(H5D_vlen_reclaim(tid_mem, buf_space, reclaim_buf) < 0)
+            if(H5T_reclaim(tid_mem, buf_space, reclaim_buf) < 0)
                 HGOTO_ERROR(H5E_DATASET, H5E_BADITER, FAIL, "unable to reclaim variable-length data")
         } /* end if */
         else if(fix_ref) {
             /* Check for expanding references */
             if(cpy_info->expand_ref) {
-                size_t ref_count;
-
-                /* Determine # of reference elements to copy */
-                ref_count = src_nbytes / H5T_get_size(dt_src);
-
                 /* Copy the reference elements */
-                if(H5O_copy_expand_ref(f_src, buf, f_dst, bkg, ref_count, H5T_get_ref_type(dt_src), cpy_info) < 0)
+                if(H5O_copy_expand_ref(f_src, tid_src, dt_src, buf, buf_size, f_dst, bkg, cpy_info) < 0)
                     HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "unable to copy reference attribute")
 
                 /* After fix ref, copy the new reference elements to the buffer to write out */
diff --git a/src/H5Ddeprec.c b/src/H5Ddeprec.c
index 6380bee..f321c82 100644
--- a/src/H5Ddeprec.c
+++ b/src/H5Ddeprec.c
@@ -303,5 +303,55 @@ done:
 
     FUNC_LEAVE_API(ret_value)
 } /* end H5Dextend() */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Dvlen_reclaim
+ *
+ * Purpose: Frees the buffers allocated for storing variable-length data
+ *      in memory.  Only frees the VL data in the selection defined in the
+ *      dataspace.  The dataset transfer property list is required to find the
+ *      correct allocation/free methods for the VL data in the buffer.
+ *
+ * Return:  Non-negative on success, negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              Thursday, June 10, 1999
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Dvlen_reclaim(hid_t type_id, hid_t space_id, hid_t dxpl_id, void *buf)
+{
+    H5S_t *space;               /* Dataspace for iteration */
+    herr_t ret_value;           /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE4("e", "iii*x", type_id, space_id, dxpl_id, buf);
+
+    /* Check args */
+    if(H5I_DATATYPE != H5I_get_type(type_id) || buf == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid argument")
+    if(NULL == (space = (H5S_t *)H5I_object_verify(space_id, H5I_DATASPACE)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid dataspace")
+    if(!(H5S_has_extent(space)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "dataspace does not have extent set")
+
+    /* Get the default dataset transfer property list if the user didn't provide one */
+    if(H5P_DEFAULT == dxpl_id)
+        dxpl_id = H5P_DATASET_XFER_DEFAULT;
+    else
+        if(TRUE != H5P_isa_class(dxpl_id, H5P_DATASET_XFER))
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not xfer parms")
+
+    /* Set DXPL for operation */
+    H5CX_set_dxpl(dxpl_id);
+
+    /* Call internal routine */
+    ret_value = H5T_reclaim(type_id, space, buf);
+
+done:
+    FUNC_LEAVE_API(ret_value)
+}   /* end H5Dvlen_reclaim() */
+
 #endif /* H5_NO_DEPRECATED_SYMBOLS */
 
diff --git a/src/H5Dint.c b/src/H5Dint.c
index ada542e..772a150 100644
--- a/src/H5Dint.c
+++ b/src/H5Dint.c
@@ -547,7 +547,7 @@ H5D__init_type(H5F_t *file, const H5D_t *dset, hid_t type_id, const H5T_t *type)
     /* To use at least v18 format versions or not */
     use_at_least_v18 = (H5F_LOW_BOUND(file) >= H5F_LIBVER_V18);
 
-    /* Copy the datatype if it's a custom datatype or if it'll change when it's location is changed */
+    /* Copy the datatype if it's a custom datatype or if it'll change when its location is changed */
     if(!immutable || relocatable || use_at_least_v18) {
         /* Copy datatype for dataset */
         if((dset->shared->type = H5T_copy(type, H5T_COPY_ALL)) == NULL)
@@ -2542,50 +2542,6 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function: H5D_vlen_reclaim
- *
- * Purpose:  Frees the buffers allocated for storing variable-length data
- *           in memory.  Only frees the VL data in the selection defined in the
- *           dataspace.
- *
- * Return:   Non-negative on success, negative on failure
- *-------------------------------------------------------------------------
- */
-herr_t
-H5D_vlen_reclaim(hid_t type_id, H5S_t *space, void *buf)
-{
-    H5T_t *type;                /* Datatype */
-    H5S_sel_iter_op_t dset_op;  /* Operator for iteration */
-    H5T_vlen_alloc_info_t vl_alloc_info;   /* VL allocation info */
-    herr_t ret_value = FAIL;    /* Return value */
-
-    FUNC_ENTER_NOAPI(FAIL)
-
-    /* Check args */
-    HDassert(H5I_DATATYPE == H5I_get_type(type_id));
-    HDassert(space);
-    HDassert(buf);
-
-    if(NULL == (type = (H5T_t *)H5I_object_verify(type_id, H5I_DATATYPE)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an valid base datatype")
-
-    /* Get the allocation info */
-    if(H5CX_get_vlen_alloc_info(&vl_alloc_info) < 0)
-        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTGET, FAIL, "unable to retrieve VL allocation info")
-
-    /* Call H5S_select_iterate with args, etc. */
-    dset_op.op_type = H5S_SEL_ITER_OP_APP;
-    dset_op.u.app_op.op = H5T_vlen_reclaim;
-    dset_op.u.app_op.type_id = type_id;
-
-    ret_value = H5S_select_iterate(buf, type, space, &dset_op, &vl_alloc_info);
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-}   /* end H5D_vlen_reclaim() */
-
-
-/*-------------------------------------------------------------------------
  * Function: H5D__vlen_get_buf_size_alloc
  *
  * Purpose:  This routine makes certain there is enough space in the temporary
diff --git a/src/H5Dio.c b/src/H5Dio.c
index 5160de8..79a856a 100644
--- a/src/H5Dio.c
+++ b/src/H5Dio.c
@@ -32,11 +32,6 @@
 
 #include "H5VLnative_private.h" /* Native VOL connector                     */
 
-#ifdef H5_HAVE_PARALLEL
-/* Remove this if H5R_DATASET_REGION is no longer used in this file */
-#include "H5Rpublic.h"
-#endif /*H5_HAVE_PARALLEL*/
-
 
 /****************/
 /* Local Macros */
diff --git a/src/H5Dprivate.h b/src/H5Dprivate.h
index 511e380..9a5277f 100644
--- a/src/H5Dprivate.h
+++ b/src/H5Dprivate.h
@@ -170,9 +170,6 @@ H5_DLL herr_t H5D_flush_all(H5F_t *f);
 H5_DLL hid_t H5D_get_create_plist(const H5D_t *dset);
 H5_DLL hid_t H5D_get_access_plist(const H5D_t *dset);
 
-/* Functions that operate on vlen data */
-H5_DLL herr_t H5D_vlen_reclaim(hid_t type_id, H5S_t *space, void *buf);
-
 /* Functions that operate on chunked storage */
 H5_DLL herr_t H5D_chunk_idx_reset(H5O_storage_chunk_t *storage, hbool_t reset_addr);
 
diff --git a/src/H5Dpublic.h b/src/H5Dpublic.h
index 7234d16..281da81 100644
--- a/src/H5Dpublic.h
+++ b/src/H5Dpublic.h
@@ -156,7 +156,6 @@ H5_DLL herr_t H5Dread_chunk(hid_t dset_id, hid_t dxpl_id,
             const hsize_t *offset, uint32_t *filters, void *buf);
 H5_DLL herr_t H5Diterate(void *buf, hid_t type_id, hid_t space_id,
             H5D_operator_t op, void *operator_data);
-H5_DLL herr_t H5Dvlen_reclaim(hid_t type_id, hid_t space_id, hid_t plist_id, void *buf);
 H5_DLL herr_t H5Dvlen_get_buf_size(hid_t dataset_id, hid_t type_id, hid_t space_id, hsize_t *size);
 H5_DLL herr_t H5Dfill(const void *fill, hid_t fill_type, void *buf,
         hid_t buf_type, hid_t space);
@@ -203,6 +202,7 @@ H5_DLL hid_t H5Dcreate1(hid_t file_id, const char *name, hid_t type_id,
     hid_t space_id, hid_t dcpl_id);
 H5_DLL hid_t H5Dopen1(hid_t file_id, const char *name);
 H5_DLL herr_t H5Dextend(hid_t dset_id, const hsize_t size[]);
+H5_DLL herr_t H5Dvlen_reclaim(hid_t type_id, hid_t space_id, hid_t plist_id, void *buf);
 
 #endif /* H5_NO_DEPRECATED_SYMBOLS */
 
diff --git a/src/H5Ocopy.c b/src/H5Ocopy.c
index 9578f95..6e0db25 100644
--- a/src/H5Ocopy.c
+++ b/src/H5Ocopy.c
@@ -85,8 +85,6 @@ static herr_t H5O__copy_header(const H5O_loc_t *oloc_src, H5O_loc_t *oloc_dst /*
     hid_t ocpypl_id, hid_t lcpl_id);
 static herr_t H5O__copy_obj(H5G_loc_t *src_loc, H5G_loc_t *dst_loc,
     const char *dst_name, hid_t ocpypl_id, hid_t lcpl_id);
-static herr_t H5O__copy_obj_by_ref(H5O_loc_t *src_oloc, H5O_loc_t *dst_oloc,
-    H5G_loc_t *dst_root_loc, H5O_copy_t *cpy_info);
 static herr_t H5O__copy_free_comm_dt_cb(void *item, void *key, void *op_data);
 static int H5O__copy_comm_dt_cmp(const void *dt1, const void *dt2);
 static herr_t H5O__copy_search_comm_dt_cb(hid_t group, const char *name,
@@ -110,7 +108,6 @@ H5FL_DEFINE(H5O_copy_search_comm_dt_key_t);
 /* Declare a free list to manage haddr_t variables */
 H5FL_DEFINE(haddr_t);
 
-
 /*****************************/
 /* Library Private Variables */
 /*****************************/
@@ -1235,201 +1232,6 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5O__copy_obj_by_ref
- *
- * Purpose:     Copy the object pointed by _src_ref.
- *
- * Return:      Non-negative on success/Negative on failure
- *
- * Programmer:  Peter Cao
- *              Aug 7 2006
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5O__copy_obj_by_ref(H5O_loc_t *src_oloc, H5O_loc_t *dst_oloc,
-    H5G_loc_t *dst_root_loc, H5O_copy_t *cpy_info)
-{
-    herr_t  ret_value = SUCCEED;
-
-    FUNC_ENTER_STATIC
-
-    HDassert(src_oloc);
-    HDassert(dst_oloc);
-
-    /* Perform the copy, or look up existing copy */
-    if((ret_value = H5O_copy_header_map(src_oloc, dst_oloc, cpy_info, FALSE, NULL, NULL)) < 0)
-        HGOTO_ERROR(H5E_OHDR, H5E_CANTCOPY, FAIL, "unable to copy object")
-
-    /* Check if a new valid object is copied to the destination */
-    if(H5F_addr_defined(dst_oloc->addr) && (ret_value > SUCCEED)) {
-        char    tmp_obj_name[80];
-        H5G_name_t      new_path;
-        H5O_loc_t       new_oloc;
-        H5G_loc_t       new_loc;
-
-        /* Set up group location for new object */
-        new_loc.oloc = &new_oloc;
-        new_loc.path = &new_path;
-        H5G_loc_reset(&new_loc);
-        new_oloc.file = dst_oloc->file;
-        new_oloc.addr = dst_oloc->addr;
-
-        /* Pick a default name for the new object */
-        HDsnprintf(tmp_obj_name, sizeof(tmp_obj_name), "~obj_pointed_by_%llu", (unsigned long long)dst_oloc->addr);
-
-        /* Create a link to the newly copied object */
-        /* Note: since H5O_copy_header_map actually copied the target object, it
-         * must exist either in cache or on disk, therefore it is is safe to not
-         * pass the obj_type and udata fields returned by H5O_copy_header_map.
-         * This could be changed in the future to slightly improve performance
-         * --NAF */
-        if(H5L_link(dst_root_loc, tmp_obj_name, &new_loc, cpy_info->lcpl_id) < 0)
-            HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "unable to insert link")
-
-        H5G_loc_free(&new_loc);
-    } /* if (H5F_addr_defined(dst_oloc.addr)) */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5O__copy_obj_by_ref() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5O_copy_expand_ref
- *
- * Purpose:	Copy the object pointed by _src_ref.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:  Peter Cao
- *		Aug 7 2006
- *
- *-------------------------------------------------------------------------
- */
-herr_t
-H5O_copy_expand_ref(H5F_t *file_src, void *_src_ref, H5F_t *file_dst,
-    void *_dst_ref, size_t ref_count, H5R_type_t ref_type, H5O_copy_t *cpy_info)
-{
-    H5O_loc_t 	dst_oloc;         	/* Copied object object location */
-    H5O_loc_t	src_oloc;          	/* Temporary object location for source object */
-    H5G_loc_t   dst_root_loc;           /* The location of root group of the destination file */
-    const uint8_t *q;                   /* Pointer to source OID to store */
-    uint8_t     *p;                     /* Pointer to destination OID to store */
-    size_t      i;                      /* Local index variable */
-    herr_t	ret_value = SUCCEED;
-
-    FUNC_ENTER_NOAPI(FAIL)
-
-    /* Sanity checks */
-    HDassert(file_src);
-    HDassert(_src_ref);
-    HDassert(file_dst);
-    HDassert(_dst_ref);
-    HDassert(ref_count);
-    HDassert(cpy_info);
-
-    /* Initialize object locations */
-    H5O_loc_reset(&src_oloc);
-    H5O_loc_reset(&dst_oloc);
-    src_oloc.file = file_src;
-    dst_oloc.file = file_dst;
-
-    /* Set up the root group in the destination file */
-    if(NULL == (dst_root_loc.oloc = H5G_oloc(H5G_rootof(file_dst))))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "unable to get object location for root group")
-    if(NULL == (dst_root_loc.path = H5G_nameof(H5G_rootof(file_dst))))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "unable to get path for root group")
-
-    /* Copy object references */
-    if(H5R_OBJECT == ref_type) {
-        hobj_ref_t *src_ref = (hobj_ref_t *)_src_ref;
-        hobj_ref_t *dst_ref = (hobj_ref_t *)_dst_ref;
-
-        /* Making equivalent references in the destination file */
-        for(i = 0; i < ref_count; i++) {
-            /* Set up for the object copy for the reference */
-            q = (uint8_t *)(&src_ref[i]);
-            H5F_addr_decode(src_oloc.file, (const uint8_t **)&q, &(src_oloc.addr));
-            dst_oloc.addr = HADDR_UNDEF;
-
-            /* Attempt to copy object from source to destination file */
-            if(src_oloc.addr != (haddr_t)0) {
-                if(H5O__copy_obj_by_ref(&src_oloc, &dst_oloc, &dst_root_loc, cpy_info) < 0)
-                    HGOTO_ERROR(H5E_OHDR, H5E_CANTCOPY, FAIL, "unable to copy object")
-            } /* end if */
-            else
-                /* Set parameters so the reference is written as all 0's */
-                HDmemset(&dst_oloc.addr, 0, sizeof(dst_oloc.addr));
-
-            /* Set the object reference info for the destination file */
-            p = (uint8_t *)(&dst_ref[i]);
-            H5F_addr_encode(dst_oloc.file, &p, dst_oloc.addr);
-	} /* end for */
-    }  /* end if */
-    /* Copy region references */
-    else if(H5R_DATASET_REGION == ref_type) {
-        hdset_reg_ref_t *src_ref = (hdset_reg_ref_t *)_src_ref;
-        hdset_reg_ref_t *dst_ref = (hdset_reg_ref_t *)_dst_ref;
-        uint8_t *buf = NULL;    /* Buffer to store serialized selection in */
-        H5HG_t hobjid;          /* Heap object ID */
-        size_t buf_size;        /* Length of object in heap */
-
-        /* Making equivalent references in the destination file */
-        for(i = 0; i < ref_count; i++) {
-            /* Get the heap ID for the dataset region */
-            q = (const uint8_t *)(&src_ref[i]);
-            H5F_addr_decode(src_oloc.file, (const uint8_t **)&q, &(hobjid.addr));
-            UINT32DECODE(q, hobjid.idx);
-
-            if(hobjid.addr != (haddr_t)0) {
-                /* Get the dataset region from the heap (allocate inside routine) */
-                if((buf = (uint8_t *)H5HG_read(src_oloc.file, &hobjid, NULL, &buf_size)) == NULL)
-                    HGOTO_ERROR(H5E_REFERENCE, H5E_READERROR, FAIL, "Unable to read dataset region information")
-
-                /* Get the object oid for the dataset */
-                q = (const uint8_t *)buf;
-                H5F_addr_decode(src_oloc.file, (const uint8_t **)&q, &(src_oloc.addr));
-                dst_oloc.addr = HADDR_UNDEF;
-
-                /* copy the object pointed by the ref to the destination */
-                if(H5O__copy_obj_by_ref(&src_oloc, &dst_oloc, &dst_root_loc, cpy_info) < 0) {
-                    H5MM_xfree(buf);
-                    HGOTO_ERROR(H5E_OHDR, H5E_CANTCOPY, FAIL, "unable to copy object")
-                } /* end if */
-
-                /* Serialize object ID */
-                p = (uint8_t *)buf;
-                H5F_addr_encode(dst_oloc.file, &p, dst_oloc.addr);
-
-                /* Save the serialized buffer to the destination */
-                if(H5HG_insert(dst_oloc.file, buf_size, buf, &hobjid) < 0) {
-                    H5MM_xfree(buf);
-                    HGOTO_ERROR(H5E_OHDR, H5E_CANTCOPY, FAIL, "Unable to write dataset region information")
-                } /* end if */
-            } /* end if */
-            else
-                /* Set parameters so the reference is written as all 0's */
-                HDmemset(&hobjid, 0, sizeof(hobjid));
-
-            /* Set the dataset region reference info for the destination file */
-            p = (uint8_t *)(&dst_ref[i]);
-            H5F_addr_encode(dst_oloc.file, &p, hobjid.addr);
-            UINT32ENCODE(p, hobjid.idx);
-
-            /* Free the buffer allocated in H5HG_read() */
-            H5MM_xfree(buf);
-        } /* end for */
-    } /* end if */
-    else
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference type")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5O_copy_expand_ref() */
-
-
-/*-------------------------------------------------------------------------
  * Function:    H5O__copy_free_comm_dt_cb
  *
  * Purpose:     Frees the merge committed dt skip list key and object.
diff --git a/src/H5Ocopy_ref.c b/src/H5Ocopy_ref.c
new file mode 100644
index 0000000..e8212d6bb
--- /dev/null
+++ b/src/H5Ocopy_ref.c
@@ -0,0 +1,485 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the COPYING file, which can be found at the root of the source code       *
+ * distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.  *
+ * If you do not have access to either file, you may request a copy from     *
+ * help@hdfgroup.org.                                                        *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*-------------------------------------------------------------------------
+ *
+ * Created:     H5Ocopy_ref.c
+ *
+ * Purpose:     Object with references copying routines.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+/****************/
+/* Module Setup */
+/****************/
+
+#include "H5Omodule.h"          /* This source code file is part of the H5O module */
+#define H5F_FRIEND              /* Suppress error about including H5Fpkg   */
+#define H5R_FRIEND              /* Suppress error about including H5Rpkg   */
+
+
+/***********/
+/* Headers */
+/***********/
+#include "H5private.h"          /* Generic Functions                        */
+#include "H5Fpkg.h"             /* File                                     */
+#include "H5Iprivate.h"         /* IDs                                      */
+#include "H5Lprivate.h"         /* Links                                    */
+#include "H5MMprivate.h"        /* Memory management                        */
+#include "H5Opkg.h"             /* Object headers                           */
+#include "H5Rpkg.h"             /* References                               */
+
+
+/****************/
+/* Local Macros */
+/****************/
+
+
+/******************/
+/* Local Typedefs */
+/******************/
+
+/********************/
+/* Package Typedefs */
+/********************/
+
+
+/********************/
+/* Local Prototypes */
+/********************/
+
+static herr_t H5O__copy_obj_by_ref(H5O_loc_t *src_oloc, H5O_loc_t *dst_oloc,
+    H5G_loc_t *dst_root_loc, H5O_copy_t *cpy_info);
+static herr_t H5O__copy_expand_ref_object1(H5O_loc_t *src_oloc,
+    const void *buf_src, H5O_loc_t *dst_oloc, H5G_loc_t *dst_root_loc,
+    void *buf_dst, size_t ref_count, H5O_copy_t *cpy_info);
+static herr_t H5O__copy_expand_ref_region1(H5O_loc_t *src_oloc,
+    const void *buf_src, H5O_loc_t *dst_oloc, H5G_loc_t *dst_root_loc,
+    void *buf_dst, size_t ref_count, H5O_copy_t *cpy_info);
+static herr_t H5O__copy_expand_ref_object2(H5O_loc_t *src_oloc, hid_t tid_src,
+    H5T_t *dt_src, const void *buf_src, size_t nbytes_src, H5O_loc_t *dst_oloc,
+    H5G_loc_t *dst_root_loc, void *buf_dst, size_t ref_count,
+    H5O_copy_t *cpy_info);
+
+/*********************/
+/* Package Variables */
+/*********************/
+
+/* Declare extern the free list to manage blocks of type conversion data */
+H5FL_BLK_EXTERN(type_conv);
+
+/*****************************/
+/* Library Private Variables */
+/*****************************/
+
+
+/*******************/
+/* Local Variables */
+/*******************/
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5O__copy_obj_by_ref
+ *
+ * Purpose:     Copy the object pointed to by src_oloc.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O__copy_obj_by_ref(H5O_loc_t *src_oloc, H5O_loc_t *dst_oloc,
+    H5G_loc_t *dst_root_loc, H5O_copy_t *cpy_info)
+{
+    herr_t  ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(src_oloc);
+    HDassert(dst_oloc);
+
+    /* Perform the copy, or look up existing copy */
+    if((ret_value = H5O_copy_header_map(src_oloc, dst_oloc, cpy_info, FALSE, NULL, NULL)) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTCOPY, FAIL, "unable to copy object")
+
+    /* Check if a new valid object is copied to the destination */
+    if(H5F_addr_defined(dst_oloc->addr) && (ret_value > SUCCEED)) {
+        char    tmp_obj_name[80];
+        H5G_name_t      new_path;
+        H5O_loc_t       new_oloc;
+        H5G_loc_t       new_loc;
+
+        /* Set up group location for new object */
+        new_loc.oloc = &new_oloc;
+        new_loc.path = &new_path;
+        H5G_loc_reset(&new_loc);
+        new_oloc.file = dst_oloc->file;
+        new_oloc.addr = dst_oloc->addr;
+
+        /* Pick a default name for the new object */
+        HDsnprintf(tmp_obj_name, sizeof(tmp_obj_name), "~obj_pointed_by_%llu", (unsigned long long)dst_oloc->addr);
+
+        /* Create a link to the newly copied object */
+        /* Note: since H5O_copy_header_map actually copied the target object, it
+         * must exist either in cache or on disk, therefore it is is safe to not
+         * pass the obj_type and udata fields returned by H5O_copy_header_map.
+         * This could be changed in the future to slightly improve performance
+         * --NAF */
+        if(H5L_link(dst_root_loc, tmp_obj_name, &new_loc, cpy_info->lcpl_id) < 0)
+            HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "unable to insert link")
+
+        H5G_loc_free(&new_loc);
+    } /* if (H5F_addr_defined(dst_oloc.addr)) */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O__copy_obj_by_ref() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5O__copy_expand_ref_object1
+ *
+ * Purpose: Copy the object pointed by a deprecated object reference.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O__copy_expand_ref_object1(H5O_loc_t *src_oloc, const void *buf_src,
+    H5O_loc_t *dst_oloc, H5G_loc_t *dst_root_loc, void *buf_dst,
+    size_t ref_count, H5O_copy_t *cpy_info)
+{
+    const hobj_ref_t *src_ref = (const hobj_ref_t *)buf_src;
+    hobj_ref_t *dst_ref       = (hobj_ref_t *)buf_dst;
+    const unsigned char zeros[H5R_OBJ_REF_BUF_SIZE] = { 0 };
+    size_t buf_size = H5R_OBJ_REF_BUF_SIZE;
+    size_t i; /* Local index variable */
+    herr_t  ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    /* Making equivalent references in the destination file */
+    for(i = 0; i < ref_count; i++) {
+        const unsigned char *src_buf = (const unsigned char *)&src_ref[i];
+        unsigned char *dst_buf = (unsigned char *)&dst_ref[i];
+
+        /* If data is not initialized, copy zeros and skip */
+        if(0 == HDmemcmp(src_buf, zeros, buf_size)) {
+            HDmemset(dst_buf, 0, buf_size);
+            continue;
+        }
+
+        /* Set up for the object copy for the reference */
+        if(H5R__decode_addr_obj_compat(src_buf, &buf_size, &src_oloc->addr) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTDECODE, FAIL, "unable to decode src object address")
+        if(!H5F_addr_defined(src_oloc->addr) || src_oloc->addr == 0)
+            HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "undefined reference pointer")
+        dst_oloc->addr = HADDR_UNDEF;
+
+        /* Attempt to copy object from source to destination file */
+        if(H5O__copy_obj_by_ref(src_oloc, dst_oloc, dst_root_loc, cpy_info) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTCOPY, FAIL, "unable to copy object")
+
+        /* Set the object reference info for the destination file */
+        if(H5R__encode_addr_obj_compat(dst_oloc->addr, dst_buf, &buf_size) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTDECODE, FAIL, "unable to encode dst object address")
+    } /* end for */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O__copy_expand_ref_object1() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5O__copy_expand_ref_region1
+ *
+ * Purpose: Copy the object pointed by a deprecated region reference.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O__copy_expand_ref_region1(H5O_loc_t *src_oloc, const void *buf_src,
+    H5O_loc_t *dst_oloc, H5G_loc_t *dst_root_loc, void *buf_dst,
+    size_t ref_count, H5O_copy_t *cpy_info)
+{
+    const hdset_reg_ref_t *src_ref = (const hdset_reg_ref_t *)buf_src;
+    hdset_reg_ref_t *dst_ref       = (hdset_reg_ref_t *)buf_dst;
+    const unsigned char zeros[H5R_DSET_REG_REF_BUF_SIZE] = { 0 };
+    size_t buf_size = H5R_DSET_REG_REF_BUF_SIZE;
+    size_t i; /* Local index variable */
+    herr_t  ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    /* Making equivalent references in the destination file */
+    for(i = 0; i < ref_count; i++) {
+        const unsigned char *src_buf = (const unsigned char *)&src_ref[i];
+        unsigned char *dst_buf = (unsigned char *)&dst_ref[i];
+        unsigned char *data = NULL;
+        size_t data_size;
+        const uint8_t *p;
+        uint8_t *q;
+
+        /* If data is not initialized, copy zeros and skip */
+        if(0 == HDmemcmp(src_buf, zeros, buf_size)) {
+            HDmemset(dst_buf, 0, buf_size);
+            continue;
+        }
+
+        /* Read from heap */
+        if(H5R__decode_heap(src_oloc->file, src_buf, &buf_size, &data, &data_size) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTDECODE, FAIL, "unable to decode dataset region information")
+
+        /* Get object address */
+        p = (const uint8_t *)data;
+        H5F_addr_decode(src_oloc->file, &p, &src_oloc->addr);
+        if(!H5F_addr_defined(src_oloc->addr) || src_oloc->addr == 0) {
+            H5MM_free(data);
+            HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "undefined reference pointer")
+        }
+        dst_oloc->addr = HADDR_UNDEF;
+
+        /* Attempt to copy object from source to destination file */
+        if(H5O__copy_obj_by_ref(src_oloc, dst_oloc, dst_root_loc, cpy_info) < 0) {
+            H5MM_free(data);
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTCOPY, FAIL, "unable to copy object")
+        } /* end if */
+
+        /* Serialize object addr */
+        q = (uint8_t *)data;
+        H5F_addr_encode(dst_oloc->file, &q, dst_oloc->addr);
+
+        /* Write to heap */
+        if(H5R__encode_heap(dst_oloc->file, dst_buf, &buf_size, data, (size_t)data_size) < 0) {
+            H5MM_free(data);
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTENCODE, FAIL, "unable to encode dataset region information")
+        }
+
+        /* Free the buffer allocated in H5R__decode_heap() */
+        H5MM_free(data);
+    } /* end for */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O__copy_expand_ref_region1() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5O__copy_expand_ref_object2
+ *
+ * Purpose: Copy the object pointed by a reference (object, region, attribute).
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O__copy_expand_ref_object2(H5O_loc_t *src_oloc, hid_t tid_src, H5T_t *dt_src,
+    const void *buf_src, size_t nbytes_src, H5O_loc_t *dst_oloc,
+    H5G_loc_t *dst_root_loc, void *buf_dst, size_t ref_count,
+    H5O_copy_t *cpy_info)
+{
+    H5T_t       *dt_mem = NULL;             /* Memory datatype */
+    H5T_t       *dt_dst = NULL;             /* Destination datatype */
+    hid_t       tid_mem = H5I_INVALID_HID;  /* Datatype ID for memory datatype */
+    hid_t       tid_dst = H5I_INVALID_HID;  /* Datatype ID for memory datatype */
+    H5T_path_t  *tpath_src_mem = NULL,
+                *tpath_mem_dst = NULL;      /* Datatype conversion paths */
+    size_t i;                               /* Local index variable */
+    hbool_t reg_tid_src = (tid_src == H5I_INVALID_HID);
+    hid_t dst_loc_id = H5I_INVALID_HID;
+    void *conv_buf = NULL;                  /* Buffer for converting data */
+    size_t conv_buf_size = 0;               /* Buffer size */
+    void *reclaim_buf = NULL;               /* Buffer for reclaiming data */
+    H5S_t *buf_space = NULL;                /* Dataspace describing buffer */
+    hsize_t buf_dim[1] = {ref_count};       /* Dimension for buffer */
+    herr_t  ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    /* Create datatype ID for src datatype. */
+    if((tid_src == H5I_INVALID_HID) && (tid_src = H5I_register(H5I_DATATYPE, dt_src, FALSE)) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTREGISTER, FAIL, "unable to register source file datatype")
+
+    /* create a memory copy of the reference datatype */
+    if(NULL == (dt_mem = H5T_copy(dt_src, H5T_COPY_TRANSIENT)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "unable to copy")
+    if((tid_mem = H5I_register(H5I_DATATYPE, dt_mem, FALSE)) < 0) {
+        (void)H5T_close_real(dt_mem);
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTREGISTER, FAIL, "unable to register memory datatype")
+    } /* end if */
+
+    /* create reference datatype at the destinaton file */
+    if(NULL == (dt_dst = H5T_copy(dt_src, H5T_COPY_TRANSIENT)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "unable to copy")
+    if(H5T_set_loc(dt_dst, dst_oloc->file, H5T_LOC_DISK) < 0) {
+        (void)H5T_close_real(dt_dst);
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "cannot mark datatype on disk")
+    } /* end if */
+    if((tid_dst = H5I_register(H5I_DATATYPE, dt_dst, FALSE)) < 0) {
+        (void)H5T_close_real(dt_dst);
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTREGISTER, FAIL, "unable to register destination file datatype")
+    } /* end if */
+
+    /* Set up the conversion functions */
+    if(NULL == (tpath_src_mem = H5T_path_find(dt_src, dt_mem)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "unable to convert between src and mem datatypes")
+    if(NULL == (tpath_mem_dst = H5T_path_find(dt_mem, dt_dst)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "unable to convert between mem and dst datatypes")
+
+    /* Use extra conversion buffer (TODO we should avoid using an extra buffer once the H5Ocopy code has been reworked) */
+    conv_buf_size = MAX(H5T_get_size(dt_src), H5T_get_size(dt_mem)) * ref_count;
+    if(NULL == (conv_buf = H5FL_BLK_MALLOC(type_conv, conv_buf_size)))
+        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for copy buffer")
+    H5MM_memcpy(conv_buf, buf_src, nbytes_src);
+
+    /* Convert from source file to memory */
+    if(H5T_convert(tpath_src_mem, tid_src, tid_mem, ref_count, (size_t)0, (size_t)0, conv_buf, NULL) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTCONVERT, FAIL, "datatype conversion failed")
+
+    /* Retrieve loc ID */
+    if((dst_loc_id = H5F__get_file_id(dst_oloc->file, FALSE)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file or file object")
+
+    /* Making equivalent references in the destination file */
+    for(i = 0; i < ref_count; i++) {
+        H5R_ref_t *ref_ptr  = (H5R_ref_t *)conv_buf;
+        H5R_ref_priv_t *ref = (H5R_ref_priv_t *)&ref_ptr[i];
+        size_t token_size = sizeof(src_oloc->addr);
+
+        /* Get src object address */
+        if(H5R__get_obj_token(ref, (H5VL_token_t *)&src_oloc->addr, &token_size) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "unable to get object token")
+
+        /* Attempt to copy object from source to destination file */
+        if(H5O__copy_obj_by_ref(src_oloc, dst_oloc, dst_root_loc, cpy_info) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTCOPY, FAIL, "unable to copy object")
+
+        /* Set dst object address */
+        if(H5R__set_obj_token(ref, (const H5VL_token_t *)&dst_oloc->addr, token_size) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTSET, FAIL, "unable to set object token")
+        if(H5R__set_loc_id(ref, dst_loc_id, TRUE) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTSET, FAIL, "unable to set destination loc id")
+    } /* end for */
+
+    /* Copy into another buffer, to reclaim memory later */
+    if(NULL == (reclaim_buf = H5FL_BLK_MALLOC(type_conv, conv_buf_size)))
+        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for copy buffer")
+    H5MM_memcpy(reclaim_buf, conv_buf, conv_buf_size);
+    if(NULL == (buf_space = H5S_create_simple((unsigned)1, buf_dim, NULL)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTCREATE, FAIL, "can't create simple dataspace")
+
+    /* Convert from memory to destination file */
+    if(H5T_convert(tpath_mem_dst, tid_mem, tid_dst, ref_count, (size_t)0, (size_t)0, conv_buf, NULL) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTCONVERT, FAIL, "datatype conversion failed")
+    H5MM_memcpy(buf_dst, conv_buf, nbytes_src);
+
+    /* Reclaim space from reference data */
+    if(H5T_reclaim(tid_mem, buf_space, reclaim_buf) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_BADITER, FAIL, "unable to reclaim reference data")
+
+done:
+    if(buf_space && (H5S_close(buf_space) < 0))
+        HDONE_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "Can't close dataspace")
+    /* Don't decrement ID, we want to keep underlying datatype */
+    if(reg_tid_src && (tid_src > 0) && (NULL == H5I_remove(tid_src)))
+        HDONE_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "Can't decrement temporary datatype ID")
+    if((tid_mem > 0) && H5I_dec_ref(tid_mem) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "Can't decrement temporary datatype ID")
+    if((tid_dst > 0) && H5I_dec_ref(tid_dst) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "Can't decrement temporary datatype ID")
+    if(reclaim_buf)
+        reclaim_buf = H5FL_BLK_FREE(type_conv, reclaim_buf);
+    if(conv_buf)
+        conv_buf = H5FL_BLK_FREE(type_conv, conv_buf);
+    if((dst_loc_id != H5I_INVALID_HID) && (H5I_dec_ref(dst_loc_id) < 0))
+        HDONE_ERROR(H5E_OHDR, H5E_CANTDEC, FAIL, "unable to decrement refcount on location id")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O__copy_expand_ref_object2() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_copy_expand_ref
+ *
+ * Purpose:	Copy the object pointed by a reference.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_copy_expand_ref(H5F_t *file_src, hid_t tid_src, H5T_t *dt_src,
+    void *buf_src, size_t nbytes_src, H5F_t *file_dst, void *buf_dst,
+    H5O_copy_t *cpy_info)
+{
+    H5O_loc_t dst_oloc;           /* Copied object object location */
+    H5O_loc_t src_oloc;           /* Temporary object location for source object */
+    H5G_loc_t dst_root_loc;       /* The location of root group of the destination file */
+    size_t ref_count;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Sanity checks */
+    HDassert(file_src);
+    HDassert(buf_src);
+    HDassert(file_dst);
+    HDassert(buf_dst);
+    HDassert(nbytes_src);
+    HDassert(cpy_info);
+
+    /* Initialize object locations */
+    H5O_loc_reset(&src_oloc);
+    H5O_loc_reset(&dst_oloc);
+    src_oloc.file = file_src;
+    dst_oloc.file = file_dst;
+
+    /* Set up the root group in the destination file */
+    if(NULL == (dst_root_loc.oloc = H5G_oloc(H5G_rootof(file_dst))))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "unable to get object location for root group")
+    if(NULL == (dst_root_loc.path = H5G_nameof(H5G_rootof(file_dst))))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "unable to get path for root group")
+
+    /* Determine # of reference elements to copy */
+    ref_count = nbytes_src / H5T_get_size(dt_src);
+
+    /* Copy object references */
+    switch(H5T_get_ref_type(dt_src)) {
+        case H5R_OBJECT1:
+            if(H5O__copy_expand_ref_object1(&src_oloc, buf_src, &dst_oloc, &dst_root_loc, buf_dst, ref_count, cpy_info) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "unable to expand H5R_OBJECT1 reference")
+            break;
+        case H5R_DATASET_REGION1:
+            if(H5O__copy_expand_ref_region1(&src_oloc, buf_src, &dst_oloc, &dst_root_loc, buf_dst, ref_count, cpy_info) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "unable to expand H5R_DATASET_REGION1 reference")
+            break;
+        case H5R_DATASET_REGION2:
+        case H5R_ATTR:
+        case H5R_OBJECT2:
+            if(H5O__copy_expand_ref_object2(&src_oloc, tid_src, dt_src, buf_src, nbytes_src, &dst_oloc, &dst_root_loc, buf_dst, ref_count, cpy_info) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "unable to expand reference")
+            break;
+        case H5R_BADTYPE:
+        case H5R_MAXTYPE:
+        default:
+            HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference type")
+        break;
+    } /* end switch */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_copy_expand_ref() */
diff --git a/src/H5Odtype.c b/src/H5Odtype.c
index 0523e7c..805df2b 100644
--- a/src/H5Odtype.c
+++ b/src/H5Odtype.c
@@ -145,7 +145,7 @@ H5O_dtype_decode_helper(unsigned *ioflags/*in,out*/, const uint8_t **pp, H5T_t *
     /* Version, class & flags */
     UINT32DECODE(*pp, flags);
     version = (flags>>4) & 0x0f;
-    if(version < H5O_DTYPE_VERSION_1 || version > H5O_DTYPE_VERSION_3)
+    if(version < H5O_DTYPE_VERSION_1 || version > H5O_DTYPE_VERSION_LATEST)
         HGOTO_ERROR(H5E_DATATYPE, H5E_CANTLOAD, FAIL, "bad version number for datatype message")
     dt->shared->version = version;
     dt->shared->type = (H5T_class_t)(flags & 0x0f);
@@ -438,16 +438,28 @@ H5O_dtype_decode_helper(unsigned *ioflags/*in,out*/, const uint8_t **pp, H5T_t *
 
             /* Set reference type */
             dt->shared->u.atomic.u.r.rtype = (H5R_type_t)(flags & 0x0f);
-
-            /* Set extra information for object references, so the hobj_ref_t gets swizzled correctly */
-            if(dt->shared->u.atomic.u.r.rtype == H5R_OBJECT) {
-                /* Mark location this type as undefined for now.  The caller function should
-                 * decide the location. */
-                dt->shared->u.atomic.u.r.loc = H5T_LOC_BADLOC;
-
-                /* This type needs conversion */
-                dt->shared->force_conv = TRUE;
-            } /* end if */
+            if(dt->shared->u.atomic.u.r.rtype <= H5R_BADTYPE
+                || dt->shared->u.atomic.u.r.rtype >= H5R_MAXTYPE)
+                HGOTO_ERROR(H5E_DATATYPE, H5E_CANTDECODE, FAIL, "invalid reference type");
+
+            /* Set generic flag */
+            if(dt->shared->u.atomic.u.r.rtype == H5R_OBJECT2
+                || dt->shared->u.atomic.u.r.rtype == H5R_DATASET_REGION2
+                || dt->shared->u.atomic.u.r.rtype == H5R_ATTR) {
+                dt->shared->u.atomic.u.r.opaque = TRUE;
+                dt->shared->u.atomic.u.r.version = (unsigned)((flags >> 4) & 0x0f);
+                if(dt->shared->u.atomic.u.r.version != H5R_ENCODE_VERSION)
+                    HGOTO_ERROR(H5E_DATATYPE, H5E_CANTDECODE, FAIL, "reference version does not match");
+            } else
+                dt->shared->u.atomic.u.r.opaque = FALSE;
+
+            /* This type needs conversion */
+            dt->shared->force_conv = TRUE;
+
+            /* Mark location of this type as undefined for now.  The caller
+             * function should decide the location. */
+            if(H5T_set_loc(dt, NULL, H5T_LOC_BADLOC) < 0)
+                HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "invalid datatype location")
             break;
 
         case H5T_ENUM:
@@ -964,6 +976,8 @@ H5O_dtype_encode_helper(uint8_t **pp, const H5T_t *dt)
 
         case H5T_REFERENCE:
             flags |= (dt->shared->u.atomic.u.r.rtype & 0x0f);
+            if(dt->shared->u.atomic.u.r.opaque)
+                flags = (unsigned)(flags | (((unsigned)dt->shared->u.atomic.u.r.version & 0x0f) << 4));
             break;
 
         case H5T_ENUM:
diff --git a/src/H5Ofill.c b/src/H5Ofill.c
index df39d19..0cc58a6 100644
--- a/src/H5Ofill.c
+++ b/src/H5Ofill.c
@@ -742,7 +742,7 @@ H5O_fill_reset_dyn(H5O_fill_t *fill)
                 HGOTO_ERROR(H5E_OHDR, H5E_CANTCREATE, FAIL, "can't create scalar dataspace")
 
             /* Reclaim any variable length components of the fill value */
-            if(H5D_vlen_reclaim(fill_type_id, fill_space, fill->buf) < 0) {
+            if(H5T_reclaim(fill_type_id, fill_space, fill->buf) < 0) {
                 H5S_close(fill_space);
                 HGOTO_ERROR(H5E_OHDR, H5E_BADITER, FAIL, "unable to reclaim variable-length fill value data")
             } /* end if */
diff --git a/src/H5Oprivate.h b/src/H5Oprivate.h
index bcb8299..54e8ec8 100644
--- a/src/H5Oprivate.h
+++ b/src/H5Oprivate.h
@@ -981,8 +981,8 @@ H5_DLL herr_t H5O_are_mdc_flushes_disabled(H5O_loc_t *oloc, hbool_t *are_disable
 H5_DLL herr_t H5O_copy_header_map(const H5O_loc_t *oloc_src, H5O_loc_t *oloc_dst /*out */,
     H5O_copy_t *cpy_info, hbool_t inc_depth,
     H5O_type_t *obj_type, void **udata);
-H5_DLL herr_t H5O_copy_expand_ref(H5F_t *file_src, void *_src_ref, 
-    H5F_t *file_dst, void *_dst_ref, size_t ref_count, H5R_type_t ref_type,
+H5_DLL herr_t H5O_copy_expand_ref(H5F_t *file_src, hid_t tid_src, H5T_t *dt_src,
+    void *buf_src, size_t nbytes_src, H5F_t *file_dst, void *buf_dst,
     H5O_copy_t *cpy_info);
 H5_DLL herr_t H5O_copy(const H5G_loc_t *src_loc, const char *src_name,
     H5G_loc_t *dst_loc, const char *dst_name, hid_t ocpypl_id, hid_t lcpl_id);
diff --git a/src/H5Pint.c b/src/H5Pint.c
index 36367d7..2911eef 100644
--- a/src/H5Pint.c
+++ b/src/H5Pint.c
@@ -169,6 +169,8 @@ hid_t H5P_CLS_STRING_CREATE_ID_g                = H5I_INVALID_HID;
 H5P_genclass_t *H5P_CLS_STRING_CREATE_g         = NULL;
 hid_t H5P_CLS_VOL_INITIALIZE_ID_g               = H5I_INVALID_HID;
 H5P_genclass_t *H5P_CLS_VOL_INITIALIZE_g        = NULL;
+hid_t H5P_CLS_REFERENCE_ACCESS_ID_g             = H5I_INVALID_HID;
+H5P_genclass_t *H5P_CLS_REFERENCE_ACCESS_g      = NULL;
 
 /*
  * Predefined property lists for each predefined class. These are initialized
@@ -192,6 +194,7 @@ hid_t H5P_LST_OBJECT_COPY_ID_g          = H5I_INVALID_HID;
 hid_t H5P_LST_LINK_CREATE_ID_g          = H5I_INVALID_HID;
 hid_t H5P_LST_LINK_ACCESS_ID_g          = H5I_INVALID_HID;
 hid_t H5P_LST_VOL_INITIALIZE_ID_g       = H5I_INVALID_HID;
+hid_t H5P_LST_REFERENCE_ACCESS_ID_g     = H5I_INVALID_HID;
 
 /* Root property list class library initialization object */
 const H5P_libclass_t H5P_CLS_ROOT[1] = {{
@@ -312,6 +315,25 @@ const H5P_libclass_t H5P_CLS_VINI[1] = {{
     NULL 		        /* Class close callback info    */
 }};
 
+/* Reference access property list class library initialization object */
+/* (move to proper source code file when used for real) */
+const H5P_libclass_t H5P_CLS_RACC[1] = {{
+    "reference access",             /* Class name for debugging     */
+    H5P_TYPE_REFERENCE_ACCESS,      /* Class type                   */
+
+    &H5P_CLS_FILE_ACCESS_g,         /* Parent class                         */
+    &H5P_CLS_REFERENCE_ACCESS_g,    /* Pointer to class                     */
+    &H5P_CLS_REFERENCE_ACCESS_ID_g, /* Pointer to class ID                  */
+    &H5P_LST_REFERENCE_ACCESS_ID_g, /* Pointer to default property list ID  */
+    NULL,                           /* Default property registration routine*/
+
+    NULL,                           /* Class creation callback              */
+    NULL,                           /* Class creation callback info         */
+    NULL,                           /* Class copy callback                  */
+    NULL,                           /* Class copy callback info             */
+    NULL,                           /* Class close callback                 */
+    NULL                            /* Class close callback info            */
+}};
 
 /* Library property list classes defined in other code modules */
 /* (And not present in src/H5Pprivate.h) */
@@ -364,7 +386,8 @@ static H5P_libclass_t const * const init_class[] = {
     H5P_CLS_ACRT,       /* Attribute creation */
     H5P_CLS_AACC,       /* Attribute access */
     H5P_CLS_LCRT,       /* Link creation */
-    H5P_CLS_VINI        /* VOL initialization */
+    H5P_CLS_VINI,       /* VOL initialization */
+    H5P_CLS_RACC        /* Reference access */
 };
 
 /* Declare a free list to manage the H5P_genclass_t struct */
@@ -440,7 +463,7 @@ H5P__init_package(void)
     FUNC_ENTER_PACKAGE
 
     /* Sanity check */
-    HDcompile_assert(H5P_TYPE_MAP_ACCESS == (H5P_TYPE_MAX_TYPE - 1));
+    HDcompile_assert(H5P_TYPE_REFERENCE_ACCESS == (H5P_TYPE_MAX_TYPE - 1));
 
     /*
      * Initialize the Generic Property class & object groups.
@@ -564,6 +587,7 @@ H5P_term_package(void)
                         H5P_LST_LINK_CREATE_ID_g =
                         H5P_LST_LINK_ACCESS_ID_g =
                         H5P_LST_VOL_INITIALIZE_ID_g =
+                        H5P_LST_REFERENCE_ACCESS_ID_g =
                         H5P_LST_FILE_MOUNT_ID_g = H5I_INVALID_HID;
                 } /* end if */
             } /* end if */
@@ -594,6 +618,7 @@ H5P_term_package(void)
                         H5P_CLS_LINK_CREATE_g =
                         H5P_CLS_LINK_ACCESS_g =
                         H5P_CLS_VOL_INITIALIZE_g =
+                        H5P_CLS_REFERENCE_ACCESS_g =
                         H5P_CLS_FILE_MOUNT_g = NULL;
 
                         H5P_CLS_ROOT_ID_g =
@@ -616,6 +641,7 @@ H5P_term_package(void)
                         H5P_CLS_LINK_CREATE_ID_g =
                         H5P_CLS_LINK_ACCESS_ID_g =
                         H5P_CLS_VOL_INITIALIZE_ID_g =
+                        H5P_CLS_REFERENCE_ACCESS_ID_g =
                         H5P_CLS_FILE_MOUNT_ID_g = H5I_INVALID_HID;
                 } /* end if */
             } /* end if */
@@ -5453,8 +5479,8 @@ H5P__new_plist_of_type(H5P_plist_type_t type)
     FUNC_ENTER_PACKAGE
 
     /* Sanity checks */
-    HDcompile_assert(H5P_TYPE_MAP_ACCESS == (H5P_TYPE_MAX_TYPE - 1));
-    HDassert(type >= H5P_TYPE_USER && type <= H5P_TYPE_MAP_ACCESS);
+    HDcompile_assert(H5P_TYPE_REFERENCE_ACCESS == (H5P_TYPE_MAX_TYPE - 1));
+    HDassert(type >= H5P_TYPE_USER && type <= H5P_TYPE_REFERENCE_ACCESS);
 
     /* Check arguments */
     if(type == H5P_TYPE_USER)
@@ -5544,6 +5570,10 @@ H5P__new_plist_of_type(H5P_plist_type_t type)
             class_id = H5P_CLS_VOL_INITIALIZE_ID_g;
             break;
 
+        case H5P_TYPE_REFERENCE_ACCESS:
+            class_id = H5P_CLS_REFERENCE_ACCESS_ID_g;
+            break;
+
         case H5P_TYPE_USER:     /* shut compiler warnings up */
         case H5P_TYPE_ROOT:
         case H5P_TYPE_MAX_TYPE:
diff --git a/src/H5Pprivate.h b/src/H5Pprivate.h
index 9fc1acc..f7253a0 100644
--- a/src/H5Pprivate.h
+++ b/src/H5Pprivate.h
@@ -81,6 +81,7 @@ typedef enum H5P_plist_type_t {
     H5P_TYPE_VOL_INITIALIZE    = 19,
     H5P_TYPE_MAP_CREATE        = 20,
     H5P_TYPE_MAP_ACCESS        = 21,
+    H5P_TYPE_REFERENCE_ACCESS  = 22,
     H5P_TYPE_MAX_TYPE
 } H5P_plist_type_t;
 
diff --git a/src/H5Ppublic.h b/src/H5Ppublic.h
index 9f26b8b..bb33561 100644
--- a/src/H5Ppublic.h
+++ b/src/H5Ppublic.h
@@ -71,6 +71,7 @@
 #define H5P_LINK_CREATE         (H5OPEN H5P_CLS_LINK_CREATE_ID_g)
 #define H5P_LINK_ACCESS         (H5OPEN H5P_CLS_LINK_ACCESS_ID_g)
 #define H5P_VOL_INITIALIZE      (H5OPEN H5P_CLS_VOL_INITIALIZE_ID_g)
+#define H5P_REFERENCE_ACCESS    (H5OPEN H5P_CLS_REFERENCE_ACCESS_ID_g)
 
 /*
  * The library's default property lists
@@ -93,6 +94,7 @@
 #define H5P_LINK_CREATE_DEFAULT        (H5OPEN H5P_LST_LINK_CREATE_ID_g)
 #define H5P_LINK_ACCESS_DEFAULT        (H5OPEN H5P_LST_LINK_ACCESS_ID_g)
 #define H5P_VOL_INITIALIZE_DEFAULT     (H5OPEN H5P_LST_VOL_INITIALIZE_ID_g)
+#define H5P_REFERENCE_ACCESS_DEFAULT   (H5OPEN H5P_LST_REFERENCE_ACCESS_ID_g)
 
 /* Common creation order flags (for links in groups and attributes on objects) */
 #define H5P_CRT_ORDER_TRACKED           0x0001
@@ -204,6 +206,7 @@ H5_DLLVAR hid_t H5P_CLS_OBJECT_COPY_ID_g;
 H5_DLLVAR hid_t H5P_CLS_LINK_CREATE_ID_g;
 H5_DLLVAR hid_t H5P_CLS_LINK_ACCESS_ID_g;
 H5_DLLVAR hid_t H5P_CLS_VOL_INITIALIZE_ID_g;
+H5_DLLVAR hid_t H5P_CLS_REFERENCE_ACCESS_ID_g;
 
 /* Default roperty list IDs */
 /* (Internal to library, do not use!  Use macros above) */
@@ -225,6 +228,7 @@ H5_DLLVAR hid_t H5P_LST_OBJECT_COPY_ID_g;
 H5_DLLVAR hid_t H5P_LST_LINK_CREATE_ID_g;
 H5_DLLVAR hid_t H5P_LST_LINK_ACCESS_ID_g;
 H5_DLLVAR hid_t H5P_LST_VOL_INITIALIZE_ID_g;
+H5_DLLVAR hid_t H5P_LST_REFERENCE_ACCESS_ID_g;
 
 /*********************/
 /* Public Prototypes */
diff --git a/src/H5R.c b/src/H5R.c
index 7d3686e..11b75ca 100644
--- a/src/H5R.c
+++ b/src/H5R.c
@@ -11,22 +11,24 @@
  * help@hdfgroup.org.                                                        *
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
+/*
+ * Purpose:     Reference routines.
+ */
+
 /****************/
 /* Module Setup */
 /****************/
 
 #include "H5Rmodule.h"          /* This source code file is part of the H5R module */
 
-
 /***********/
 /* Headers */
 /***********/
 #include "H5private.h"          /* Generic Functions                        */
-#include "H5ACprivate.h"        /* Metadata cache                           */
 #include "H5CXprivate.h"        /* API Contexts                             */
 #include "H5Eprivate.h"         /* Error handling                           */
-#include "H5Gprivate.h"         /* Groups                                   */
 #include "H5Iprivate.h"         /* IDs                                      */
+#include "H5MMprivate.h"        /* Memory management                        */
 #include "H5Rpkg.h"             /* References                               */
 #include "H5Sprivate.h"         /* Dataspaces                               */
 
@@ -61,330 +63,825 @@
 /*******************/
 
 
-/*--------------------------------------------------------------------------
- NAME
-    H5Rcreate
- PURPOSE
-    Creates a particular kind of reference for the user
- USAGE
-    herr_t H5Rcreate(ref, loc_id, name, ref_type, space_id)
-        void *ref;          OUT: Reference created
-        hid_t loc_id;       IN: Location ID used to locate object pointed to
-        const char *name;   IN: Name of object at location LOC_ID of object
-                                    pointed to
-        H5R_type_t ref_type;    IN: Type of reference to create
-        hid_t space_id;     IN: Dataspace ID with selection, used for Dataset
-                                    Region references.
-
- RETURNS
-    Non-negative on success/Negative on failure
- DESCRIPTION
-    Creates a particular type of reference specified with REF_TYPE, in the
-    space pointed to by REF.  The LOC_ID and NAME are used to locate the object
-    pointed to and the SPACE_ID is used to choose the region pointed to (for
-    Dataset Region references).
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
- EXAMPLES
- REVISION LOG
---------------------------------------------------------------------------*/
+/*-------------------------------------------------------------------------
+ * Function:    H5Rcreate_object
+ *
+ * Purpose: Creates an object reference. The LOC_ID and NAME are used to locate
+ * the object pointed to.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
 herr_t
-H5Rcreate(void *ref, hid_t loc_id, const char *name, H5R_type_t ref_type, hid_t space_id)
+H5Rcreate_object(hid_t loc_id, const char *name, H5R_ref_t *ref_ptr)
 {
-    H5VL_object_t      *vol_obj = NULL;         /* Object token of loc_id */
-    H5VL_loc_params_t   loc_params;
-    herr_t              ret_value;              /* Return value */
+    H5VL_object_t *vol_obj = NULL;  /* Object token of loc_id */
+    H5I_type_t obj_type;            /* Object type of loc_id */
+    hid_t file_id = H5I_INVALID_HID;/* File ID */
+    H5VL_object_t *vol_obj_file = NULL; /* Object token of file_id */
+    H5VL_loc_params_t loc_params;   /* Location parameters */
+    H5VL_token_t obj_token = {0};   /* Object token */
+    H5VL_file_cont_info_t cont_info = {H5VL_CONTAINER_INFO_VERSION, 0, 0, 0};
+    herr_t ret_value = SUCCEED;     /* Return value */
 
     FUNC_ENTER_API(FAIL)
-    H5TRACE5("e", "*xi*sRti", ref, loc_id, name, ref_type, space_id);
+    H5TRACE3("e", "i*s*Rr", loc_id, name, ref_ptr);
 
     /* Check args */
-    if (ref == NULL)
+    if(ref_ptr == NULL)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference pointer")
     if(!name || !*name)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no name given")
-    if(ref_type <= H5R_BADTYPE || ref_type >= H5R_MAXTYPE)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference type")
-    if(ref_type != H5R_OBJECT && ref_type != H5R_DATASET_REGION)
-        HGOTO_ERROR(H5E_ARGS, H5E_UNSUPPORTED, FAIL, "reference type not supported")
-    if(space_id == (-1) && ref_type == H5R_DATASET_REGION)
+
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(loc_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Get object type */
+    if((obj_type = H5I_get_type(loc_id)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Get the file for the object */
+    if((file_id = H5F_get_file_id(loc_id, obj_type, FALSE)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file or file object")
+
+    /* Retrieve VOL file object */
+    if(NULL == (vol_obj_file = H5VL_vol_object(file_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Get container info */
+    if(H5VL_file_get(vol_obj_file, H5VL_FILE_GET_CONT_INFO, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &cont_info) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, FAIL, "unable to get container info")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_NAME;
+    loc_params.loc_data.loc_by_name.name = name;
+    loc_params.obj_type = obj_type;
+
+    /* Get the object token */
+    if(H5VL_object_specific(vol_obj, &loc_params, H5VL_OBJECT_LOOKUP, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, obj_token) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, FAIL, "unable to retrieve object token")
+
+    /* Create the reference (do not pass filename, since file_id is attached) */
+    HDmemset(ref_ptr, 0, H5R_REF_BUF_SIZE);
+    if(H5R__create_object((const H5VL_token_t *)&obj_token, cont_info.token_size, (H5R_ref_priv_t *)ref_ptr) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCREATE, FAIL, "unable to create object reference")
+
+    /* Attach loc_id to reference and hold reference to it */
+    if(H5R__set_loc_id((H5R_ref_priv_t *)ref_ptr, file_id, TRUE) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, FAIL, "unable to attach location id to reference")
+
+done:
+    if(file_id != H5I_INVALID_HID && H5I_dec_ref(file_id) < 0)
+        HDONE_ERROR(H5E_REFERENCE, H5E_CANTDEC, FAIL, "unable to decrement refcount on file")
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Rcreate_object() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rcreate_region
+ *
+ * Purpose: Creates a region reference. The LOC_ID and NAME are used to locate
+ * the object pointed to and the SPACE_ID is used to choose the region pointed
+ * to.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Rcreate_region(hid_t loc_id, const char *name, hid_t space_id,
+    H5R_ref_t *ref_ptr)
+{
+    H5VL_object_t *vol_obj = NULL;  /* Object token of loc_id */
+    H5I_type_t obj_type;            /* Object type of loc_id */
+    hid_t file_id = H5I_INVALID_HID;/* File ID */
+    H5VL_object_t *vol_obj_file = NULL; /* Object token of file_id */
+    H5VL_loc_params_t loc_params;   /* Location parameters */
+    H5VL_token_t obj_token = {0};   /* Object token */
+    H5VL_file_cont_info_t cont_info = {H5VL_CONTAINER_INFO_VERSION, 0, 0, 0};
+    struct H5S_t *space = NULL;     /* Pointer to dataspace containing region */
+    herr_t ret_value = SUCCEED;     /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE4("e", "i*si*Rr", loc_id, name, space_id, ref_ptr);
+
+    /* Check args */
+    if(ref_ptr == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference pointer")
+    if(!name || !*name)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no name given")
+    if((space_id == H5I_BADID) || (space_id == H5S_ALL))
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "reference region dataspace id must be valid")
+    if(NULL == (space = (struct H5S_t *)H5I_object_verify(space_id, H5I_DATASPACE)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataspace")
+
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(loc_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Get object type */
+    if((obj_type = H5I_get_type(loc_id)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Get the file for the object */
+    if((file_id = H5F_get_file_id(loc_id, obj_type, FALSE)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file or file object")
+
+    /* Retrieve VOL file object */
+    if(NULL == (vol_obj_file = H5VL_vol_object(file_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Get container info */
+    if(H5VL_file_get(vol_obj_file, H5VL_FILE_GET_CONT_INFO, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &cont_info) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, FAIL, "unable to get container info")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_NAME;
+    loc_params.loc_data.loc_by_name.name = name;
+    loc_params.obj_type = obj_type;
+
+    /* Get the object token */
+    if(H5VL_object_specific(vol_obj, &loc_params, H5VL_OBJECT_LOOKUP, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, obj_token) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, FAIL, "unable to retrieve object token")
+
+    /* Create the reference (do not pass filename, since file_id is attached) */
+    HDmemset(ref_ptr, 0, H5R_REF_BUF_SIZE);
+    if(H5R__create_region((const H5VL_token_t *)&obj_token, cont_info.token_size, space, (H5R_ref_priv_t *)ref_ptr) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCREATE, FAIL, "unable to create region reference")
+
+    /* Attach loc_id to reference and hold reference to it */
+    if(H5R__set_loc_id((H5R_ref_priv_t *)ref_ptr, file_id, TRUE) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, FAIL, "unable to attach location id to reference")
+
+done:
+    if(file_id != H5I_INVALID_HID && H5I_dec_ref(file_id) < 0)
+        HDONE_ERROR(H5E_REFERENCE, H5E_CANTDEC, H5I_INVALID_HID, "unable to decrement refcount on file")
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Rcreate_region() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rcreate_attr
+ *
+ * Purpose: Creates an attribute reference. The LOC_ID, NAME and ATTR_NAME are
+ * used to locate the attribute pointed to.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Rcreate_attr(hid_t loc_id, const char *name, const char *attr_name,
+    H5R_ref_t *ref_ptr)
+{
+    H5VL_object_t *vol_obj = NULL;  /* Object token of loc_id */
+    H5I_type_t obj_type;            /* Object type of loc_id */
+    hid_t file_id = H5I_INVALID_HID;/* File ID */
+    H5VL_object_t *vol_obj_file = NULL; /* Object token of file_id */
+    H5VL_loc_params_t loc_params;   /* Location parameters */
+    H5VL_token_t obj_token = {0};   /* Object token */
+    H5VL_file_cont_info_t cont_info = {H5VL_CONTAINER_INFO_VERSION, 0, 0, 0};
+    herr_t ret_value = SUCCEED;     /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE4("e", "i*s*s*Rr", loc_id, name, attr_name, ref_ptr);
+
+    /* Check args */
+    if(ref_ptr == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference pointer")
+    if(!name || !*name)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no name given")
+    if(!attr_name || !*attr_name)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no attribute name given")
+
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(loc_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Get object type */
+    if((obj_type = H5I_get_type(loc_id)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
 
-    /* Set up collective metadata if appropriate */
-    if(H5CX_set_loc(loc_id) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, FAIL, "can't set access property list info")
+    /* Get the file for the object */
+    if((file_id = H5F_get_file_id(loc_id, obj_type, FALSE)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file or file object")
+
+    /* Retrieve VOL file object */
+    if(NULL == (vol_obj_file = H5VL_vol_object(file_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Get container info */
+    if(H5VL_file_get(vol_obj_file, H5VL_FILE_GET_CONT_INFO, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &cont_info) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, FAIL, "unable to get container info")
 
     /* Set location parameters */
-    loc_params.type         = H5VL_OBJECT_BY_SELF;
-    loc_params.obj_type     = H5I_get_type(loc_id);
+    loc_params.type = H5VL_OBJECT_BY_NAME;
+    loc_params.loc_data.loc_by_name.name = name;
+    loc_params.obj_type = obj_type;
+
+    /* Get the object token */
+    if(H5VL_object_specific(vol_obj, &loc_params, H5VL_OBJECT_LOOKUP, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, obj_token) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, FAIL, "unable to retrieve object token")
+
+    /* Create the reference (do not pass filename, since file_id is attached) */
+    HDmemset(ref_ptr, 0, H5R_REF_BUF_SIZE);
+    if(H5R__create_attr((const H5VL_token_t *)&obj_token, cont_info.token_size, attr_name, (H5R_ref_priv_t *)ref_ptr) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCREATE, FAIL, "unable to create attribute reference")
+
+    /* Attach loc_id to reference and hold reference to it */
+    if(H5R__set_loc_id((H5R_ref_priv_t *)ref_ptr, file_id, TRUE) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, FAIL, "unable to attach location id to reference")
+
+done:
+    if(file_id != H5I_INVALID_HID && H5I_dec_ref(file_id) < 0)
+        HDONE_ERROR(H5E_REFERENCE, H5E_CANTDEC, H5I_INVALID_HID, "unable to decrement refcount on file")
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Rcreate_attr() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rdestroy
+ *
+ * Purpose: Destroy reference and free resources allocated during H5Rcreate.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Rdestroy(H5R_ref_t *ref_ptr)
+{
+    herr_t ret_value = SUCCEED;                 /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE1("e", "*Rr", ref_ptr);
+
+    /* Check args */
+    if(NULL == ref_ptr)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid reference pointer")
+
+    /* Destroy reference */
+    if(H5R__destroy((H5R_ref_priv_t *)ref_ptr) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTFREE, FAIL, "unable to destroy reference")
+
+    /* Memset back to 0 for safety */
+    HDmemset(ref_ptr, 0, H5R_REF_BUF_SIZE);
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Rdestroy() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rget_type
+ *
+ * Purpose: Given a reference to some object, return the type of that reference.
+ *
+ * Return:  Reference type/H5R_BADTYPE on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+H5R_type_t
+H5Rget_type(const H5R_ref_t *ref_ptr)
+{
+    H5R_type_t ret_value;   /* Return value */
+
+    FUNC_ENTER_API(H5R_BADTYPE)
+    H5TRACE1("Rt", "*Rr", ref_ptr);
+
+    /* Check args */
+    if(NULL == ref_ptr)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5R_BADTYPE, "invalid reference pointer")
+
+    /* Get reference type */
+    ret_value = H5R__get_type((const H5R_ref_priv_t *)ref_ptr);
+    if((ret_value <= H5R_BADTYPE) || (ret_value >= H5R_MAXTYPE))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_BADVALUE, H5R_BADTYPE, "invalid reference type")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Rget_type() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Requal
+ *
+ * Purpose: Compare two references
+ *
+ * Return:  TRUE if equal, FALSE if unequal, FAIL if error
+ *
+ *-------------------------------------------------------------------------
+ */
+htri_t
+H5Requal(const H5R_ref_t *ref1_ptr, const H5R_ref_t *ref2_ptr)
+{
+    htri_t ret_value;   /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE2("t", "*Rr*Rr", ref1_ptr, ref2_ptr);
+
+    /* Check args */
+    if(!ref1_ptr || !ref2_ptr)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference pointer")
+
+    /* Compare references */
+    if((ret_value = H5R__equal((const H5R_ref_priv_t *)ref2_ptr, (const H5R_ref_priv_t *)ref2_ptr)) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOMPARE, FAIL, "cannot compare references")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Requal() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rcopy
+ *
+ * Purpose: Copy a reference
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Rcopy(const H5R_ref_t *src_ref_ptr, H5R_ref_t *dst_ref_ptr)
+{
+    herr_t ret_value = SUCCEED; /* Return value */
 
-    /* Get the file object */
-    if (NULL == (vol_obj = (H5VL_object_t *)H5I_object(loc_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid file identifier")
+    FUNC_ENTER_API(FAIL)
+    H5TRACE2("e", "*Rr*Rr", src_ref_ptr, dst_ref_ptr);
 
-    /* Set up collective metadata if appropriate */
-    if(H5CX_set_loc(loc_id) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, FAIL, "can't set access property list info")
+    /* Check args */
+    if(NULL == src_ref_ptr || NULL == dst_ref_ptr)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid reference pointer")
 
-    /* Create reference */
-    if((ret_value = H5VL_object_specific(vol_obj, &loc_params, H5VL_REF_CREATE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, ref, name, (int)ref_type, space_id)) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCREATE, FAIL, "unable to create reference")
+    /* Copy reference */
+    if(H5R__copy((const H5R_ref_priv_t *)src_ref_ptr, (H5R_ref_priv_t *)dst_ref_ptr) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOPY, FAIL, "cannot copy reference")
 
 done:
     FUNC_LEAVE_API(ret_value)
-}   /* end H5Rcreate() */
+} /* end H5Rcopy() */
 
 
-/*--------------------------------------------------------------------------
- NAME
-    H5Rdereference2
- PURPOSE
-    Opens the HDF5 object referenced.
- USAGE
-    hid_t H5Rdereference2(ref)
-        hid_t id;       IN: Dataset reference object is in or location ID of
-                            object that the dataset is located within.
-        hid_t oapl_id;  IN: Property list of the object being referenced.
-        H5R_type_t ref_type;    IN: Type of reference to create
-        void *ref;      IN: Reference to open.
-
- RETURNS
-    Valid ID on success, H5I_INVALID_HID on failure
- DESCRIPTION
-    Given a reference to some object, open that object and return an ID for
-    that object.
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
- EXAMPLES
- REVISION LOG
-    Raymond Lu
-    13 July 2011
-    I added the OAPL_ID parameter for the object being referenced.  It only
-    supports dataset access property list currently.
---------------------------------------------------------------------------*/
+/*-------------------------------------------------------------------------
+ * Function:    H5Ropen_object
+ *
+ * Purpose: Given a reference to some object, open that object and return an
+ * ID for that object.
+ *
+ * Return:  Valid ID on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
 hid_t
-H5Rdereference2(hid_t obj_id, hid_t oapl_id, H5R_type_t ref_type, const void *_ref)
+H5Ropen_object(const H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t oapl_id)
 {
-    H5VL_object_t *vol_obj = NULL;        /* object token of loc_id */
-    H5I_type_t opened_type;
-    void *opened_obj = NULL;
-    H5VL_loc_params_t loc_params;
-    hid_t ret_value = H5I_INVALID_HID;	/* Return value */
+    hid_t loc_id;                       /* Reference location ID */
+    H5VL_object_t *vol_obj = NULL;      /* Object token of loc_id */
+    H5VL_loc_params_t loc_params;       /* Location parameters */
+    H5VL_token_t obj_token = {0};       /* Object token */
+    H5I_type_t opened_type;             /* Opened object type */
+    void *opened_obj = NULL;            /* Opened object */
+    hid_t ret_value = H5I_INVALID_HID;  /* Return value */
 
     FUNC_ENTER_API(H5I_INVALID_HID)
-    H5TRACE4("i", "iiRt*x", obj_id, oapl_id, ref_type, _ref);
+    H5TRACE3("i", "*Rrii", ref_ptr, rapl_id, oapl_id);
 
     /* Check args */
+    if(ref_ptr == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference pointer")
+    if(H5R__get_type((const H5R_ref_priv_t *)ref_ptr) <= H5R_BADTYPE
+        || H5R__get_type((const H5R_ref_priv_t *)ref_ptr) >= H5R_MAXTYPE)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference type")
+    if(rapl_id < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a property list")
     if(oapl_id < 0)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a property list")
-    if(ref_type <= H5R_BADTYPE || ref_type >= H5R_MAXTYPE)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference type")
-    if(_ref == NULL)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference pointer")
+
+    /* Retrieve loc_id from reference */
+    if(H5I_INVALID_HID == (loc_id = H5R__get_loc_id((const H5R_ref_priv_t *)ref_ptr))) {
+        /* Attempt to re-open file and pass rapl_id as a fapl_id */
+        if((loc_id = H5R__reopen_file((H5R_ref_priv_t *)ref_ptr, rapl_id)) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENFILE, H5I_INVALID_HID, "cannot re-open referenced file")
+    }
+
+    /* Get object token */
+    if(H5R__get_obj_token((const H5R_ref_priv_t *)ref_ptr, &obj_token, NULL) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, H5I_INVALID_HID, "unable to get object token")
 
     /* Verify access property list and set up collective metadata if appropriate */
-    if(H5CX_set_apl(&oapl_id, H5P_CLS_DACC, obj_id, FALSE) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, FAIL, "can't set access property list info")
+    if(H5CX_set_apl(&oapl_id, H5P_CLS_DACC, loc_id, FALSE) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, H5I_INVALID_HID, "can't set access property list info")
 
     /* Get the VOL object */
-    if(NULL == (vol_obj = H5VL_vol_object(obj_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid file identifier")
+    if(NULL == (vol_obj = H5VL_vol_object(loc_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
 
     /* Set location parameters */
-    loc_params.type                             = H5VL_OBJECT_BY_REF;
-    loc_params.loc_data.loc_by_ref.ref_type     = ref_type;
-    loc_params.loc_data.loc_by_ref._ref         = _ref;
-    loc_params.loc_data.loc_by_ref.lapl_id      = oapl_id;
-    loc_params.obj_type                         = H5I_get_type(obj_id);
+    loc_params.type = H5VL_OBJECT_BY_TOKEN;
+    loc_params.loc_data.loc_by_token.token = obj_token;
+    loc_params.obj_type = H5I_get_type(loc_id);
 
-    /* Dereference */
+    /* Open object by token */
     if(NULL == (opened_obj = H5VL_object_open(vol_obj, &loc_params, &opened_type, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to dereference object")
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to open object by token")
 
+    /* Register object */
     if((ret_value = H5VL_register(opened_type, opened_obj, vol_obj->connector, TRUE)) < 0)
         HGOTO_ERROR(H5E_REFERENCE, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to register object handle")
 
 done:
     FUNC_LEAVE_API(ret_value)
-}   /* end H5Rdereference2() */
+} /* end H5Ropen_object() */
 
 
-/*--------------------------------------------------------------------------
- NAME
-    H5Rget_region
- PURPOSE
-    Retrieves a dataspace with the region pointed to selected.
- USAGE
-    hid_t H5Rget_region(id, ref_type, ref)
-        hid_t id;       IN: Dataset reference object is in or location ID of
-                            object that the dataset is located within.
-        H5R_type_t ref_type;    IN: Type of reference to get region of
-        void *ref;        IN: Reference to open.
-
- RETURNS
-    Valid ID on success, H5I_INVALID_HID on failure
- DESCRIPTION
-    Given a reference to some object, creates a copy of the dataset pointed
-    to's dataspace and defines a selection in the copy which is the region
-    pointed to.
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
- EXAMPLES
- REVISION LOG
---------------------------------------------------------------------------*/
+/*-------------------------------------------------------------------------
+ * Function:    H5Ropen_region
+ *
+ * Purpose: Given a reference to some object, creates a copy of the dataset
+ * pointed to's dataspace and defines a selection in the copy which is the
+ * region pointed to.
+ *
+ * Return:  Valid ID on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
 hid_t
-H5Rget_region(hid_t id, H5R_type_t ref_type, const void *ref)
+H5Ropen_region(const H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t oapl_id)
 {
-    H5VL_object_t    *vol_obj = NULL;        /* object token of loc_id */
-    H5VL_loc_params_t loc_params;
-    hid_t ret_value = H5I_INVALID_HID;	/* Return value */
+    hid_t loc_id;                           /* Reference location ID */
+    H5VL_object_t *vol_obj = NULL;          /* Object token of loc_id */
+    H5VL_loc_params_t loc_params;           /* Location parameters */
+    H5VL_token_t obj_token = {0};           /* Object token */
+    H5I_type_t opened_type;                 /* Opened object type */
+    void *opened_obj = NULL;                /* Opened object */
+    hid_t opened_obj_id = H5I_INVALID_HID;  /* Opened object ID */
+    H5S_t *space = NULL;                    /* Dataspace pointer (copy) */
+    hid_t space_id = H5I_INVALID_HID;       /* Dataspace ID */
+    hid_t ret_value = H5I_INVALID_HID;      /* Return value */
 
     FUNC_ENTER_API(H5I_INVALID_HID)
-    H5TRACE3("i", "iRt*x", id, ref_type, ref);
+    H5TRACE3("i", "*Rrii", ref_ptr, rapl_id, oapl_id);
 
     /* Check args */
-    if(ref_type != H5R_DATASET_REGION)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference type")
-    if(ref == NULL)
+    if(ref_ptr == NULL)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference pointer")
+    if((H5R__get_type((const H5R_ref_priv_t *)ref_ptr) != H5R_DATASET_REGION1)
+        && (H5R__get_type((const H5R_ref_priv_t *)ref_ptr) != H5R_DATASET_REGION2))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference type")
+    if(rapl_id < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a property list")
+    if(oapl_id < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a property list")
+
+    /* Retrieve loc_id from reference */
+    if(H5I_INVALID_HID == (loc_id = H5R__get_loc_id((const H5R_ref_priv_t *)ref_ptr))) {
+        /* Attempt to re-open file and pass rapl_id as a fapl_id */
+        if((loc_id = H5R__reopen_file((H5R_ref_priv_t *)ref_ptr, rapl_id)) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENFILE, H5I_INVALID_HID, "cannot re-open referenced file")
+    }
+
+    /* Get object token */
+    if(H5R__get_obj_token((const H5R_ref_priv_t *)ref_ptr, &obj_token, NULL) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, H5I_INVALID_HID, "unable to get object token")
+
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(loc_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
 
     /* Set location parameters */
-    loc_params.type         = H5VL_OBJECT_BY_SELF;
-    loc_params.obj_type     = H5I_get_type(id);
+    loc_params.type = H5VL_OBJECT_BY_TOKEN;
+    loc_params.loc_data.loc_by_token.token = obj_token;
+    loc_params.obj_type = H5I_get_type(loc_id);
 
-    /* get the file object */
-    if(NULL == (vol_obj = (H5VL_object_t *)H5I_object(id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid file identifier")
+    /* Open object by token */
+    if(NULL == (opened_obj = H5VL_object_open(vol_obj, &loc_params, &opened_type, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to open object by token")
+
+    /* Register object */
+    if((opened_obj_id = H5VL_register(opened_type, opened_obj, vol_obj->connector, FALSE)) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to register object handle")
+
+    /* Get VOL object object */
+    if(NULL == (opened_obj = H5VL_vol_object(opened_obj_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
+
+    /* Get dataspace from object */
+    if(H5VL_dataset_get(opened_obj, H5VL_DATASET_GET_SPACE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &space_id) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, H5I_INVALID_HID, "unable to get dataspace from dataset")
+    if(NULL == (space = (struct H5S_t *)H5I_object_verify(space_id, H5I_DATASPACE)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a dataspace")
 
     /* Get the dataspace with the correct region selected */
-    if(H5VL_object_get(vol_obj, &loc_params, H5VL_REF_GET_REGION, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &ret_value, (int)ref_type, ref) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, H5I_INVALID_HID, "unable to retrieve dataspace")
+    if(H5R__get_region((const H5R_ref_priv_t *)ref_ptr, space) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, H5I_INVALID_HID, "unable to get selection on dataspace")
+
+    /* Simply return space_id */
+    ret_value = space_id;
+
+done:
+    if((opened_obj_id != H5I_INVALID_HID) && (H5I_dec_ref(opened_obj_id) < 0))
+        HDONE_ERROR(H5E_REFERENCE, H5E_CLOSEERROR, H5I_INVALID_HID, "can't close object")
+    if(H5I_INVALID_HID == ret_value) /* Cleanup on failure */
+        if((space_id != H5I_INVALID_HID) && (H5I_dec_ref(space_id) < 0))
+        HDONE_ERROR(H5E_REFERENCE, H5E_CLOSEERROR, H5I_INVALID_HID, "can't close dataspace")
+
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Ropen_region() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Ropen_attr
+ *
+ * Purpose: Given a reference to some attribute, open that attribute and
+ * return an ID for that attribute.
+ *
+ * Return:  Valid ID on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+hid_t
+H5Ropen_attr(const H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t aapl_id)
+{
+    hid_t loc_id;                           /* Reference location ID */
+    H5VL_object_t *vol_obj = NULL;          /* Object token of loc_id */
+    H5VL_loc_params_t loc_params;           /* Location parameters */
+    H5VL_token_t obj_token = {0};           /* Object token */
+    H5I_type_t opened_type;                 /* Opened object type */
+    void *opened_obj = NULL;                /* Opened object */
+    hid_t opened_obj_id = H5I_INVALID_HID;  /* Opened object ID */
+    void *opened_attr = NULL;               /* Opened attribute */
+    hid_t ret_value = H5I_INVALID_HID;      /* Return value */
+
+    FUNC_ENTER_API(H5I_INVALID_HID)
+    H5TRACE3("i", "*Rrii", ref_ptr, rapl_id, aapl_id);
+
+    /* Check args */
+    if(ref_ptr == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference pointer")
+    if(H5R__get_type((const H5R_ref_priv_t *)ref_ptr) != H5R_ATTR)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference type")
+    if(rapl_id < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a property list")
+    if(aapl_id < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a property list")
+
+    /* Retrieve loc_id from reference */
+    if(H5I_INVALID_HID == (loc_id = H5R__get_loc_id((const H5R_ref_priv_t *)ref_ptr))) {
+        /* Attempt to re-open file and pass rapl_id as a fapl_id */
+        if((loc_id = H5R__reopen_file((H5R_ref_priv_t *)ref_ptr, rapl_id)) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENFILE, H5I_INVALID_HID, "cannot re-open referenced file")
+    }
+
+    /* Get object token */
+    if(H5R__get_obj_token((const H5R_ref_priv_t *)ref_ptr, &obj_token, NULL) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, H5I_INVALID_HID, "unable to get object token")
+
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(loc_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_TOKEN;
+    loc_params.loc_data.loc_by_token.token = obj_token;
+    loc_params.obj_type = H5I_get_type(loc_id);
+
+    /* Open object by token */
+    if(NULL == (opened_obj = H5VL_object_open(vol_obj, &loc_params, &opened_type, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to open object by token")
+
+    /* Register object */
+    if((opened_obj_id = H5VL_register(opened_type, opened_obj, vol_obj->connector, FALSE)) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to register object handle")
+
+    /* Verify access property list and set up collective metadata if appropriate */
+    if(H5CX_set_apl(&aapl_id, H5P_CLS_AACC, loc_id, FALSE) < 0)
+        HGOTO_ERROR(H5E_ATTR, H5E_CANTSET, H5I_INVALID_HID, "can't set access property list info")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_SELF;
+    loc_params.obj_type = opened_type;
+
+    /* Get VOL object object */
+    if(NULL == (opened_obj = H5VL_vol_object(opened_obj_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
+
+    /* Open the attribute */
+    if(NULL == (opened_attr = H5VL_attr_open(opened_obj, &loc_params, H5R_REF_ATTRNAME((const H5R_ref_priv_t *)ref_ptr), aapl_id, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
+        HGOTO_ERROR(H5E_ATTR, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to open attribute: '%s'", H5R_REF_ATTRNAME((const H5R_ref_priv_t *)ref_ptr))
+
+    /* Register the attribute and get an ID for it */
+    if((ret_value = H5VL_register(H5I_ATTR, opened_attr, vol_obj->connector, TRUE)) < 0)
+        HGOTO_ERROR(H5E_ATTR, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to atomize attribute handle")
 
 done:
+    if((opened_obj_id != H5I_INVALID_HID) && (H5I_dec_ref(opened_obj_id) < 0))
+        HDONE_ERROR(H5E_REFERENCE, H5E_CLOSEERROR, H5I_INVALID_HID, "can't close object")
+    if(H5I_INVALID_HID == ret_value) /* Cleanup on failure */
+        if(opened_attr && H5VL_attr_close(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
+            HDONE_ERROR(H5E_ATTR, H5E_CLOSEERROR, H5I_INVALID_HID, "can't close attribute")
+
     FUNC_LEAVE_API(ret_value)
-}   /* end H5Rget_region() */
+} /* end H5Ropen_attr() */
 
 
-/*--------------------------------------------------------------------------
- NAME
-    H5Rget_obj_type2
- PURPOSE
-    Retrieves the type of object that an object reference points to
- USAGE
-    herr_t H5Rget_obj_type2(id, ref_type, ref, obj_type)
-        hid_t id;       IN: Dataset reference object is in or location ID of
-                            object that the dataset is located within.
-        H5R_type_t ref_type;    IN: Type of reference to query
-        void *ref;          IN: Reference to query.
-        H5O_type_t *obj_type;   OUT: Type of object reference points to
-
- RETURNS
-    Non-negative on success/Negative on failure
- DESCRIPTION
-    Given a reference to some object, this function retrieves the type of
-    object pointed to.
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
- EXAMPLES
- REVISION LOG
---------------------------------------------------------------------------*/
+/*-------------------------------------------------------------------------
+ * Function:    H5Rget_obj_type3
+ *
+ * Purpose: Given a reference to some object, this function returns the type
+ * of object pointed to.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
 herr_t
-H5Rget_obj_type2(hid_t id, H5R_type_t ref_type, const void *ref,
-    H5O_type_t *obj_type)
+H5Rget_obj_type3(const H5R_ref_t *ref_ptr, hid_t rapl_id, H5O_type_t *obj_type)
 {
-    H5VL_object_t    *vol_obj = NULL;        /* object token of loc_id */
-    H5VL_loc_params_t loc_params;
-    herr_t ret_value = SUCCEED; /* Return value */
+    hid_t loc_id;                       /* Reference location ID */
+    H5VL_object_t *vol_obj = NULL;      /* Object token of loc_id */
+    H5VL_loc_params_t loc_params;       /* Location parameters */
+    H5VL_token_t obj_token = {0};       /* Object token */
+    herr_t ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_API(FAIL)
-    H5TRACE4("e", "iRt*x*Ot", id, ref_type, ref, obj_type);
+    H5TRACE3("e", "*Rri*Ot", ref_ptr, rapl_id, obj_type);
 
     /* Check args */
-    if(ref_type <= H5R_BADTYPE || ref_type >= H5R_MAXTYPE)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference type")
-    if(ref == NULL)
+    if(ref_ptr == NULL)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference pointer")
+    if(H5R__get_type((const H5R_ref_priv_t *)ref_ptr) <= H5R_BADTYPE
+        || H5R__get_type((const H5R_ref_priv_t *)ref_ptr) >= H5R_MAXTYPE)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference type")
+    if(rapl_id < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a property list")
 
-    /* Set location parameters */
-    loc_params.type         = H5VL_OBJECT_BY_SELF;
-    loc_params.obj_type     = H5I_get_type(id);
+    /* Retrieve loc_id from reference */
+    if(H5I_INVALID_HID == (loc_id = H5R__get_loc_id((const H5R_ref_priv_t *)ref_ptr))) {
+        /* Attempt to re-open file and pass rapl_id as a fapl_id */
+        if((loc_id = H5R__reopen_file((H5R_ref_priv_t *)ref_ptr, rapl_id)) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENFILE, FAIL, "cannot re-open referenced file")
+    }
+
+    /* Get object token */
+    if(H5R__get_obj_token((const H5R_ref_priv_t *)ref_ptr, &obj_token, NULL) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, FAIL, "unable to get object token")
 
-    /* Get the file object */
-    if(NULL == (vol_obj = (H5VL_object_t *)H5I_object(id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid file identifier")
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(loc_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_TOKEN;
+    loc_params.loc_data.loc_by_token.token = obj_token;
+    loc_params.obj_type = H5I_get_type(loc_id);
 
-    /* Get the object type */
-    if(H5VL_object_get(vol_obj, &loc_params, H5VL_REF_GET_TYPE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, obj_type, (int)ref_type, ref) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, FAIL, "unable to determine object type")
+    /* Retrieve object's type */
+    if(H5VL_object_get(vol_obj, &loc_params, H5VL_OBJECT_GET_TYPE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, obj_type) < 0)
+        HGOTO_ERROR(H5E_ATOM, H5E_CANTGET, FAIL, "can't retrieve object type")
 
 done:
     FUNC_LEAVE_API(ret_value)
-}   /* end H5Rget_obj_type2() */
+} /* end H5Rget_obj_type3() */
 
 
-/*--------------------------------------------------------------------------
- NAME
-    H5Rget_name
- PURPOSE
-    Determines a name for the object referenced
- USAGE
-    ssize_t H5Rget_name(loc_id, ref_type, ref, name, size)
-        hid_t loc_id;   IN: Dataset reference object is in or location ID of
-                            object that the dataset is located within.
-        H5R_type_t ref_type;    IN: Type of reference
-        void *ref;      IN: Reference to query.
-        char *name;     OUT: Buffer to place name of object referenced. If NULL
-	                     then this call will return the size in bytes of name.
-        size_t size;    IN: Size of name buffer (user needs to include NULL terminator
-                            when passing in the size)
-
- RETURNS
-    Non-negative length of the path on success, -1 on failure
- DESCRIPTION
-    Given a reference to some object, determine a path to the object
-    referenced in the file.
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
-    This may not be the only path to that object.
- EXAMPLES
- REVISION LOG
-    M. Scot Breitenfeld
-    22 January 2014
-    Changed the behavior for the returned value of the function when name is NULL.
-    If name is NULL then size is ignored and the function returns the size 
-    of the name buffer (not including the NULL terminator), it still returns
-    negative on failure.
---------------------------------------------------------------------------*/
+/*-------------------------------------------------------------------------
+ * Function:    H5Rget_file_name
+ *
+ * Purpose: Given a reference to some object, determine a file name of the
+ * object located into.
+ *
+ * Return:  Non-negative length of the path on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
 ssize_t
-H5Rget_name(hid_t id, H5R_type_t ref_type, const void *_ref, char *name,
-    size_t size)
+H5Rget_file_name(const H5R_ref_t *ref_ptr, char *buf, size_t size)
 {
-    H5VL_object_t    *vol_obj = NULL;       /* object token of loc_id */
-    H5VL_loc_params_t loc_params;
-    ssize_t ret_value = -1;             /* Return value */
+    hid_t loc_id;       /* Reference location ID */
+    ssize_t ret_value;  /* Return value */
 
     FUNC_ENTER_API((-1))
-    H5TRACE5("Zs", "iRt*x*sz", id, ref_type, _ref, name, size);
+    H5TRACE3("Zs", "*Rr*sz", ref_ptr, buf, size);
 
     /* Check args */
-    if(ref_type <= H5R_BADTYPE || ref_type >= H5R_MAXTYPE)
+    if(ref_ptr == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, (-1), "invalid reference pointer")
+    if(H5R__get_type((const H5R_ref_priv_t *)ref_ptr) <= H5R_BADTYPE
+        || H5R__get_type((const H5R_ref_priv_t *)ref_ptr) >= H5R_MAXTYPE)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, (-1), "invalid reference type")
-    if(_ref == NULL)
+
+    /* Get name */
+    if(H5I_INVALID_HID == (loc_id = H5R__get_loc_id((const H5R_ref_priv_t *)ref_ptr))) {
+        /* Un-opened external references do not have loc_id set but hold a
+         * copy of the filename */
+        if((ret_value = H5R__get_file_name((const H5R_ref_priv_t *)ref_ptr, buf, size)) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, (-1), "unable to retrieve file name")
+    } else {
+        H5VL_object_t *vol_obj = NULL;  /* Object token of loc_id */
+
+        /* Retrieve VOL file object */
+        if(NULL == (vol_obj = H5VL_vol_object(loc_id)))
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, (-1), "invalid location identifier")
+
+        if(H5VL_file_get(vol_obj, H5VL_FILE_GET_NAME, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5I_FILE, size, buf, &ret_value) < 0)
+                HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, (-1), "unable to get file name")
+    }
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Rget_file_name() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rget_obj_name
+ *
+ * Purpose: Given a reference to some object, determine a path to the object
+ * referenced in the file.
+ *
+ * Return:  Non-negative length of the path on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+ssize_t
+H5Rget_obj_name(const H5R_ref_t *ref_ptr, hid_t rapl_id, char *buf, size_t size)
+{
+    hid_t loc_id;                       /* Reference location ID */
+    H5VL_object_t *vol_obj = NULL;      /* Object token of loc_id */
+    H5VL_loc_params_t loc_params;       /* Location parameters */
+    H5VL_token_t obj_token = {0};       /* Object token */
+    ssize_t ret_value;                  /* Return value */
+
+    FUNC_ENTER_API((-1))
+    H5TRACE4("Zs", "*Rri*sz", ref_ptr, rapl_id, buf, size);
+
+    /* Check args */
+    if(ref_ptr == NULL)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, (-1), "invalid reference pointer")
+    if(H5R__get_type((const H5R_ref_priv_t *)ref_ptr) <= H5R_BADTYPE
+        || H5R__get_type((const H5R_ref_priv_t *)ref_ptr) >= H5R_MAXTYPE)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, (-1), "invalid reference type")
+    if(rapl_id < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a property list")
 
-    /* Set location parameters */
-    loc_params.type = H5VL_OBJECT_BY_SELF;
-    loc_params.obj_type = H5I_get_type(id);
+    /* Retrieve loc_id from reference */
+    if(H5I_INVALID_HID == (loc_id = H5R__get_loc_id((const H5R_ref_priv_t *)ref_ptr))) {
+        /* Attempt to re-open file and pass rapl_id as a fapl_id */
+        if((loc_id = H5R__reopen_file((H5R_ref_priv_t *)ref_ptr, rapl_id)) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENFILE, (-1), "cannot re-open referenced file")
+    }
 
-    /* Get the file object */
-    if(NULL == (vol_obj = (H5VL_object_t *)H5I_object(id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, (-1), "invalid file identifier")
+    /* Get object token */
+    if((ret_value = H5R__get_obj_token((const H5R_ref_priv_t *)ref_ptr, &obj_token, NULL)) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, (-1), "unable to get object token")
 
-    /* Get name */
-    if(H5VL_object_get(vol_obj, &loc_params, H5VL_REF_GET_NAME, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &ret_value, name, size, (int)ref_type, _ref) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, (-1), "unable to determine object path")
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(loc_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, (-1), "invalid location identifier")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_TOKEN;
+    loc_params.loc_data.loc_by_token.token = obj_token;
+    loc_params.obj_type = H5I_get_type(loc_id);
+
+    /* Retrieve object's name */
+    if(H5VL_object_get(vol_obj, &loc_params, H5VL_OBJECT_GET_NAME, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &ret_value, buf, size) < 0)
+        HGOTO_ERROR(H5E_ATOM, H5E_CANTGET, (-1), "can't retrieve object name")
 
 done:
     FUNC_LEAVE_API(ret_value)
-} /* end H5Rget_name() */
+} /* end H5Rget_obj_name() */
 
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rget_attr_name
+ *
+ * Purpose: Given a reference to some attribute, determine its name.
+ *
+ * Return:  Non-negative length of the path on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+ssize_t
+H5Rget_attr_name(const H5R_ref_t *ref_ptr, char *buf, size_t size)
+{
+    ssize_t ret_value;  /* Return value */
+
+    FUNC_ENTER_API((-1))
+    H5TRACE3("Zs", "*Rr*sz", ref_ptr, buf, size);
+
+    /* Check args */
+    if(ref_ptr == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, (-1), "invalid reference pointer")
+    if(H5R__get_type((const H5R_ref_priv_t *)ref_ptr) != H5R_ATTR)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, (-1), "invalid reference type")
+
+    /* Get attribute name */
+    if((ret_value = H5R__get_attr_name((const H5R_ref_priv_t *)ref_ptr, buf, size)) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, (-1), "unable to determine attribute name")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Rget_attr_name() */
diff --git a/src/H5Rdeprec.c b/src/H5Rdeprec.c
index ab8d3b4..4743c77 100644
--- a/src/H5Rdeprec.c
+++ b/src/H5Rdeprec.c
@@ -37,14 +37,15 @@
 #include "H5Ppublic.h"          /* Property lists                           */
 
 /* Private headers needed by this file */
-#include "H5private.h"		/* Generic Functions                        */
-#include "H5ACprivate.h"	/* Metadata cache                           */
+#include "H5private.h"          /* Generic Functions                        */
+#include "H5ACprivate.h"        /* Metadata cache                           */
 #include "H5CXprivate.h"        /* API Contexts                             */
-#include "H5Eprivate.h"		/* Error handling                           */
-#include "H5Gprivate.h"		/* Groups                                   */
+#include "H5Eprivate.h"         /* Error handling                           */
+#include "H5Gprivate.h"         /* Groups                                   */
 #include "H5Iprivate.h"         /* IDs                                      */
-#include "H5Oprivate.h"		/* Object headers                           */
+#include "H5Oprivate.h"         /* Object headers                           */
 #include "H5Rpkg.h"             /* References                               */
+#include "H5Sprivate.h"         /* Dataspaces                               */
 
 
 /****************/
@@ -81,53 +82,61 @@
 /* Local Variables */
 /*******************/
 
-
 #ifndef H5_NO_DEPRECATED_SYMBOLS
-
+
 /*-------------------------------------------------------------------------
  * Function:    H5Rget_obj_type1
  *
- * Purpose:     Retrieves the type of the object that an object points to.
+ * Purpose: Retrieves the type of the object that a reference points to.
  *
- * Parameters:
- *      id          IN: Dataset reference object is in or location ID of
- *                      object that the dataset is located within
- *      ref_type    IN: Type of reference to query
- *      ref         IN: Reference to query
- *
- * Return:      Success:	An object type (as defined in H5Gpublic.h)
- *              Failure:    H5G_UNKNOWN
+ * Return: Object type (as defined in H5Gpublic.h) on success
+ *         H5G_UNKNOWN on failure
  *
  *-------------------------------------------------------------------------
  */
 H5G_obj_t
 H5Rget_obj_type1(hid_t id, H5R_type_t ref_type, const void *ref)
 {
-    H5VL_object_t    *vol_obj = NULL;        /* object token of loc_id */
-    H5VL_loc_params_t loc_params;
-    H5O_type_t obj_type;        /* Object type */
-    H5G_obj_t ret_value;        /* Return value */
+    H5VL_object_t *vol_obj = NULL;      /* Object token of loc_id */
+    H5I_type_t vol_obj_type = H5I_BADID;/* Object type of loc_id */
+    H5VL_loc_params_t loc_params;       /* Location parameters */
+    haddr_t obj_addr;                   /* Object address */
+    H5O_type_t obj_type;                /* Object type */
+    const unsigned char *buf = (const unsigned char *)ref; /* Reference buffer */
+    H5G_obj_t ret_value;                /* Return value */
 
     FUNC_ENTER_API(H5G_UNKNOWN)
     H5TRACE3("Go", "iRt*x", id, ref_type, ref);
 
     /* Check args */
-    if (ref_type <= H5R_BADTYPE || ref_type >= H5R_MAXTYPE)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5G_UNKNOWN, "invalid reference type")
-    if (ref == NULL)
+    if(buf == NULL)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5G_UNKNOWN, "invalid reference pointer")
+    if(ref_type != H5R_OBJECT1 && ref_type != H5R_DATASET_REGION1)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5G_UNKNOWN, "invalid reference type")
 
-    /* Set location parameters */
-    loc_params.type = H5VL_OBJECT_BY_SELF;
-    loc_params.obj_type = H5I_get_type(id);
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5G_UNKNOWN, "invalid location identifier")
 
-    /* Get the vol object */
-    if (NULL == (vol_obj = H5VL_vol_object(id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5G_UNKNOWN, "invalid file identifier")
+    /* Currently restrict API usage to native VOL
+     * TODO check for terminal connector or use capability flag */
 
-    /* Get the object information */
-    if(H5VL_object_get(vol_obj, &loc_params, H5VL_REF_GET_TYPE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &obj_type, (int)ref_type, ref) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, H5G_UNKNOWN, "unable to determine object type")
+    /* Get object type */
+    if((vol_obj_type = H5I_get_type(id)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5G_UNKNOWN, "invalid location identifier")
+
+    /* Get object address */
+    if(H5R__decode_addr_compat(id, vol_obj_type, ref_type, buf, &obj_addr) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, H5G_UNKNOWN, "unable to get object address")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_TOKEN;
+    loc_params.loc_data.loc_by_token.token = &obj_addr;
+    loc_params.obj_type = vol_obj_type;
+
+    /* Retrieve object's type */
+    if(H5VL_object_get(vol_obj, &loc_params, H5VL_OBJECT_GET_TYPE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &obj_type) < 0)
+        HGOTO_ERROR(H5E_ATOM, H5E_CANTGET, H5G_UNKNOWN, "can't retrieve object type")
 
     /* Set return value */
     ret_value = H5G_map_obj_type(obj_type);
@@ -140,54 +149,61 @@ done:
 /*-------------------------------------------------------------------------
  * Function:    H5Rdereference1
  *
- * Purpose:     Opens the HDF5 object referenced.
- *
- * Parameters:
- *      id          IN: Dataset reference object is in or location ID of
- *                      object that the dataset is located within
- *      ref_type    IN: Type of reference to create
- *      ref         IN: Reference to open
+ * Purpose: Given a reference to some object, open that object and return an
+ * ID for that object.
  *
- * Return:      Success:	Valid HDF5 ID
- *              Failure:    H5I_INVALID_HID
+ * Return:  Valid ID on success/Negative on failure
  *
  *-------------------------------------------------------------------------
  */
 hid_t
-H5Rdereference1(hid_t obj_id, H5R_type_t ref_type, const void *_ref)
+H5Rdereference1(hid_t obj_id, H5R_type_t ref_type, const void *ref)
 {
-    H5VL_object_t *vol_obj = NULL;        /* object token of loc_id */
-    H5I_type_t opened_type;
-    void *opened_obj = NULL;
-    H5VL_loc_params_t loc_params;
-    hid_t ret_value = H5I_INVALID_HID;	/* Return value */
+    H5VL_object_t *vol_obj = NULL;      /* Object token of loc_id */
+    H5I_type_t vol_obj_type = H5I_BADID;/* Object type of loc_id */
+    H5VL_loc_params_t loc_params;       /* Location parameters */
+    haddr_t obj_addr;                   /* Object address */
+    H5I_type_t opened_type;             /* Opened object type */
+    void *opened_obj = NULL;            /* Opened object */
+    const unsigned char *buf = (const unsigned char *)ref; /* Reference buffer */
+    hid_t ret_value = H5I_INVALID_HID;  /* Return value */
 
     FUNC_ENTER_API(H5I_INVALID_HID)
-    H5TRACE3("i", "iRt*x", obj_id, ref_type, _ref);
+    H5TRACE3("i", "iRt*x", obj_id, ref_type, ref);
 
     /* Check args */
-    if (ref_type <= H5R_BADTYPE || ref_type >= H5R_MAXTYPE)
-        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference type")
-    if (_ref == NULL)
+    if(buf == NULL)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference pointer")
+    if(ref_type != H5R_OBJECT1 && ref_type != H5R_DATASET_REGION1)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference type")
 
     /* Get the VOL object */
-    if (NULL == (vol_obj = H5VL_vol_object(obj_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid file identifier")
+    if(NULL == (vol_obj = H5VL_vol_object(obj_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
+
+    /* Currently restrict API usage to native VOL
+     * TODO check for terminal connector or use capability flag */
 
-    loc_params.type = H5VL_OBJECT_BY_REF;
-    loc_params.loc_data.loc_by_ref.ref_type = ref_type;
-    loc_params.loc_data.loc_by_ref._ref = _ref;
-    loc_params.loc_data.loc_by_ref.lapl_id = H5P_DATASET_ACCESS_DEFAULT;
-    loc_params.obj_type = H5I_get_type(obj_id);
+    /* Get object type */
+    if((vol_obj_type = H5I_get_type(obj_id)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
+
+    /* Get object address */
+    if(H5R__decode_addr_compat(obj_id, vol_obj_type, ref_type, buf, &obj_addr) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, H5I_INVALID_HID, "unable to get object address")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_TOKEN;
+    loc_params.loc_data.loc_by_token.token = &obj_addr;
+    loc_params.obj_type = vol_obj_type;
 
     /* Dereference */
     if(NULL == (opened_obj = H5VL_object_open(vol_obj, &loc_params, &opened_type, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to dereference object")
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to open object by address")
 
-    /* Get an atom for the object */
+    /* Register object */
     if((ret_value = H5VL_register(opened_type, opened_obj, vol_obj->connector, TRUE)) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to atomize object handle")
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to register object handle")
 
 done:
     FUNC_LEAVE_API(ret_value)
@@ -195,3 +211,363 @@ done:
 
 #endif /* H5_NO_DEPRECATED_SYMBOLS */
 
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rcreate
+ *
+ * Purpose: Creates a particular type of reference specified with REF_TYPE,
+ * in the space pointed to by REF. The LOC_ID and NAME are used to locate the
+ * object pointed to and the SPACE_ID is used to choose the region pointed to
+ * (for Dataset Region references).
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Rcreate(void *ref, hid_t loc_id, const char *name, H5R_type_t ref_type,
+    hid_t space_id)
+{
+    H5VL_object_t *vol_obj = NULL;      /* Object token of loc_id */
+    H5I_type_t vol_obj_type = H5I_BADID;/* Object type of loc_id */
+    H5VL_loc_params_t loc_params;       /* Location parameters */
+    haddr_t obj_addr;                   /* Object address */
+    hid_t file_id = H5I_INVALID_HID;    /* File ID for region reference */
+    unsigned char *buf = (unsigned char *)ref; /* Return reference pointer */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE5("e", "*xi*sRti", ref, loc_id, name, ref_type, space_id);
+
+    /* Check args */
+    if(buf == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference pointer")
+    if(!name || !*name)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no name given")
+    if(ref_type != H5R_OBJECT1 && ref_type != H5R_DATASET_REGION1)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference type")
+
+    /* Set up collective metadata if appropriate */
+    if(H5CX_set_loc(loc_id) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, FAIL, "can't set access property list info")
+
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(loc_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Currently restrict API usage to native VOL
+     * TODO check for terminal connector or use capability flag */
+
+    /* Get object type */
+    if((vol_obj_type = H5I_get_type(loc_id)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_NAME;
+    loc_params.loc_data.loc_by_name.name = name;
+    loc_params.obj_type = vol_obj_type;
+
+    /* Get the object address */
+    if(H5VL_object_specific(vol_obj, &loc_params, H5VL_OBJECT_LOOKUP, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &obj_addr) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, FAIL, "unable to retrieve object address")
+
+    /* Create reference */
+    if(ref_type == H5R_OBJECT1) {
+        size_t buf_size = H5R_OBJ_REF_BUF_SIZE;
+
+        if((ret_value = H5R__encode_addr_obj_compat(obj_addr, buf, &buf_size)) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTENCODE, FAIL, "unable to encode object reference")
+    } else {
+        void *vol_obj_file = NULL;
+        H5F_t *f = NULL;
+        H5S_t *space = NULL; /* Pointer to dataspace containing region */
+        size_t buf_size = H5R_DSET_REG_REF_BUF_SIZE;
+
+        /* Get the file for the object */
+        if((file_id = H5F_get_file_id(loc_id, vol_obj_type, FALSE)) < 0)
+                HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file or file object")
+
+        /* Retrieve VOL object */
+        if(NULL == (vol_obj_file = H5VL_vol_object(file_id)))
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+        /* Retrieve file from VOL object */
+        if(NULL == (f = (H5F_t *)H5VL_object_data(vol_obj_file)))
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid VOL object")
+
+        /* Retrieve space */
+        if(space_id == H5I_BADID)
+            HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "reference region dataspace id must be valid")
+        if(NULL == (space = (struct H5S_t *)H5I_object_verify(space_id, H5I_DATASPACE)))
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataspace")
+
+        /* Encode dataset region */
+        if((ret_value = H5R__encode_addr_region_compat(f, obj_addr, space, buf, &buf_size)) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTENCODE, FAIL, "unable to encode region reference")
+    }
+
+done:
+    if(file_id != H5I_INVALID_HID && H5I_dec_ref(file_id) < 0)
+        HDONE_ERROR(H5E_REFERENCE, H5E_CANTDEC, FAIL, "unable to decrement refcount on file")
+    FUNC_LEAVE_API(ret_value)
+}   /* end H5Rcreate() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rget_obj_type2
+ *
+ * Purpose: Given a reference to some object, this function returns the type
+ * of object pointed to.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Rget_obj_type2(hid_t id, H5R_type_t ref_type, const void *ref,
+    H5O_type_t *obj_type)
+{
+    H5VL_object_t *vol_obj = NULL;      /* Object token of loc_id */
+    H5I_type_t vol_obj_type = H5I_BADID;/* Object type of loc_id */
+    H5VL_loc_params_t loc_params;       /* Location parameters */
+    haddr_t obj_addr;                   /* Object address */
+    const unsigned char *buf = (const unsigned char *)ref; /* Reference pointer */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE4("e", "iRt*x*Ot", id, ref_type, ref, obj_type);
+
+    /* Check args */
+    if(buf == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference pointer")
+    if(ref_type != H5R_OBJECT1 && ref_type != H5R_DATASET_REGION1)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference type")
+
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Currently restrict API usage to native VOL
+     * TODO check for terminal connector or use capability flag */
+
+    /* Get object type */
+    if((vol_obj_type = H5I_get_type(id)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Get object address */
+    if(H5R__decode_addr_compat(id, vol_obj_type, ref_type, buf, &obj_addr) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "unable to get object address")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_TOKEN;
+    loc_params.loc_data.loc_by_token.token = &obj_addr;
+    loc_params.obj_type = vol_obj_type;
+
+    /* Retrieve object's type */
+    if(H5VL_object_get(vol_obj, &loc_params, H5VL_OBJECT_GET_TYPE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, obj_type) < 0)
+        HGOTO_ERROR(H5E_ATOM, H5E_CANTGET, FAIL, "can't retrieve object type")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+}   /* end H5Rget_obj_type2() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rdereference2
+ *
+ * Purpose: Given a reference to some object, open that object and return an
+ * ID for that object.
+ *
+ * Return:  Valid ID on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+hid_t
+H5Rdereference2(hid_t obj_id, hid_t oapl_id, H5R_type_t ref_type,
+    const void *ref)
+{
+    H5VL_object_t *vol_obj = NULL;      /* Object token of loc_id */
+    H5I_type_t vol_obj_type = H5I_BADID;/* Object type of loc_id */
+    H5VL_loc_params_t loc_params;       /* Location parameters */
+    haddr_t obj_addr;                   /* Object address */
+    H5I_type_t opened_type;             /* Opened object type */
+    void *opened_obj = NULL;            /* Opened object */
+    const unsigned char *buf = (const unsigned char *)ref; /* Reference pointer */
+    hid_t ret_value = H5I_INVALID_HID;  /* Return value */
+
+    FUNC_ENTER_API(H5I_INVALID_HID)
+    H5TRACE4("i", "iiRt*x", obj_id, oapl_id, ref_type, ref);
+
+    /* Check args */
+    if(oapl_id < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a property list")
+    if(buf == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference pointer")
+    if(ref_type != H5R_OBJECT1 && ref_type != H5R_DATASET_REGION1)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference type")
+
+    /* Verify access property list and set up collective metadata if appropriate */
+    if(H5CX_set_apl(&oapl_id, H5P_CLS_DACC, obj_id, FALSE) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, H5I_INVALID_HID, "can't set access property list info")
+
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(obj_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid file identifier")
+
+    /* Currently restrict API usage to native VOL
+     * TODO check for terminal connector or use capability flag */
+
+    /* Get object type */
+    if((vol_obj_type = H5I_get_type(obj_id)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
+
+    /* Get object address */
+    if(H5R__decode_addr_compat(obj_id, vol_obj_type, ref_type, buf, &obj_addr) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, H5I_INVALID_HID, "unable to get object address")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_TOKEN;
+    loc_params.loc_data.loc_by_token.token = &obj_addr;
+    loc_params.obj_type = vol_obj_type;
+
+    /* Open object by address */
+    if(NULL == (opened_obj = H5VL_object_open(vol_obj, &loc_params, &opened_type, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to open object by address")
+
+    /* Register object */
+    if((ret_value = H5VL_register(opened_type, opened_obj, vol_obj->connector, TRUE)) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to register object handle")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+}   /* end H5Rdereference2() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rget_region
+ *
+ * Purpose: Given a reference to some object, creates a copy of the dataset
+ * pointed to's dataspace and defines a selection in the copy which is the
+ * region pointed to.
+ *
+ * Return:  Valid ID on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+hid_t
+H5Rget_region(hid_t id, H5R_type_t ref_type, const void *ref)
+{
+    H5VL_object_t *vol_obj = NULL;      /* Object token of loc_id */
+    H5I_type_t vol_obj_type = H5I_BADID;/* Object type of loc_id */
+    void *vol_obj_file = NULL;          /* VOL file */
+    H5F_t *f = NULL;                    /* Native file */
+    size_t buf_size = H5R_DSET_REG_REF_BUF_SIZE;    /* Reference buffer size */
+    H5S_t *space = NULL;                /* Dataspace object */
+    hid_t file_id = H5I_INVALID_HID;    /* File ID for region reference */
+    const unsigned char *buf = (const unsigned char *)ref; /* Reference pointer */
+    hid_t ret_value;                    /* Return value */
+
+    FUNC_ENTER_API(H5I_INVALID_HID)
+    H5TRACE3("i", "iRt*x", id, ref_type, ref);
+
+    /* Check args */
+    if(buf == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference pointer")
+    if(ref_type != H5R_DATASET_REGION1)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "invalid reference type")
+
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid file identifier")
+
+    /* Get object type */
+    if((vol_obj_type = H5I_get_type(id)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
+
+    /* Currently restrict API usage to native VOL
+     * TODO check for terminal connector or use capability flag */
+
+    /* Get the file for the object */
+    if((file_id = H5F_get_file_id(id, vol_obj_type, FALSE)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a file or file object")
+
+    /* Retrieve VOL object */
+    if(NULL == (vol_obj_file = H5VL_vol_object(file_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid location identifier")
+
+    /* Retrieve file from VOL object */
+    if(NULL == (f = (H5F_t *)H5VL_object_data(vol_obj_file)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid VOL object")
+
+    /* Get the dataspace with the correct region selected */
+    if(H5R__decode_addr_region_compat(f, buf, &buf_size, NULL, &space) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, H5I_INVALID_HID, "unable to get dataspace")
+
+    /* Atomize */
+    if((ret_value = H5I_register(H5I_DATASPACE, space, TRUE)) < 0)
+        HGOTO_ERROR(H5E_ATOM, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to register dataspace atom")
+
+done:
+    if(file_id != H5I_INVALID_HID && H5I_dec_ref(file_id) < 0)
+        HDONE_ERROR(H5E_REFERENCE, H5E_CANTDEC, H5I_INVALID_HID, "unable to decrement refcount on file")
+    FUNC_LEAVE_API(ret_value)
+}   /* end H5Rget_region1() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Rget_name
+ *
+ * Purpose: Given a reference to some object, determine a path to the object
+ * referenced in the file.
+ *
+ * Return:  Non-negative length of the path on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+ssize_t
+H5Rget_name(hid_t id, H5R_type_t ref_type, const void *ref, char *name,
+    size_t size)
+{
+    H5VL_object_t *vol_obj = NULL;      /* Object token of loc_id */
+    H5I_type_t vol_obj_type = H5I_BADID;/* Object type of loc_id */
+    H5VL_loc_params_t loc_params;       /* Location parameters */
+    haddr_t obj_addr;                   /* Object address */
+    const unsigned char *buf = (const unsigned char *)ref; /* Reference pointer */
+    ssize_t ret_value = -1;  /* Return value */
+
+    FUNC_ENTER_API((-1))
+    H5TRACE5("Zs", "iRt*x*sz", id, ref_type, ref, name, size);
+
+    /* Check args */
+    if(buf == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, (-1), "invalid reference pointer")
+    if(ref_type != H5R_OBJECT1 && ref_type != H5R_DATASET_REGION1)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, (-1), "invalid reference type")
+
+    /* Get the VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, (-1), "invalid file identifier")
+
+    /* Currently restrict API usage to native VOL
+     * TODO check for terminal connector or use capability flag */
+
+    /* Get object type */
+    if((vol_obj_type = H5I_get_type(id)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, (-1), "invalid location identifier")
+
+    /* Get object address */
+    if(H5R__decode_addr_compat(id, vol_obj_type, ref_type, buf, &obj_addr) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, (-1), "unable to get object address")
+
+    /* Set location parameters */
+    loc_params.type = H5VL_OBJECT_BY_TOKEN;
+    loc_params.loc_data.loc_by_token.token = &obj_addr;
+    loc_params.obj_type = vol_obj_type;
+
+    /* Retrieve object's name */
+    if(H5VL_object_get(vol_obj, &loc_params, H5VL_OBJECT_GET_NAME, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, &ret_value, name, size) < 0)
+        HGOTO_ERROR(H5E_ATOM, H5E_CANTGET, (-1), "can't retrieve object name")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+}   /* end H5Rget_name() */
diff --git a/src/H5Rint.c b/src/H5Rint.c
index 07efae2..e33eecb 100644
--- a/src/H5Rint.c
+++ b/src/H5Rint.c
@@ -35,11 +35,73 @@
 #include "H5Sprivate.h"         /* Dataspaces                               */
 #include "H5Tprivate.h"         /* Datatypes                                */
 
-
 /****************/
 /* Local Macros */
 /****************/
 
+#define H5R_MAX_STRING_LEN  (1 << 16)   /* Max encoded string length    */
+
+/* Encode macro */
+#define H5R_ENCODE(func, val, buf, buf_size, actual, m) do {\
+    size_t __nalloc = buf_size;                             \
+    if(func(val, buf, &__nalloc) < 0)                       \
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTENCODE, FAIL, m) \
+    if(buf && buf_size >= __nalloc) {                       \
+        buf += __nalloc;                                    \
+        buf_size -= __nalloc;                               \
+    }                                                       \
+    actual += __nalloc;                                     \
+} while(0)
+
+#define H5R_ENCODE_VAR(func, var, size, buf, buf_size, actual, m) do {  \
+    size_t __nalloc = buf_size;                                         \
+    if(func(var, size, buf, &__nalloc) < 0)                             \
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTENCODE, FAIL, m)             \
+    if(buf && buf_size >= __nalloc) {                                   \
+        p += __nalloc;                                                  \
+        buf_size -= __nalloc;                                           \
+    }                                                                   \
+    actual += __nalloc;                                                 \
+} while(0)
+
+/* Decode macro */
+#define H5R_DECODE(func, val, buf, buf_size, actual, m) do {\
+    size_t __nbytes = buf_size;                             \
+    if(func(buf, &__nbytes, val) < 0)                       \
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, m) \
+    buf += __nbytes;                                        \
+    buf_size -= __nbytes;                                   \
+    actual += __nbytes;                                     \
+} while(0)
+
+#define H5R_DECODE_VAR(func, var, size, buf, buf_size, actual, m) do {  \
+    size_t __nbytes = buf_size;                                         \
+    if(func(buf, &__nbytes, var, size) < 0)                             \
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, m)             \
+    p += __nbytes;                                                      \
+    buf_size -= __nbytes;                                               \
+    actual += __nbytes;                                                 \
+} while(0)
+
+/* Debug */
+//#define H5R_DEBUG
+#ifdef H5R_DEBUG
+#define H5R_LOG_DEBUG(...) do {                                 \
+      HDfprintf(stdout, " # %s(): ", __func__);                 \
+      HDfprintf(stdout, __VA_ARGS__);                           \
+      HDfprintf(stdout, "\n");                                  \
+      HDfflush(stdout);                                         \
+  } while (0)
+static const char *
+H5R__print_token(const H5VL_token_t token) {
+    static char string[64];
+    HDsnprintf(string, 64, "%zu", *(haddr_t *)token);
+    return string;
+}
+#else
+#define H5R_LOG_DEBUG(...) do { } while (0)
+#endif
+
 /******************/
 /* Local Typedefs */
 /******************/
@@ -48,6 +110,13 @@
 /* Local Prototypes */
 /********************/
 
+static herr_t H5R__encode_obj_token(const H5VL_token_t *obj_token, size_t token_size, unsigned char *buf, size_t *nalloc);
+static herr_t H5R__decode_obj_token(const unsigned char *buf, size_t *nbytes, H5VL_token_t *obj_token, uint8_t *token_size);
+static herr_t H5R__encode_region(H5S_t *space, unsigned char *buf, size_t *nalloc);
+static herr_t H5R__decode_region(const unsigned char *buf, size_t *nbytes, H5S_t **space_ptr);
+static herr_t H5R__encode_string(const char *string, unsigned char *buf, size_t *nalloc);
+static herr_t H5R__decode_string(const unsigned char *buf, size_t *nbytes, char **string_ptr);
+
 /*********************/
 /* Package Variables */
 /*********************/
@@ -82,14 +151,15 @@ DESCRIPTION
 herr_t
 H5R__init_package(void)
 {
-    herr_t ret_value = SUCCEED;         /* Return value */
-
     FUNC_ENTER_NOAPI_NOINIT_NOERR
 
     /* Mark "top" of interface as initialized */
     H5R_top_package_initialize_s = TRUE;
 
-    FUNC_LEAVE_NOAPI(ret_value)
+    /* Sanity check, if assert fails, H5R_REF_BUF_SIZE must be increased */
+    HDcompile_assert(sizeof(H5R_ref_priv_t) <= H5R_REF_BUF_SIZE);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
 } /* end H5R__init_package() */
 
 
@@ -167,571 +237,1473 @@ H5R_term_package(void)
 } /* end H5R_term_package() */
 
 
-/*--------------------------------------------------------------------------
- NAME
-    H5R__create
- PURPOSE
-    Creates a particular kind of reference for the user
- USAGE
-    herr_t H5R__create(ref, loc, name, ref_type, space)
-        void *ref;          OUT: Reference created
-        H5G_loc_t *loc;     IN: File location used to locate object pointed to
-        const char *name;   IN: Name of object at location LOC_ID of object
-                                    pointed to
-        H5R_type_t ref_type;    IN: Type of reference to create
-        H5S_t *space;       IN: Dataspace ID with selection, used for Dataset
-                                    Region references.
+/*-------------------------------------------------------------------------
+ * Function:    H5R__create_object
+ *
+ * Purpose: Creates an object reference.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__create_object(const H5VL_token_t *obj_token, size_t token_size,
+    H5R_ref_priv_t *ref)
+{
+    size_t encode_size;
+    herr_t ret_value = SUCCEED; /* Return value */
 
- RETURNS
-    Non-negative on success/Negative on failure
- DESCRIPTION
-    Creates a particular type of reference specified with REF_TYPE, in the
-    space pointed to by REF.  The LOC_ID and NAME are used to locate the object
-    pointed to and the SPACE_ID is used to choose the region pointed to (for
-    Dataset Region references).
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
- EXAMPLES
- REVISION LOG
---------------------------------------------------------------------------*/
+    FUNC_ENTER_PACKAGE
+
+    HDassert(ref);
+
+    /* Create new reference */
+    H5MM_memcpy(ref->ref.obj.token, obj_token, token_size);
+    ref->ref.obj.filename = NULL;
+    ref->loc_id = H5I_INVALID_HID;
+    ref->type = (uint8_t)H5R_OBJECT2;
+    ref->token_size = (uint8_t)token_size;
+
+    /* Cache encoding size (assume no external reference) */
+    if(H5R__encode(NULL, ref, NULL, &encode_size, 0) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTENCODE, FAIL, "unable to determine encoding size")
+    ref->encode_size = (uint32_t)encode_size;
+
+    H5R_LOG_DEBUG("Created object reference, %d, filename=%s, obj_addr=%s, encode size=%u",
+        (int)sizeof(H5R_ref_priv_t), ref->ref.obj.filename, H5R__print_token(ref->ref.obj.token),
+        ref->encode_size);
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__create_object() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__create_region
+ *
+ * Purpose: Creates a region reference.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
 herr_t
-H5R__create(void *_ref, H5G_loc_t *loc, const char *name, H5R_type_t ref_type, H5S_t *space)
+H5R__create_region(const H5VL_token_t *obj_token, size_t token_size,
+    H5S_t *space, H5R_ref_priv_t *ref)
 {
-    H5G_loc_t	obj_loc;		/* Group hier. location of object */
-    H5G_name_t  path;            	/* Object group hier. path */
-    H5O_loc_t   oloc;            	/* Object object location */
-    hbool_t     obj_found = FALSE;      /* Object location found */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    size_t encode_size;
+    herr_t ret_value = SUCCEED; /* Return value */
 
     FUNC_ENTER_PACKAGE
 
-    HDassert(_ref);
-    HDassert(loc);
-    HDassert(name);
-    HDassert(ref_type > H5R_BADTYPE && ref_type < H5R_MAXTYPE);
+    HDassert(space);
+    HDassert(ref);
 
-    /* Set up object location to fill in */
-    obj_loc.oloc = &oloc;
-    obj_loc.path = &path;
-    H5G_loc_reset(&obj_loc);
+    /* Create new reference */
+    H5MM_memcpy(ref->ref.obj.token, obj_token, token_size);
+    ref->ref.obj.filename = NULL;
+    if(NULL == (ref->ref.reg.space = H5S_copy(space, FALSE, TRUE)))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOPY, FAIL, "unable to copy dataspace")
 
-    /* Set the FAPL for the API context */
-    H5CX_set_libver_bounds(loc->oloc->file);
+    ref->loc_id = H5I_INVALID_HID;
+    ref->type = (uint8_t)H5R_DATASET_REGION2;
+    ref->token_size = (uint8_t)token_size;
 
-    /* Find the object */
-    if(H5G_loc_find(loc, name, &obj_loc) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_NOTFOUND, FAIL, "object not found")
-    obj_found = TRUE;
+    /* Cache encoding size (assume no external reference) */
+    if(H5R__encode(NULL, ref, NULL, &encode_size, 0) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTENCODE, FAIL, "unable to determine encoding size")
+    ref->encode_size = (uint32_t)encode_size;
 
-    switch (ref_type) {
-        case H5R_OBJECT:
-        {
-            hobj_ref_t *ref = (hobj_ref_t *)_ref; /* Get pointer to correct type of reference struct */
+    H5R_LOG_DEBUG("Created region reference, %d, filename=%s, obj_addr=%s, encode size=%u",
+        (int)sizeof(H5R_ref_priv_t), ref->ref.obj.filename, H5R__print_token(ref->ref.obj.token),
+        ref->encode_size);
 
-            *ref = obj_loc.oloc->addr;
-            break;
+done:
+    if(ret_value < 0) {
+        if(ref->ref.reg.space) {
+            H5S_close(ref->ref.reg.space);
+            ref->ref.reg.space = NULL;
         }
+    }
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5R__create_region */
 
-        case H5R_DATASET_REGION:
-        {
-            H5HG_t hobjid;      /* Heap object ID */
-            hdset_reg_ref_t *ref = (hdset_reg_ref_t *)_ref; /* Get pointer to correct type of reference struct */
-            hssize_t buf_size;  /* Size of buffer needed to serialize selection */
-            uint8_t *p;       /* Pointer to OID to store */
-            uint8_t *buf;     /* Buffer to store serialized selection in */
-            unsigned heapid_found;  /* Flag for non-zero heap ID found */
-            unsigned u;        /* local index */
-
-            /* Set up information for dataset region */
-
-            /* Return any previous heap block to the free list if we are
-             * garbage collecting
-             */
-            if (H5F_GC_REF(loc->oloc->file)) {
-                /* Check for an existing heap ID in the reference */
-                for (u = 0, heapid_found = 0, p = (uint8_t *)ref; u < H5R_DSET_REG_REF_BUF_SIZE; u++)
-                    if (p[u] != 0) {
-                        heapid_found = 1;
-                        break;
-                    }
-
-                if (heapid_found != 0) {
-                    /* Return heap block to free list */
-                }
-            }
-
-            /* Zero the heap ID out, may leak heap space if user is re-using
-             * reference and doesn't have garbage collection turned on
-             */
-            HDmemset(ref, 0, H5R_DSET_REG_REF_BUF_SIZE);
-
-            /* Get the amount of space required to serialize the selection */
-            if ((buf_size = H5S_SELECT_SERIAL_SIZE(space)) < 0)
-                HGOTO_ERROR(H5E_REFERENCE, H5E_CANTINIT, FAIL, "Invalid amount of space for serializing selection")
-
-            /* Increase buffer size to allow for the dataset OID */
-            buf_size += (hssize_t)sizeof(haddr_t);
-
-            /* Allocate the space to store the serialized information */
-            H5_CHECK_OVERFLOW(buf_size, hssize_t, size_t);
-            if (NULL == (buf = (uint8_t *)H5MM_malloc((size_t)buf_size)))
-                HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
-
-            /* Serialize information for dataset OID into heap buffer */
-            p = (uint8_t *)buf;
-            H5F_addr_encode(loc->oloc->file, &p, obj_loc.oloc->addr);
-
-            /* Serialize the selection into heap buffer */
-            if (H5S_SELECT_SERIALIZE(space, &p) < 0)
-                HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOPY, FAIL, "Unable to serialize selection")
-
-            /* Save the serialized buffer for later */
-            H5_CHECK_OVERFLOW(buf_size, hssize_t, size_t);
-            if(H5HG_insert(loc->oloc->file, (size_t)buf_size, buf, &hobjid) < 0)
-                HGOTO_ERROR(H5E_REFERENCE, H5E_WRITEERROR, FAIL, "Unable to serialize selection")
-
-            /* Serialize the heap ID and index for storage in the file */
-            p = (uint8_t *)ref;
-            H5F_addr_encode(loc->oloc->file, &p, hobjid.addr);
-            UINT32ENCODE(p, hobjid.idx);
-
-            /* Free the buffer we serialized data in */
-            H5MM_xfree(buf);
-            break;
-        } /* end case H5R_DATASET_REGION */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__create_attr
+ *
+ * Purpose: Creates an attribute reference.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__create_attr(const H5VL_token_t *obj_token, size_t token_size,
+    const char *attr_name, H5R_ref_priv_t *ref)
+{
+    size_t encode_size;
+    herr_t ret_value = SUCCEED; /* Return value */
+
+    FUNC_ENTER_PACKAGE
+
+    HDassert(attr_name);
+    HDassert(ref);
+
+    /* Make sure that attribute name is not longer than supported encode size */
+    if(HDstrlen(attr_name) > H5R_MAX_STRING_LEN)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_ARGS, FAIL, "attribute name too long (%d > %d)", (int)HDstrlen(attr_name), H5R_MAX_STRING_LEN)
+
+    /* Create new reference */
+    H5MM_memcpy(ref->ref.obj.token, obj_token, token_size);
+    ref->ref.obj.filename = NULL;
+    if(NULL == (ref->ref.attr.name = HDstrdup(attr_name)))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOPY, FAIL, "Cannot copy attribute name")
+
+    ref->loc_id = H5I_INVALID_HID;
+    ref->type = (uint8_t)H5R_ATTR;
+    ref->token_size = (uint8_t)token_size;
+
+    /* Cache encoding size (assume no external reference) */
+    if(H5R__encode(NULL, ref, NULL, &encode_size, 0) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTENCODE, FAIL, "unable to determine encoding size")
+    ref->encode_size = (uint32_t)encode_size;
+
+    H5R_LOG_DEBUG("Created attribute reference, %d, filename=%s, obj_addr=%s, attr name=%s, encode size=%u",
+        (int)sizeof(H5R_ref_priv_t), ref->ref.obj.filename, H5R__print_token(ref->ref.obj.token),
+        ref->ref.attr.name, ref->encode_size);
 
+done:
+    if(ret_value < 0)
+        ref->ref.attr.name = H5MM_xfree(ref->ref.attr.name);
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5R__create_attr */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__destroy
+ *
+ * Purpose: Destroy reference.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__destroy(H5R_ref_priv_t *ref)
+{
+    herr_t ret_value = SUCCEED; /* Return value */
+
+    FUNC_ENTER_PACKAGE
+
+    HDassert(ref != NULL);
+
+    ref->ref.obj.filename = H5MM_xfree(ref->ref.obj.filename);
+
+    switch(ref->type) {
+        case H5R_OBJECT2:
+            break;
+        case H5R_DATASET_REGION2:
+            if(H5S_close(ref->ref.reg.space) < 0)
+                HGOTO_ERROR(H5E_REFERENCE, H5E_CANTFREE, FAIL, "Cannot close dataspace")
+            ref->ref.reg.space = NULL;
+            break;
+        case H5R_ATTR:
+            ref->ref.attr.name = H5MM_xfree(ref->ref.attr.name);
+            break;
+        case H5R_OBJECT1:
+        case H5R_DATASET_REGION1:
         case H5R_BADTYPE:
         case H5R_MAXTYPE:
+            HDassert("invalid reference type" && 0);
+            HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, FAIL, "internal error (invalid reference type)")
         default:
             HDassert("unknown reference type" && 0);
             HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, FAIL, "internal error (unknown reference type)")
     } /* end switch */
 
-done:
-    if (obj_found)
-        H5G_loc_free(&obj_loc);
+    /* Decrement refcount of attached loc_id */
+    if((ref->loc_id != H5I_INVALID_HID) && (H5I_dec_ref(ref->loc_id) < 0))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDEC, FAIL, "decrementing location ID failed")
 
+done:
     FUNC_LEAVE_NOAPI(ret_value)
-}   /* end H5R__create() */
+} /* end H5R__destroy() */
 
 
-/*--------------------------------------------------------------------------
- NAME
-    H5R__dereference
- PURPOSE
-    Opens the HDF5 object referenced.
- USAGE
-    hid_t H5R__dereference(ref, oapl_id, ref_type, ref)
-        H5F_t *file;        IN: File the object being dereferenced is within
-        hid_t oapl_id;      IN: Object access property list ID
-        H5R_type_t ref_type; IN: Type of reference
-        void *ref;          IN: Reference to open.
+/*-------------------------------------------------------------------------
+ * Function:    H5R__set_loc_id
+ *
+ * Purpose: Attach location ID to reference and increment location refcount.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__set_loc_id(H5R_ref_priv_t *ref, hid_t id, hbool_t inc_ref)
+{
+    herr_t ret_value = SUCCEED; /* Return value */
 
- RETURNS
-    Valid ID on success, Negative on failure
- DESCRIPTION
-    Given a reference to some object, open that object and return an ID for
-    that object.
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
-    Currently only set up to work with references to datasets
- EXAMPLES
- REVISION LOG
-    Raymond Lu
-    13 July 2011
-    I added the OAPL_ID parameter for the object being referenced.  It only
-    supports dataset access property list currently.
-
-    M. Scot Breitenfeld
-    3 March 2015
-    Added a check for undefined reference pointer.
---------------------------------------------------------------------------*/
+    FUNC_ENTER_PACKAGE
+
+    HDassert(ref != NULL);
+    HDassert(id != H5I_INVALID_HID);
+
+    /* If a location ID was previously assigned, decrement refcount and assign new one */
+    if((ref->loc_id != H5I_INVALID_HID) && (H5I_dec_ref(ref->loc_id) < 0))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDEC, FAIL, "decrementing location ID failed")
+    ref->loc_id = id;
+
+    /* Prevent location ID from being freed until reference is destroyed */
+    if(inc_ref && H5I_inc_ref(ref->loc_id, FALSE) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTINC, FAIL, "incrementing location ID failed")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__set_loc_id() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__get_loc_id
+ *
+ * Purpose: Retrieve location ID attached to existing reference.
+ *
+ * Return:  Valid ID on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
 hid_t
-H5R__dereference(H5F_t *file, hid_t oapl_id, H5R_type_t ref_type, const void *_ref)
+H5R__get_loc_id(const H5R_ref_priv_t *ref)
 {
-    H5O_loc_t oloc;             /* Object location */
-    H5G_name_t path;            /* Path of object */
-    H5G_loc_t loc;              /* Group location */
-    unsigned rc;		/* Reference count of object */
-    H5O_type_t obj_type;        /* Type of object */
     hid_t ret_value = H5I_INVALID_HID;  /* Return value */
 
+    FUNC_ENTER_PACKAGE_NOERR
+
+    HDassert(ref != NULL);
+
+    ret_value = ref->loc_id;
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__get_loc_id() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__reopen_file
+ *
+ * Purpose: Re-open referenced file using file access property list.
+ *
+ * Return:  Valid ID on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+hid_t
+H5R__reopen_file(H5R_ref_priv_t *ref, hid_t fapl_id)
+{
+    void *new_file = NULL;
+    H5VL_connector_prop_t connector_prop;
+    unsigned flags = H5F_ACC_RDWR; /* Must open file read-write to allow for object modifications */
+    H5P_genplist_t *plist;
+    hid_t ret_value = H5I_INVALID_HID;
+
     FUNC_ENTER_PACKAGE
 
-    HDassert(_ref);
-    HDassert(ref_type > H5R_BADTYPE && ref_type < H5R_MAXTYPE);
-    HDassert(file);
+    /* TODO add search path */
 
-    /* Initialize the object location */
-    H5O_loc_reset(&oloc);
-    oloc.file = file;
+    /* Verify access property list and set up collective metadata if appropriate */
+    if(H5CX_set_apl(&fapl_id, H5P_CLS_FACC, H5I_INVALID_HID, TRUE) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, H5I_INVALID_HID, "can't set access property list info")
 
-    switch (ref_type) {
-        case H5R_OBJECT:
-        {
-            oloc.addr = *(const hobj_ref_t *)_ref; /* Only object references currently supported */
-            if (!H5F_addr_defined(oloc.addr) || oloc.addr == 0)
-                HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "Undefined reference pointer")
-            break;
-        }
+    /* Get the VOL info from the fapl */
+    if(NULL == (plist = (H5P_genplist_t *)H5I_object(fapl_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "not a file access property list")
+    if(H5P_peek(plist, H5F_ACS_VOL_CONN_NAME, &connector_prop) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTGET, H5I_INVALID_HID, "can't get VOL connector info")
 
-        case H5R_DATASET_REGION:
-        {
-            H5HG_t hobjid;  /* Heap object ID */
-            uint8_t *buf;   /* Buffer to store serialized selection in */
-            const uint8_t *p;           /* Pointer to OID to store */
+     /* Stash a copy of the "top-level" connector property, before any pass-through
+     *  connectors modify or unwrap it.
+     */
+    if(H5CX_set_vol_connector_prop(&connector_prop) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTSET, H5I_INVALID_HID, "can't set VOL connector info in API context")
 
-            /* Get the heap ID for the dataset region */
-            p = (const uint8_t *)_ref;
-            H5F_addr_decode(oloc.file, &p, &(hobjid.addr));
-            UINT32DECODE(p, hobjid.idx);
+    /* Open the file */
+    if(NULL == (new_file = H5VL_file_open(&connector_prop, H5R_REF_FILENAME(ref), flags, fapl_id, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
+        HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, H5I_INVALID_HID, "unable to open file")
 
-            if (!H5F_addr_defined(hobjid.addr) || hobjid.addr == 0)
-                HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "Undefined reference pointer")
+    /* Get an ID for the file */
+    if((ret_value = H5VL_register_using_vol_id(H5I_FILE, new_file, connector_prop.connector_id, TRUE)) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to atomize file handle")
 
-            /* Get the dataset region from the heap (allocate inside routine) */
-            if(NULL == (buf = (uint8_t *)H5HG_read(oloc.file, &hobjid, NULL, NULL)))
-                HGOTO_ERROR(H5E_REFERENCE, H5E_READERROR, H5I_INVALID_HID, "Unable to read dataset region information")
+    /* Attach loc_id to reference */
+    if(H5R__set_loc_id((H5R_ref_priv_t *)ref, ret_value, FALSE) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, H5I_INVALID_HID, "unable to attach location id to reference")
 
-            /* Get the object oid for the dataset */
-            p = buf;
-            H5F_addr_decode(oloc.file, &p, &(oloc.addr));
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__reopen_file() */
 
-            /* Free the buffer allocated in H5HG_read() */
-            H5MM_xfree(buf);
-            break;
-        } /* end case H5R_DATASET_REGION */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__get_type
+ *
+ * Purpose: Given a reference to some object, return the type of that reference.
+ *
+ * Return:  Type of the reference
+ *
+ *-------------------------------------------------------------------------
+ */
+H5R_type_t
+H5R__get_type(const H5R_ref_priv_t *ref)
+{
+    H5R_type_t ret_value = H5R_BADTYPE;
+
+    FUNC_ENTER_PACKAGE_NOERR
+
+    HDassert(ref != NULL);
+    ret_value = ref->type;
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__get_type() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__equal
+ *
+ * Purpose: Compare two references
+ *
+ * Return:  TRUE if equal, FALSE if unequal, FAIL if error
+ *
+ *-------------------------------------------------------------------------
+ */
+htri_t
+H5R__equal(const H5R_ref_priv_t *ref1, const H5R_ref_priv_t *ref2)
+{
+    htri_t ret_value = TRUE;
+
+    FUNC_ENTER_PACKAGE
 
+    HDassert(ref1 != NULL);
+    HDassert(ref2 != NULL);
+
+    /* Compare reference types */
+    if(ref1->type != ref2->type)
+        HGOTO_DONE(FALSE);
+
+    /* Compare object addresses */
+    if(ref1->token_size != ref2->token_size)
+        HGOTO_DONE(FALSE);
+    if(0 != HDmemcmp(ref1->ref.obj.token, ref2->ref.obj.token, ref1->token_size))
+        HGOTO_DONE(FALSE);
+
+    /* Compare filenames */
+    if((ref1->ref.obj.filename && (NULL == ref2->ref.obj.filename))
+        || ((NULL == ref1->ref.obj.filename) && ref2->ref.obj.filename))
+        HGOTO_DONE(FALSE);
+    if(ref1->ref.obj.filename && ref1->ref.obj.filename
+        && (0 != HDstrcmp(ref1->ref.obj.filename, ref2->ref.obj.filename)))
+        HGOTO_DONE(FALSE);
+
+    switch(ref1->type) {
+        case H5R_OBJECT2:
+            break;
+        case H5R_DATASET_REGION2:
+            if((ret_value = H5S_extent_equal(ref1->ref.reg.space, ref2->ref.reg.space)) < 0)
+                HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOMPARE, FAIL, "cannot compare dataspace extents")
+            break;
+        case H5R_ATTR:
+            HDassert(ref1->ref.attr.name && ref2->ref.attr.name);
+            if(0 != HDstrcmp(ref1->ref.attr.name, ref2->ref.attr.name))
+                HGOTO_DONE(FALSE);
+            break;
+        case H5R_OBJECT1:
+        case H5R_DATASET_REGION1:
         case H5R_BADTYPE:
         case H5R_MAXTYPE:
+            HDassert("invalid reference type" && 0);
+            HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, FAIL, "internal error (invalid reference type)")
         default:
             HDassert("unknown reference type" && 0);
-            HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, H5I_INVALID_HID, "internal error (unknown reference type)")
+            HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, FAIL, "internal error (unknown reference type)")
     } /* end switch */
 
-    /* Get the # of links for object, and its type
-     * (To check to make certain that this object hasn't been deleted
-     *  since the reference was created)
-     */
-    if(H5O_get_rc_and_type(&oloc, &rc, &obj_type) < 0 || 0 == rc)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_LINKCOUNT, H5I_INVALID_HID, "dereferencing deleted object")
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__equal() */
 
-    /* Construct a group location for opening the object */
-    H5G_name_reset(&path);
-    loc.oloc = &oloc;
-    loc.path = &path;
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__copy
+ *
+ * Purpose: Copy a reference
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__copy(const H5R_ref_priv_t *src_ref, H5R_ref_priv_t *dst_ref)
+{
+    herr_t ret_value = SUCCEED;
 
-    /* Open the object */
-    switch (obj_type) {
-        case H5O_TYPE_GROUP:
-        {
-            H5G_t *group;               /* Pointer to group to open */
+    FUNC_ENTER_PACKAGE
 
-            if(NULL == (group = H5G_open(&loc)))
-                HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, H5I_INVALID_HID, "not found")
+    HDassert((src_ref != NULL) && (dst_ref != NULL));
 
-            /* Create an atom for the group */
-            if((ret_value = H5I_register(H5I_GROUP, group, TRUE)) < 0) {
-                H5G_close(group);
-                HGOTO_ERROR(H5E_SYM, H5E_CANTREGISTER, H5I_INVALID_HID, "can't register group")
-            }
+    H5MM_memcpy(dst_ref->ref.obj.token, src_ref->ref.obj.token, src_ref->token_size);
+    dst_ref->encode_size = src_ref->encode_size;
+    dst_ref->type = src_ref->type;
+    dst_ref->token_size = src_ref->token_size;
 
+    switch(src_ref->type) {
+        case H5R_OBJECT2:
             break;
-        }
-
-        case H5O_TYPE_NAMED_DATATYPE:
-        {
-            H5T_t *type;                /* Pointer to datatype to open */
-
-            if(NULL == (type = H5T_open(&loc)))
-                HGOTO_ERROR(H5E_DATATYPE, H5E_NOTFOUND, H5I_INVALID_HID, "not found")
+        case H5R_DATASET_REGION2:
+            if(NULL == (dst_ref->ref.reg.space = H5S_copy(src_ref->ref.reg.space, FALSE, TRUE)))
+                HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOPY, FAIL, "unable to copy dataspace")
+            break;
+        case H5R_ATTR:
+            if(NULL == (dst_ref->ref.attr.name = HDstrdup(src_ref->ref.attr.name)))
+                HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOPY, FAIL, "Cannot copy attribute name")
+            break;
+        case H5R_OBJECT1:
+        case H5R_DATASET_REGION1:
+            HDassert("invalid reference type" && 0);
+            HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, FAIL, "internal error (invalid reference type)")
+        case H5R_BADTYPE:
+        case H5R_MAXTYPE:
+        default:
+            HDassert("unknown reference type" && 0);
+            HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, FAIL, "internal error (unknown reference type)")
+    } /* end switch */
 
-            /* Create an atom for the datatype */
-            if((ret_value = H5I_register(H5I_DATATYPE, type, TRUE)) < 0) {
-                H5T_close(type);
-                HGOTO_ERROR(H5E_DATATYPE, H5E_CANTREGISTER, H5I_INVALID_HID, "can't register datatype")
-            }
+    /* We only need to keep a copy of the filename if we don't have the loc_id */
+    if(src_ref->loc_id == H5I_INVALID_HID) {
+        HDassert(src_ref->ref.obj.filename);
 
-            break;
-        }
+        if(NULL == (dst_ref->ref.obj.filename = HDstrdup(src_ref->ref.obj.filename)))
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOPY, FAIL, "Cannot copy filename")
+        dst_ref->loc_id = H5I_INVALID_HID;
+    } else {
+        dst_ref->ref.obj.filename = NULL;
 
-        case H5O_TYPE_DATASET:
-        {
-            H5D_t *dset;                /* Pointer to dataset to open */
+        /* Set location ID and hold reference to it */
+        if(H5R__set_loc_id(dst_ref, src_ref->loc_id, TRUE) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, FAIL, "cannot set reference location ID")
+    }
 
-            /* Open the dataset */
-            if(NULL == (dset = H5D_open(&loc, oapl_id)))
-                HGOTO_ERROR(H5E_DATASET, H5E_NOTFOUND, H5I_INVALID_HID, "not found")
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__copy() */
 
-            /* Create an atom for the dataset */
-            if((ret_value = H5I_register(H5I_DATASET, dset, TRUE)) < 0) {
-                H5D_close(dset);
-                HGOTO_ERROR(H5E_DATASET, H5E_CANTREGISTER, H5I_INVALID_HID, "can't register dataset")
-            }
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__get_obj_token
+ *
+ * Purpose: Given a reference to some object, get the encoded object addr.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__get_obj_token(const H5R_ref_priv_t *ref, H5VL_token_t *obj_token,
+    size_t *token_size)
+{
+    herr_t ret_value = SUCCEED; /* Return value */
 
-            break;
-        }
+    FUNC_ENTER_PACKAGE
 
-        case H5O_TYPE_MAP:
-            HGOTO_ERROR(H5E_REFERENCE, H5E_BADTYPE, H5I_INVALID_HID, "maps not supported in native VOL connector")
+    HDassert(ref != NULL);
+    HDassert(ref->token_size <= H5VL_MAX_TOKEN_SIZE);
 
-        case H5O_TYPE_UNKNOWN:
-        case H5O_TYPE_NTYPES:
-        default:
-            HGOTO_ERROR(H5E_REFERENCE, H5E_BADTYPE, H5I_INVALID_HID, "can't identify type of object referenced")
-     } /* end switch */
+    if(obj_token) {
+        if(0 == ref->token_size)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOPY, FAIL, "NULL token size")
+        H5MM_memcpy(obj_token, ref->ref.obj.token, ref->token_size);
+    }
+    if(token_size)
+        *token_size = ref->token_size;
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-}   /* end H5R__dereference() */
+} /* end H5R__get_obj_token() */
 
 
-/*--------------------------------------------------------------------------
- NAME
-    H5R__get_region
- PURPOSE
-    Retrieves a dataspace with the region pointed to selected.
- USAGE
-    H5S_t *H5R__get_region(file, ref)
-        H5F_t *file;        IN: File the object being dereferenced is within
-        void *ref;          IN: Reference to open.
+/*-------------------------------------------------------------------------
+ * Function:    H5R__set_obj_token
+ *
+ * Purpose: Given a reference to some object, set the encoded object addr.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__set_obj_token(H5R_ref_priv_t *ref, const H5VL_token_t *obj_token,
+    size_t token_size)
+{
+    herr_t ret_value = SUCCEED; /* Return value */
 
- RETURNS
-    Pointer to the dataspace on success, NULL on failure
- DESCRIPTION
-    Given a reference to some object, creates a copy of the dataset pointed
-    to's dataspace and defines a selection in the copy which is the region
-    pointed to.
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
- EXAMPLES
- REVISION LOG
---------------------------------------------------------------------------*/
-H5S_t *
-H5R__get_region(H5F_t *file, const void *_ref)
+    FUNC_ENTER_PACKAGE_NOERR
+
+    HDassert(ref != NULL);
+    HDassert(obj_token);
+    HDassert(token_size);
+    HDassert(token_size <= H5VL_MAX_TOKEN_SIZE);
+
+    H5MM_memcpy(ref->ref.obj.token, obj_token, ref->token_size);
+    ref->token_size = token_size;
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__set_obj_token() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__get_region
+ *
+ * Purpose: Given a reference to some object, creates a copy of the dataset
+ * pointed to's dataspace and defines a selection in the copy which is the
+ * region pointed to.
+ *
+ * Return:  Pointer to the dataspace on success/NULL on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__get_region(const H5R_ref_priv_t *ref, H5S_t *space)
 {
-    H5O_loc_t oloc;             /* Object location */
-    const uint8_t *p;           /* Pointer to OID to store */
-    H5HG_t hobjid;              /* Heap object ID */
-    uint8_t *buf = NULL;        /* Buffer to store serialized selection in */
-    H5S_t *ret_value;           /* Return value */
+    herr_t ret_value = SUCCEED; /* Return value */
 
     FUNC_ENTER_PACKAGE
 
-    HDassert(_ref);
-    HDassert(file);
+    HDassert(ref != NULL);
+    HDassert(ref->type == H5R_DATASET_REGION2);
+    HDassert(space);
 
-    /* Initialize the object location */
-    H5O_loc_reset(&oloc);
-    oloc.file = file;
+    /* Copy reference selection to destination */
+    if(H5S_select_copy(space, ref->ref.reg.space, FALSE) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOPY, FAIL, "unable to copy selection")
 
-    /* Get the heap ID for the dataset region */
-    p = (const uint8_t *)_ref;
-    H5F_addr_decode(oloc.file, &p, &(hobjid.addr));
-    UINT32DECODE(p, hobjid.idx);
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__get_region() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__get_file_name
+ *
+ * Purpose: Given a reference to some object, determine a file name of the
+ * object located into.
+ *
+ * Return:  Non-negative length of the path on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+ssize_t
+H5R__get_file_name(const H5R_ref_priv_t *ref, char *buf, size_t size)
+{
+    size_t copy_len;
+    ssize_t ret_value = -1;     /* Return value */
 
-    /* Get the dataset region from the heap (allocate inside routine) */
-    if(NULL == (buf = (uint8_t *)H5HG_read(oloc.file, &hobjid, NULL, NULL)))
-        HGOTO_ERROR(H5E_REFERENCE, H5E_READERROR, NULL, "Unable to read dataset region information")
+    FUNC_ENTER_PACKAGE
 
-    /* Get the object oid for the dataset */
-    p = buf;
-    H5F_addr_decode(oloc.file, &p, &(oloc.addr));
+    /* Check args */
+    HDassert(ref != NULL);
 
-    /* Open and copy the dataset's dataspace */
-    if(NULL == (ret_value = H5S_read(&oloc)))
-        HGOTO_ERROR(H5E_DATASPACE, H5E_NOTFOUND, NULL, "not found")
+    /* Return if that reference has no filename set */
+    if(!ref->ref.obj.filename)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_ARGS, (-1), "no filename available for that reference")
 
-    /* Unserialize the selection */
-    if(H5S_SELECT_DESERIALIZE(&ret_value, &p) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, NULL, "can't deserialize selection")
+    /* Get the file name length */
+    copy_len = HDstrlen(ref->ref.obj.filename);
+    HDassert(copy_len <= H5R_MAX_STRING_LEN);
 
-done:
-    /* Free the buffer allocated in H5HG_read() */
-    if(buf)
-        H5MM_xfree(buf);
+    /* Copy the file name */
+    if(buf) {
+        copy_len = MIN(copy_len, size - 1);
+        H5MM_memcpy(buf, ref->ref.obj.filename, copy_len);
+        buf[copy_len] = '\0';
+    }
+    ret_value = (ssize_t)(copy_len + 1);
 
+done:
     FUNC_LEAVE_NOAPI(ret_value)
-}   /* end H5R__get_region() */
+} /* end H5R__get_file_name() */
 
 
-/*--------------------------------------------------------------------------
- NAME
-    H5R__get_obj_type
- PURPOSE
-    Retrieves the type of object that an object reference points to
- USAGE
-    H5O_type_t H5R__get_obj_type(file, ref_type, ref)
-        H5F_t *file;        IN: File the object being dereferenced is within
-        H5R_type_t ref_type;    IN: Type of reference to query
-        void *ref;          IN: Reference to query.
-        H5O_type_t *obj_type;	OUT: The type of the object, set on success
+/*-------------------------------------------------------------------------
+ * Function:    H5R__get_attr_name
+ *
+ * Purpose: Given a reference to some attribute, determine its name.
+ *
+ * Return:  Non-negative length of the path on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+ssize_t
+H5R__get_attr_name(const H5R_ref_priv_t *ref, char *buf, size_t size)
+{
+    ssize_t ret_value = -1;     /* Return value */
+    size_t attr_name_len;       /* Length of the attribute name */
 
- RETURNS
-    Non-negative on success/Negative on failure
- DESCRIPTION
-    Given a reference to some object, this function returns the type of object
-    pointed to.
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
- EXAMPLES
- REVISION LOG
---------------------------------------------------------------------------*/
+    FUNC_ENTER_PACKAGE_NOERR
+
+    /* Check args */
+    HDassert(ref != NULL);
+    HDassert(ref->type == H5R_ATTR);
+
+    /* Get the attribute name length */
+    attr_name_len = HDstrlen(ref->ref.attr.name);
+    HDassert(attr_name_len <= H5R_MAX_STRING_LEN);
+
+    /* Get the attribute name */
+    if(buf) {
+        size_t copy_len = MIN(attr_name_len, size - 1);
+        H5MM_memcpy(buf, ref->ref.attr.name, copy_len);
+        buf[copy_len] = '\0';
+    }
+
+    ret_value = (ssize_t)(attr_name_len + 1);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__get_attr_name() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__encode
+ *
+ * Purpose: Private function for H5Rencode.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
 herr_t
-H5R__get_obj_type(H5F_t *file, H5R_type_t ref_type, const void *_ref,
-    H5O_type_t *obj_type)
+H5R__encode(const char *filename, const H5R_ref_priv_t *ref, unsigned char *buf,
+    size_t *nalloc, unsigned flags)
 {
-    H5O_loc_t oloc;             /* Object location */
-    unsigned rc;		/* Reference count of object    */
-    herr_t ret_value = SUCCEED; /* Return value */
+    uint8_t *p = (uint8_t *)buf;
+    size_t buf_size = 0, encode_size = 0;
+    herr_t ret_value = SUCCEED;
 
     FUNC_ENTER_PACKAGE
 
-    HDassert(file);
-    HDassert(_ref);
+    HDassert(ref);
+    HDassert(nalloc);
+
+    /**
+     * Encoding format:
+     * | Reference type (8 bits) | Flags (8 bits) | Token (token size)
+     *    |                         |
+     *    |                         |----> H5R_IS_EXTERNAL: File info
+     *    |
+     *    |----> H5R_DATASET_REGION2: Serialized selection
+     *    |
+     *    |----> H5R_ATTR: Attribute name len + name
+     *
+     */
+
+    /* Don't encode if buffer size isn't big enough or buffer is empty */
+    if(buf && *nalloc >= H5R_ENCODE_HEADER_SIZE) {
+        /* Encode the type of the reference */
+        *p++ = (uint8_t)ref->type;
+
+        /* Encode the flags */
+        *p++ = (uint8_t)flags;
 
-    /* Initialize the symbol table entry */
-    H5O_loc_reset(&oloc);
-    oloc.file = file;
+        buf_size = *nalloc - H5R_ENCODE_HEADER_SIZE;
+    }
+    encode_size += H5R_ENCODE_HEADER_SIZE;
+
+    /* Encode object token */
+    H5R_ENCODE_VAR(H5R__encode_obj_token, &ref->ref.obj.token, ref->token_size,
+        p, buf_size, encode_size, "Cannot encode object address");
+
+    /**
+     * TODO Encode VOL info
+     * When we have a better way of storing blobs, we should add
+     * support for referencing files in external VOLs.
+     * There are currently multiple limitations:
+     *   - avoid duplicating VOL info on each reference
+     *   - must query terminal VOL connector to avoid passthrough confusion
+     */
+    if(flags & H5R_IS_EXTERNAL) {
+        /* Encode file name */
+        H5R_ENCODE(H5R__encode_string, filename, p, buf_size, encode_size,
+            "Cannot encode filename");
+    }
 
-    switch (ref_type) {
-        case H5R_OBJECT:
-        {
-            /* Get the object oid */
-            oloc.addr = *(const hobj_ref_t *)_ref; /* Only object references currently supported */
+    switch(ref->type) {
+        case H5R_OBJECT2:
             break;
-        }
+        case H5R_DATASET_REGION2:
+            /* Encode dataspace */
+            H5R_ENCODE(H5R__encode_region, ref->ref.reg.space, p, buf_size,
+                encode_size, "Cannot encode region");
+            break;
+        case H5R_ATTR:
+            /* Encode attribute name */
+            H5R_ENCODE(H5R__encode_string, ref->ref.attr.name, p, buf_size,
+                encode_size, "Cannot encode attribute name");
+            break;
+        case H5R_OBJECT1:
+        case H5R_DATASET_REGION1:
+        case H5R_BADTYPE:
+        case H5R_MAXTYPE:
+            HDassert("invalid reference type" && 0);
+            HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, FAIL, "internal error (invalid reference type)")
+        default:
+            HDassert("unknown reference type" && 0);
+            HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, FAIL, "internal error (unknown reference type)")
+    } /* end switch */
+
+    *nalloc = encode_size;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__encode() */
 
-        case H5R_DATASET_REGION:
-        {
-            H5HG_t hobjid;      /* Heap object ID */
-            const uint8_t *p;   /* Pointer to reference to decode */
-            uint8_t *buf;       /* Buffer to store serialized selection in */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__decode
+ *
+ * Purpose: Private function for H5Rdecode.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__decode(const unsigned char *buf, size_t *nbytes, H5R_ref_priv_t *ref)
+{
+    const uint8_t *p = (const uint8_t *)buf;
+    size_t buf_size = 0, decode_size = 0;
+    uint8_t flags;
+    herr_t ret_value = SUCCEED;
 
-            /* Get the heap ID for the dataset region */
-            p = (const uint8_t *)_ref;
-            H5F_addr_decode(oloc.file, &p, &(hobjid.addr));
-            UINT32DECODE(p, hobjid.idx);
+    FUNC_ENTER_PACKAGE
 
-            /* Get the dataset region from the heap (allocate inside routine) */
-            if(NULL == (buf = (uint8_t *)H5HG_read(oloc.file, &hobjid, NULL, NULL)))
-                HGOTO_ERROR(H5E_REFERENCE, H5E_READERROR, FAIL, "Unable to read dataset region information")
+    HDassert(buf);
+    HDassert(nbytes);
+    HDassert(ref);
+    buf_size = *nbytes;
 
-            /* Get the object oid for the dataset */
-            p = buf;
-            H5F_addr_decode(oloc.file, &p, &(oloc.addr));
+    /* Don't decode if buffer size isn't big enough */
+    if(buf_size < H5R_ENCODE_HEADER_SIZE)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Buffer size is too small")
 
-            /* Free the buffer allocated in H5HG_read() */
-            H5MM_xfree(buf);
+    /* Set new reference */
+    ref->type = (H5R_type_t)*p++;
+    if(ref->type <= H5R_BADTYPE || ref->type >= H5R_MAXTYPE)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference type")
 
-            break;
-        }
+    /* Set flags */
+    flags = *p++;
+
+    buf_size -= H5R_ENCODE_HEADER_SIZE;
+    decode_size += H5R_ENCODE_HEADER_SIZE;
 
+    /* Decode object token */
+    H5R_DECODE_VAR(H5R__decode_obj_token, &ref->ref.obj.token, &ref->token_size,
+        p, buf_size, decode_size, "Cannot decode object address");
+
+    /* We do not need to store the filename if the reference is internal */
+    if(flags & H5R_IS_EXTERNAL) {
+        /* Decode file name */
+        H5R_DECODE(H5R__decode_string, &ref->ref.obj.filename, p, buf_size,
+            decode_size, "Cannot decode filename");
+    } else
+        ref->ref.obj.filename = NULL;
+
+    switch(ref->type) {
+        case H5R_OBJECT2:
+            break;
+        case H5R_DATASET_REGION2:
+            /* Decode dataspace */
+            H5R_DECODE(H5R__decode_region, &ref->ref.reg.space, p, buf_size,
+                decode_size, "Cannot decode region");
+            break;
+        case H5R_ATTR:
+            /* Decode attribute name */
+            H5R_DECODE(H5R__decode_string, &ref->ref.attr.name, p, buf_size,
+                decode_size, "Cannot decode attribute name");
+            break;
+        case H5R_OBJECT1:
+        case H5R_DATASET_REGION1:
         case H5R_BADTYPE:
         case H5R_MAXTYPE:
+            HDassert("invalid reference type" && 0);
+            HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, FAIL, "internal error (invalid reference type)")
         default:
             HDassert("unknown reference type" && 0);
             HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, FAIL, "internal error (unknown reference type)")
     } /* end switch */
 
-    /* Get the # of links for object, and its type */
-    /* (To check to make certain that this object hasn't been deleted since the reference was created) */
-    if(H5O_get_rc_and_type(&oloc, &rc, obj_type) < 0 || 0 == rc)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_LINKCOUNT, FAIL, "dereferencing deleted object")
+    /* Set loc ID to invalid */
+    ref->loc_id = H5I_INVALID_HID;
+
+    /* Set encoding size */
+    ref->encode_size = decode_size;
+
+    H5R_LOG_DEBUG("Decoded reference, filename=%s, obj_addr=%s, encode size=%u",
+        ref->ref.obj.filename, H5R__print_token(ref->ref.obj.token),
+        ref->encode_size);
+
+    *nbytes = decode_size;
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-}   /* end H5R__get_obj_type() */
+} /* end H5R__decode() */
 
 
-/*--------------------------------------------------------------------------
- NAME
-    H5R__get_name
- PURPOSE
-    Internal routine to determine a name for the object referenced
- USAGE
-    ssize_t H5R__get_name(f, ref_type, ref, name, size)
-        H5F_t *f;       IN: Pointer to the file that the reference is pointing
-                            into
-        hid_t lapl_id;  IN: LAPL to use for operation
-        hid_t id;       IN: Location ID given for reference
-        H5R_type_t ref_type;    IN: Type of reference
-        void *_ref;     IN: Reference to query.
-        char *name;     OUT: Buffer to place name of object referenced
-        size_t size;    IN: Size of name buffer
+/*-------------------------------------------------------------------------
+ * Function:    H5R__encode_obj_token
+ *
+ * Purpose: Encode an object address.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5R__encode_obj_token(const H5VL_token_t *obj_token, size_t token_size,
+    unsigned char *buf, size_t *nalloc)
+{
+    herr_t ret_value = SUCCEED;
 
- RETURNS
-    Non-negative length of the path on success, -1 on failure
- DESCRIPTION
-    Given a reference to some object, determine a path to the object
-    referenced in the file.
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
-    This may not be the only path to that object.
- EXAMPLES
- REVISION LOG
---------------------------------------------------------------------------*/
-ssize_t
-H5R__get_name(H5F_t *f, H5R_type_t ref_type, const void *_ref,
-    char *name, size_t size)
+    FUNC_ENTER_STATIC_NOERR
+
+    HDassert(nalloc);
+
+    /* Don't encode if buffer size isn't big enough or buffer is empty */
+    if(buf && *nalloc >= token_size) {
+        uint8_t *p = (uint8_t *)buf;
+
+        /* Encode token size */
+        *p++ = (uint8_t)(token_size & 0xff);
+
+        /* Encode token */
+        H5MM_memcpy(p, obj_token, token_size);
+    }
+    *nalloc = token_size + H5_SIZEOF_UINT8_T;
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__encode_obj_token() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__decode_obj_token
+ *
+ * Purpose: Decode an object address.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5R__decode_obj_token(const unsigned char *buf, size_t *nbytes,
+    H5VL_token_t *obj_token, uint8_t *token_size)
 {
-    H5O_loc_t oloc;             /* Object location describing object for reference */
-    ssize_t ret_value = -1;     /* Return value */
+    const uint8_t *p = (const uint8_t *)buf;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(buf);
+    HDassert(nbytes);
+    HDassert(obj_token);
+    HDassert(token_size);
+
+    /* Don't decode if buffer size isn't big enough */
+    if(*nbytes < H5_SIZEOF_UINT8_T)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Buffer size is too small")
+
+    /* Get token size */
+    *token_size = *p++;
+    if(*token_size > sizeof(H5VL_token_t))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Invalid token size (%u)", *token_size)
+
+    /* Decode token */
+    H5MM_memcpy(obj_token, p, *token_size);
+
+    *nbytes = *token_size + H5_SIZEOF_UINT8_T;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__decode_obj_token() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__encode_region
+ *
+ * Purpose: Encode a selection.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5R__encode_region(H5S_t *space, unsigned char *buf, size_t *nalloc)
+{
+    uint8_t *p = NULL; /* Pointer to data to store */
+    hssize_t buf_size = 0;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(space);
+    HDassert(nalloc);
+
+    /* Get the amount of space required to serialize the selection */
+    if((buf_size = H5S_SELECT_SERIAL_SIZE(space)) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTENCODE, FAIL, "Cannot determine amount of space needed for serializing selection")
+
+    /* Don't encode if buffer size isn't big enough or buffer is empty */
+    if(buf && *nalloc >= ((size_t)buf_size + 2 * H5_SIZEOF_UINT32_T)) {
+        p = (uint8_t *)buf;
+        int rank;
+
+        /* Encode the size for safety check */
+        UINT32ENCODE(p, (uint32_t)buf_size);
+
+        /* Encode the extent rank */
+        if((rank = H5S_get_simple_extent_ndims(space)) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, FAIL, "can't get extent rank for selection")
+        UINT32ENCODE(p, (uint32_t)rank);
+
+        /* Serialize the selection */
+        if(H5S_SELECT_SERIALIZE(space, (unsigned char **)&p) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTENCODE, FAIL, "can't serialize selection")
+    }
+    *nalloc = (size_t)buf_size + 2 * H5_SIZEOF_UINT32_T;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__encode_region() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__decode_region
+ *
+ * Purpose: Decode a selection.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5R__decode_region(const unsigned char *buf, size_t *nbytes, H5S_t **space_ptr)
+{
+    const uint8_t *p = (const uint8_t *)buf;
+    size_t buf_size = 0;
+    unsigned rank;
+    H5S_t *space;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(buf);
+    HDassert(nbytes);
+    HDassert(space_ptr);
+
+    /* Don't decode if buffer size isn't big enough */
+    if(*nbytes < (2 * H5_SIZEOF_UINT32_T))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Buffer size is too small")
+
+    /* Decode the selection size */
+    UINT32DECODE(p, buf_size);
+    buf_size += H5_SIZEOF_UINT32_T;
+
+    /* Decode the extent rank */
+    UINT32DECODE(p, rank);
+    buf_size += H5_SIZEOF_UINT32_T;
+
+    /* Don't decode if buffer size isn't big enough */
+    if(*nbytes < buf_size)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Buffer size is too small")
+
+    /* Deserialize the selection (dataspaces need the extent rank information) */
+    if(NULL == (space = H5S_create(H5S_SIMPLE)))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Buffer size is too small")
+    if(H5S_set_extent_simple(space, rank, NULL, NULL) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, FAIL, "can't set extent rank for selection")
+    if(H5S_SELECT_DESERIALIZE(&space, &p) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "can't deserialize selection")
+
+    *nbytes = buf_size;
+    *space_ptr = space;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__decode_region() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__encode_string
+ *
+ * Purpose: Encode a string.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5R__encode_string(const char *string, unsigned char *buf, size_t *nalloc)
+{
+    size_t string_len, buf_size;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(string);
+    HDassert(nalloc);
+
+    /* Get the amount of space required to serialize the string */
+    string_len = HDstrlen(string);
+    if(string_len > H5R_MAX_STRING_LEN)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_ARGS, FAIL, "string too long")
+
+    /* Compute buffer size, allow for the attribute name length and object address */
+    buf_size = string_len + sizeof(uint16_t);
+
+    if(buf && *nalloc >= buf_size) {
+        uint8_t *p = (uint8_t *)buf;
+        /* Serialize information for string length into the buffer */
+        UINT16ENCODE(p, string_len);
+        /* Copy the string into the buffer */
+        H5MM_memcpy(p, string, string_len);
+    }
+    *nalloc = buf_size;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__encode_string() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__decode_string
+ *
+ * Purpose: Decode a string.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5R__decode_string(const unsigned char *buf, size_t *nbytes, char **string_ptr)
+{
+    const uint8_t *p = (const uint8_t *)buf;
+    size_t string_len;
+    char *string = NULL;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(buf);
+    HDassert(nbytes);
+    HDassert(string_ptr);
+
+    /* Don't decode if buffer size isn't big enough */
+    if(*nbytes < sizeof(uint16_t))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Buffer size is too small")
+
+    /* Get the string length */
+    UINT16DECODE(p, string_len);
+    HDassert(string_len <= H5R_MAX_STRING_LEN);
+
+    /* Allocate the string */
+    if(NULL == (string = H5MM_malloc(string_len + 1)))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTALLOC, FAIL, "Cannot allocate string")
+
+     /* Copy the string */
+     H5MM_memcpy(string, p, string_len);
+     string[string_len] = '\0';
+
+     *string_ptr = string;
+     *nbytes = sizeof(uint16_t) + string_len;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__decode_string() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__encode_heap
+ *
+ * Purpose: Encode data and insert into heap (native only).
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__encode_heap(H5F_t *f, unsigned char *buf, size_t *nalloc,
+    const unsigned char *data, size_t data_size)
+{
+    size_t buf_size;
+    herr_t ret_value = SUCCEED;
 
     FUNC_ENTER_PACKAGE
 
-    /* Check args */
     HDassert(f);
-    HDassert(_ref);
+    HDassert(nalloc);
 
-    /* Initialize the object location */
-    H5O_loc_reset(&oloc);
-    oloc.file = f;
+    buf_size = H5HG_HEAP_ID_SIZE(f);
+    if(buf && *nalloc >= buf_size) {
+        H5HG_t hobjid;
+        uint8_t *p = (uint8_t *)buf;
 
-    /* Get address for reference */
-    switch (ref_type) {
-        case H5R_OBJECT:
-        {
-            oloc.addr = *(const hobj_ref_t *)_ref;
-            break;
-        }
+        /* Write the reference information to disk (allocates space also) */
+        if(H5HG_insert(f, data_size, (void *)data, &hobjid) < 0)
+            HGOTO_ERROR(H5E_DATATYPE, H5E_WRITEERROR, FAIL, "Unable to write reference information")
 
-        case H5R_DATASET_REGION:
-        {
-            H5HG_t hobjid;  /* Heap object ID */
-            uint8_t *buf;   /* Buffer to store serialized selection in */
-            const uint8_t *p;           /* Pointer to OID to store */
+        /* Encode the heap information */
+        H5F_addr_encode(f, &p, hobjid.addr);
+        UINT32ENCODE(p, hobjid.idx);
+    }
+    *nalloc = buf_size;
 
-            /* Get the heap ID for the dataset region */
-            p = (const uint8_t *)_ref;
-            H5F_addr_decode(oloc.file, &p, &(hobjid.addr));
-            UINT32DECODE(p, hobjid.idx);
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__encode_heap() */
 
-            /* Get the dataset region from the heap (allocate inside routine) */
-            if((buf = (uint8_t *)H5HG_read(oloc.file, &hobjid, NULL, NULL)) == NULL)
-                HGOTO_ERROR(H5E_REFERENCE, H5E_READERROR, (-1), "Unable to read dataset region information")
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__decode_heap
+ *
+ * Purpose: Decode data inserted into heap (native only).
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__decode_heap(H5F_t *f, const unsigned char *buf, size_t *nbytes,
+    unsigned char **data_ptr, size_t *data_size)
+{
+    const uint8_t *p = (const uint8_t *)buf;
+    H5HG_t hobjid;
+    size_t buf_size;
+    herr_t ret_value = SUCCEED;
 
-            /* Get the object oid for the dataset */
-            p = buf;
-            H5F_addr_decode(oloc.file, &p, &(oloc.addr));
+    FUNC_ENTER_PACKAGE
 
-            /* Free the buffer allocated in H5HG_read() */
-            H5MM_xfree(buf);
+    HDassert(f);
+    HDassert(buf);
+    HDassert(nbytes);
+    HDassert(data_ptr);
+
+    buf_size = H5HG_HEAP_ID_SIZE(f);
+    /* Don't decode if buffer size isn't big enough */
+    if(*nbytes < buf_size)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Buffer size is too small")
+
+    /* Get the heap information */
+    H5F_addr_decode(f, &p, &(hobjid.addr));
+    if(!H5F_addr_defined(hobjid.addr) || hobjid.addr == 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "Undefined reference pointer")
+    UINT32DECODE(p, hobjid.idx);
 
-            break;
-        }
+    /* Read the information from disk */
+    if(NULL == (*data_ptr = (unsigned char *)H5HG_read(f, &hobjid, (void *)*data_ptr, data_size)))
+        HGOTO_ERROR(H5E_DATATYPE, H5E_READERROR, FAIL, "Unable to read reference data")
 
-        case H5R_BADTYPE:
-        case H5R_MAXTYPE:
-        default:
-            HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, (-1), "internal error (unknown reference type)")
-    } /* end switch */
+    *nbytes = buf_size;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__decode_heap() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__free_heap
+ *
+ * Purpose: Remove data previously inserted into heap (native only).
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__free_heap(H5F_t *f, const unsigned char *buf, size_t nbytes)
+{
+    H5HG_t hobjid;
+    const uint8_t *p = (const uint8_t *)buf;
+    size_t buf_size;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_PACKAGE
+
+    HDassert(f);
+    HDassert(buf);
+
+    buf_size = H5HG_HEAP_ID_SIZE(f);
+    /* Don't decode if buffer size isn't big enough */
+    if(nbytes < buf_size)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Buffer size is too small")
+
+    /* Get the heap information */
+    H5F_addr_decode(f, &p, &(hobjid.addr));
+    if(!H5F_addr_defined(hobjid.addr) || hobjid.addr == 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "Undefined reference pointer")
+    UINT32DECODE(p, hobjid.idx);
+
+    /* Free heap object */
+    if(hobjid.addr > 0) {
+        /* Free heap object */
+        if(H5HG_remove(f, &hobjid) < 0)
+            HGOTO_ERROR(H5E_DATATYPE, H5E_WRITEERROR, FAIL, "Unable to remove heap object")
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__free_heap() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__decode_addr_compat
+ *
+ * Purpose: Decode an object address. (native only)
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__decode_addr_compat(hid_t id, H5I_type_t type, H5R_type_t ref_type,
+    const unsigned char *buf, haddr_t *addr_ptr)
+{
+    hid_t file_id = H5I_INVALID_HID;    /* File ID for region reference */
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_PACKAGE
+
+    if(ref_type == H5R_OBJECT1) {
+        size_t buf_size = H5R_OBJ_REF_BUF_SIZE;
+
+        /* Get object address */
+        if(H5R__decode_addr_obj_compat(buf, &buf_size, addr_ptr) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "unable to get object address")
+    } else {
+        void *vol_obj_file = NULL;
+        H5F_t *f = NULL;
+        size_t buf_size = H5R_DSET_REG_REF_BUF_SIZE;
+
+        /* Get the file for the object */
+        if((file_id = H5F_get_file_id(id, type, FALSE)) < 0)
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file or file object")
+
+        /* Retrieve VOL object */
+        if(NULL == (vol_obj_file = H5VL_vol_object(file_id)))
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+        /* Retrieve file from VOL object */
+        if(NULL == (f = (H5F_t *)H5VL_object_data(vol_obj_file)))
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid VOL object")
+
+        /* Get object address */
+        if(H5R__decode_addr_region_compat(f, buf, &buf_size, addr_ptr, NULL) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "unable to get object address")
+    }
+
+done:
+    if(file_id != H5I_INVALID_HID && H5I_dec_ref(file_id) < 0)
+        HDONE_ERROR(H5E_REFERENCE, H5E_CANTDEC, FAIL, "unable to decrement refcount on file")
+    FUNC_LEAVE_NOAPI(ret_value)
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__encode_addr_obj_compat
+ *
+ * Purpose: Encode an object address. (native only)
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__encode_addr_obj_compat(haddr_t addr, unsigned char *buf, size_t *nalloc)
+{
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_PACKAGE_NOERR
+
+    HDassert(nalloc);
+
+    /* Don't encode if buffer size isn't big enough or buffer is empty */
+    if(buf && *nalloc >= sizeof(addr))
+        H5MM_memcpy(buf, &addr, sizeof(addr));
+    *nalloc = sizeof(addr);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__encode_addr_obj_compat() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__decode_addr_obj_compat
+ *
+ * Purpose: Decode an object address. (native only)
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__decode_addr_obj_compat(const unsigned char *buf, size_t *nbytes,
+    haddr_t *addr_ptr)
+{
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_PACKAGE
+
+    HDassert(buf);
+    HDassert(nbytes);
+    HDassert(addr_ptr);
+
+    /* Don't decode if buffer size isn't big enough */
+    if(*nbytes < sizeof(*addr_ptr))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Buffer size is too small")
 
-    /* Get name, length, etc. */
-    if((ret_value = H5G_get_name_by_addr(f, &oloc, name, size)) < 0)
-        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, (-1), "can't determine name")
+    H5MM_memcpy(addr_ptr, buf, sizeof(*addr_ptr));
+
+    *nbytes = sizeof(*addr_ptr);
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5R__get_name() */
+} /* H5R__decode_addr_obj_compat() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__encode_addr_region_compat
+ *
+ * Purpose: Encode dataset selection and insert data into heap (native only).
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__encode_addr_region_compat(H5F_t *f, haddr_t obj_addr, H5S_t *space,
+    unsigned char *buf, size_t *nalloc)
+{
+    size_t buf_size;
+    unsigned char *data = NULL;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_PACKAGE
+
+    HDassert(f);
+    HDassert(space);
+    HDassert(nalloc);
+
+    /* Get required buffer size */
+    if(H5R__encode_heap(f, NULL, &buf_size, NULL, (size_t)0) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    if(buf && *nalloc >= buf_size) {
+        ssize_t data_size;
+        uint8_t *p;
+
+        /* Pass the correct encoding version for the selection depending on the
+         * file libver bounds, this is later retrieved in H5S hyper encode */
+        H5CX_set_libver_bounds(f);
+
+        /* Zero the heap ID out, may leak heap space if user is re-using
+         * reference and doesn't have garbage collection turned on
+         */
+        HDmemset(buf, 0, buf_size);
+
+        /* Get the amount of space required to serialize the selection */
+        if((data_size = H5S_SELECT_SERIAL_SIZE(space)) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTINIT, FAIL, "Invalid amount of space for serializing selection")
 
+        /* Increase buffer size to allow for the dataset OID */
+        data_size += (hssize_t)sizeof(haddr_t);
+
+        /* Allocate the space to store the serialized information */
+        H5_CHECK_OVERFLOW(data_size, hssize_t, size_t);
+        if(NULL == (data = (uint8_t *)H5MM_malloc((size_t)data_size)))
+            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
+
+        /* Serialize information for dataset OID into heap buffer */
+        p = (uint8_t *)data;
+        H5F_addr_encode(f, &p, obj_addr);
+
+        /* Serialize the selection into heap buffer */
+        if(H5S_SELECT_SERIALIZE(space, &p) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCOPY, FAIL, "Unable to serialize selection")
+
+        /* Write to heap */
+        if(H5R__encode_heap(f, buf, nalloc, data, (size_t)data_size) < 0)
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+    }
+    *nalloc = buf_size;
+
+done:
+    H5MM_free(data);
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5R__encode_addr_region_compat() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5R__decode_obj_addr_compat
+ *
+ * Purpose: Decode dataset selection from data inserted into heap (native only).
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5R__decode_addr_region_compat(H5F_t *f, const unsigned char *buf,
+    size_t *nbytes, haddr_t *obj_addr_ptr, H5S_t **space_ptr)
+{
+    unsigned char *data = NULL;
+    size_t data_size;
+    haddr_t obj_addr;
+    const uint8_t *p;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_PACKAGE
+
+    HDassert(f);
+    HDassert(buf);
+    HDassert(nbytes);
+
+    /* Read from heap */
+    if(H5R__decode_heap(f, buf, nbytes, &data, &data_size) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid location identifier")
+
+    /* Get object address */
+    p = (const uint8_t *)data;
+    H5F_addr_decode(f, &p, &obj_addr);
+    if(!H5F_addr_defined(obj_addr) || obj_addr == 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "Undefined reference pointer")
+
+    if(space_ptr) {
+        H5O_loc_t oloc; /* Object location */
+        H5S_t *space = NULL;
+
+        /* Initialize the object location */
+        H5O_loc_reset(&oloc);
+        oloc.file = f;
+        oloc.addr = obj_addr;
+
+        /* Open and copy the dataset's dataspace */
+        if(NULL == (space = H5S_read(&oloc)))
+            HGOTO_ERROR(H5E_DATASPACE, H5E_NOTFOUND, FAIL, "not found")
+
+        /* Unserialize the selection */
+        if(H5S_SELECT_DESERIALIZE(&space, &p) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "can't deserialize selection")
+
+        *space_ptr = space;
+    }
+    if(obj_addr_ptr)
+        *obj_addr_ptr = obj_addr;
+
+done:
+    H5MM_free(data);
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5R__decode_addr_region_compat() */
diff --git a/src/H5Rpkg.h b/src/H5Rpkg.h
index 1c1c8eb..1843bcf 100644
--- a/src/H5Rpkg.h
+++ b/src/H5Rpkg.h
@@ -36,11 +36,51 @@
 /* Package Private Macros */
 /**************************/
 
+/* Encode flags */
+#define H5R_IS_EXTERNAL         0x1     /* Set when encoding reference to external file */
+
+/* Macros for convenience */
+#define H5R_REF_FILENAME(x)     ((x)->ref.obj.filename)
+#define H5R_REF_ATTRNAME(x)     ((x)->ref.attr.name)
+
+/* Header size */
+#define H5R_ENCODE_HEADER_SIZE  (2 * H5_SIZEOF_UINT8_T)
 
 /****************************/
 /* Package Private Typedefs */
 /****************************/
 
+/* Object reference */
+typedef struct H5R_ref_priv_obj_t {
+    H5VL_token_t token;         /* Object token     */
+    char *filename;             /* File name        */
+} H5R_ref_priv_obj_t;
+
+/* Region reference */
+typedef struct H5R_ref_priv_reg_t {
+    H5R_ref_priv_obj_t obj;     /* Object reference */
+    H5S_t *space;               /* Selection        */
+} H5R_ref_priv_reg_t;
+
+/* Attribute reference */
+typedef struct H5R_ref_priv_attr_t {
+    H5R_ref_priv_obj_t obj;     /* Object reference */
+    char *name;                 /* Attribute name   */
+} H5R_ref_priv_attr_t;
+
+/* Generic reference type (keep it cache aligned) */
+typedef struct H5R_ref_priv_t {
+    union {
+        H5R_ref_priv_obj_t  obj;/* Object reference                 */
+        H5R_ref_priv_reg_t  reg;/* Region reference                 */
+        H5R_ref_priv_attr_t attr;/* Attribute Reference             */
+    } ref;
+    hid_t    loc_id;            /* Cached location identifier       */
+    uint32_t encode_size;       /* Cached encoding size             */
+    int8_t   type;              /* Reference type                   */
+    uint8_t  token_size;        /* Cached token size                */
+    char unused[18];            /* Unused                           */
+} H5R_ref_priv_t;
 
 /*****************************/
 /* Package Private Variables */
@@ -50,11 +90,41 @@
 /******************************/
 /* Package Private Prototypes */
 /******************************/
-H5_DLL herr_t H5R__create(void *ref, H5G_loc_t *loc, const char *name, H5R_type_t ref_type, H5S_t *space);
-H5_DLL hid_t H5R__dereference(H5F_t *file, hid_t dapl_id, H5R_type_t ref_type, const void *_ref);
-H5_DLL H5S_t *H5R__get_region(H5F_t *file, const void *_ref);
-H5_DLL herr_t H5R__get_obj_type(H5F_t *file, H5R_type_t ref_type, const void *_ref, H5O_type_t *obj_type);
-H5_DLL ssize_t H5R__get_name(H5F_t *file, H5R_type_t ref_type, const void *_ref, char *name, size_t size);
+H5_DLL herr_t   H5R__create_object(const H5VL_token_t *obj_token, size_t token_size, H5R_ref_priv_t *ref);
+H5_DLL herr_t   H5R__create_region(const H5VL_token_t *obj_token, size_t token_size, H5S_t *space, H5R_ref_priv_t *ref);
+H5_DLL herr_t   H5R__create_attr(const H5VL_token_t *obj_token, size_t token_size, const char *attr_name, H5R_ref_priv_t *ref);
+H5_DLL herr_t   H5R__destroy(H5R_ref_priv_t *ref);
+
+H5_DLL herr_t   H5R__set_loc_id(H5R_ref_priv_t *ref, hid_t id, hbool_t inc_ref);
+H5_DLL hid_t    H5R__get_loc_id(const H5R_ref_priv_t *ref);
+H5_DLL hid_t    H5R__reopen_file(H5R_ref_priv_t *ref, hid_t fapl_id);
+
+H5_DLL H5R_type_t   H5R__get_type(const H5R_ref_priv_t *ref);
+H5_DLL htri_t   H5R__equal(const H5R_ref_priv_t *ref1, const H5R_ref_priv_t *ref2);
+H5_DLL herr_t   H5R__copy(const H5R_ref_priv_t *src_ref, H5R_ref_priv_t *dst_ref);
+
+H5_DLL herr_t   H5R__get_obj_token(const H5R_ref_priv_t *ref, H5VL_token_t *obj_token, size_t *token_size);
+H5_DLL herr_t   H5R__set_obj_token(H5R_ref_priv_t *ref, const H5VL_token_t *obj_token, size_t token_size);
+H5_DLL herr_t   H5R__get_region(const H5R_ref_priv_t *ref, H5S_t *space);
+
+H5_DLL ssize_t  H5R__get_file_name(const H5R_ref_priv_t *ref, char *buf, size_t size);
+H5_DLL ssize_t  H5R__get_attr_name(const H5R_ref_priv_t *ref, char *buf, size_t size);
+
+H5_DLL herr_t   H5R__encode(const char *filename, const H5R_ref_priv_t *ref, unsigned char *buf, size_t *nalloc, unsigned flags);
+H5_DLL herr_t   H5R__decode(const unsigned char *buf, size_t *nbytes, H5R_ref_priv_t *ref);
+
+/* Native HDF5 specific routines */
+H5_DLL herr_t   H5R__encode_heap(H5F_t *f, unsigned char *buf, size_t *nalloc, const unsigned char *data, size_t data_size);
+H5_DLL herr_t   H5R__decode_heap(H5F_t *f, const unsigned char *buf, size_t *nbytes, unsigned char **data_ptr, size_t *data_size);
+H5_DLL herr_t   H5R__free_heap(H5F_t *f, const unsigned char *buf, size_t nbytes);
+
+H5_DLL herr_t   H5R__decode_addr_compat(hid_t id, H5I_type_t type, H5R_type_t ref_type, const unsigned char *buf, haddr_t *addr_ptr);
+
+H5_DLL herr_t   H5R__encode_addr_obj_compat(haddr_t obj_addr, unsigned char *buf, size_t *nalloc);
+H5_DLL herr_t   H5R__decode_addr_obj_compat(const unsigned char *buf, size_t *nbytes, haddr_t *obj_addr_ptr);
+
+H5_DLL herr_t   H5R__encode_addr_region_compat(H5F_t *f, haddr_t obj_addr, H5S_t *space, unsigned char *buf, size_t *nalloc);
+H5_DLL herr_t   H5R__decode_addr_region_compat(H5F_t *f, const unsigned char *buf, size_t *nbytes, haddr_t *obj_addr_ptr, H5S_t **space_ptr);
 
 #endif /* _H5Rpkg_H */
 
diff --git a/src/H5Rprivate.h b/src/H5Rprivate.h
index 1bf2e92..6afec47 100644
--- a/src/H5Rprivate.h
+++ b/src/H5Rprivate.h
@@ -25,6 +25,8 @@
 /* Library Private Macros */
 /**************************/
 
+#define H5R_ENCODE_VERSION      0x1     /* Version for encoding references */
+
 
 /****************************/
 /* Library Private Typedefs */
@@ -41,4 +43,3 @@
 /******************************/
 
 #endif  /* _H5Rprivate_H */
-
diff --git a/src/H5Rpublic.h b/src/H5Rpublic.h
index 598bafd..ce54ac4 100644
--- a/src/H5Rpublic.h
+++ b/src/H5Rpublic.h
@@ -26,47 +26,64 @@
 /* Public Macros */
 /*****************/
 
-/* Note! Be careful with the sizes of the references because they should really
- * depend on the run-time values in the file.  Unfortunately, the arrays need
- * to be defined at compile-time, so we have to go with the worst case sizes
- * for them.  -QAK
- */
+/* Deprecated reference buffer sizes that are kept for backward compatibility */
 #define H5R_OBJ_REF_BUF_SIZE        sizeof(haddr_t)
+#define H5R_DSET_REG_REF_BUF_SIZE   (sizeof(haddr_t) + 4)
 
-/* 4 is used instead of sizeof(int) to permit portability between the Crays
- * and other machines (the heap ID is always encoded as an int32 anyway).
+/* Default reference buffer size.
+ * Note! Be careful with the sizes of the references because they should really
+ * depend on the run-time values in the file.
  */
-#define H5R_DSET_REG_REF_BUF_SIZE   (sizeof(haddr_t) + 4)
+#define H5R_REF_BUF_SIZE            (64)
 
 /*******************/
 /* Public Typedefs */
 /*******************/
 
-/* Reference types */
-typedef enum H5R_type_t {
-    H5R_BADTYPE     =   (-1),   /* Invalid Reference Type               */
-    H5R_OBJECT,                 /* Object reference                     */
-    H5R_DATASET_REGION,         /* Dataset Region Reference             */
-    H5R_MAXTYPE                 /* Highest type (Invalid as true type)  */
+/*
+ * Reference types allowed.
+ * DO NOT CHANGE THE ORDER or VALUES as reference type values are encoded into
+ * the datatype message header.
+ */
+typedef enum {
+    H5R_BADTYPE     =   (-1),   /* Invalid reference type           */
+    H5R_OBJECT1     =     0,    /* Backward compatibility (object)  */
+    H5R_DATASET_REGION1 = 1,    /* Backward compatibility (region)  */
+    H5R_OBJECT2         = 2,    /* Object reference                 */
+    H5R_DATASET_REGION2 = 3,    /* Region reference                 */
+    H5R_ATTR            = 4,    /* Attribute Reference              */
+    H5R_MAXTYPE         = 5     /* Highest type (invalid)           */
 } H5R_type_t;
 
-/* Object reference structure for user's code
- * This needs to be large enough to store largest haddr_t on a worst case
- * machine (8 bytes currently).
+/* Deprecated types are kept for backward compatibility with previous versions */
+
+/**
+ * Deprecated object reference type that is used with deprecated reference APIs.
+ * Note! This type can only be used with the "native" HDF5 VOL connector.
  */
 typedef haddr_t hobj_ref_t;
 
-/* Dataset Region reference structure for user's code
+/**
+ * Dataset region reference type that is used with deprecated reference APIs.
  * (Buffer to store heap ID and index)
  * This needs to be large enough to store largest haddr_t in a worst case
- * machine (8 bytes currently) plus an int
+ * machine (8 bytes currently) plus an int.
+ * Note! This type can only be used with the "native" HDF5 VOL connector.
  */
 typedef unsigned char hdset_reg_ref_t[H5R_DSET_REG_REF_BUF_SIZE];
 
+/**
+ * Opaque reference type. The same reference type is used for object,
+ * dataset region and attribute references. This is the type that
+ * should always be used with the current reference API.
+ */
+typedef unsigned char H5R_ref_t[H5R_REF_BUF_SIZE];
+
 /********************/
 /* Public Variables */
 /********************/
 
+
 /*********************/
 /* Public Prototypes */
 /*********************/
@@ -75,30 +92,57 @@ typedef unsigned char hdset_reg_ref_t[H5R_DSET_REG_REF_BUF_SIZE];
 extern "C" {
 #endif
 
-H5_DLL herr_t H5Rcreate(void *ref, hid_t loc_id, const char *name,
-			 H5R_type_t ref_type, hid_t space_id);
-H5_DLL hid_t H5Rdereference2(hid_t obj_id, hid_t oapl_id, H5R_type_t ref_type, const void *ref);
-H5_DLL hid_t H5Rget_region(hid_t dataset, H5R_type_t ref_type, const void *ref);
-H5_DLL herr_t H5Rget_obj_type2(hid_t id, H5R_type_t ref_type, const void *_ref,
-    H5O_type_t *obj_type);
-H5_DLL ssize_t H5Rget_name(hid_t loc_id, H5R_type_t ref_type, const void *ref,
-    char *name /*out*/, size_t size);
+/* Constructors */
+H5_DLL herr_t   H5Rcreate_object(hid_t loc_id, const char *name, H5R_ref_t *ref_ptr);
+H5_DLL herr_t   H5Rcreate_region(hid_t loc_id, const char *name, hid_t space_id, H5R_ref_t *ref_ptr);
+H5_DLL herr_t   H5Rcreate_attr(hid_t loc_id, const char *name, const char *attr_name, H5R_ref_t *ref_ptr);
+H5_DLL herr_t   H5Rdestroy(H5R_ref_t *ref_ptr);
+
+/* Info */
+H5_DLL H5R_type_t   H5Rget_type(const H5R_ref_t *ref_ptr);
+H5_DLL htri_t   H5Requal(const H5R_ref_t *ref1_ptr, const H5R_ref_t *ref2_ptr);
+H5_DLL herr_t   H5Rcopy(const H5R_ref_t *src_ref_ptr, H5R_ref_t *dst_ref_ptr);
+
+/* Dereference */
+H5_DLL hid_t    H5Ropen_object(const H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t oapl_id);
+H5_DLL hid_t    H5Ropen_region(const H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t oapl_id);
+H5_DLL hid_t    H5Ropen_attr(const H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t aapl_id);
+
+/* Get type */
+H5_DLL herr_t   H5Rget_obj_type3(const H5R_ref_t *ref_ptr, hid_t rapl_id, H5O_type_t *obj_type);
+
+/* Get name */
+H5_DLL ssize_t  H5Rget_file_name(const H5R_ref_t *ref_ptr, char *buf, size_t size);
+H5_DLL ssize_t  H5Rget_obj_name(const H5R_ref_t *ref_ptr, hid_t rapl_id, char *buf, size_t size);
+H5_DLL ssize_t  H5Rget_attr_name(const H5R_ref_t *ref_ptr, char *buf, size_t size);
 
 /* Symbols defined for compatibility with previous versions of the HDF5 API.
  *
- * Use of these symbols is deprecated.
+ * Use of these symbols is or will be deprecated.
  */
-#ifndef H5_NO_DEPRECATED_SYMBOLS
+
+/* Macros */
+
+/* Versions for compatibility */
+#define H5R_OBJECT          H5R_OBJECT1
+#define H5R_DATASET_REGION  H5R_DATASET_REGION1
 
 /* Function prototypes */
-H5_DLL H5G_obj_t H5Rget_obj_type1(hid_t id, H5R_type_t ref_type, const void *_ref);
+#ifndef H5_NO_DEPRECATED_SYMBOLS
+
+H5_DLL H5G_obj_t H5Rget_obj_type1(hid_t id, H5R_type_t ref_type, const void *ref);
 H5_DLL hid_t H5Rdereference1(hid_t obj_id, H5R_type_t ref_type, const void *ref);
 
 #endif /* H5_NO_DEPRECATED_SYMBOLS */
 
+H5_DLL herr_t H5Rcreate(void *ref, hid_t loc_id, const char *name, H5R_type_t ref_type, hid_t space_id);
+H5_DLL herr_t H5Rget_obj_type2(hid_t id, H5R_type_t ref_type, const void *ref, H5O_type_t *obj_type);
+H5_DLL hid_t H5Rdereference2(hid_t obj_id, hid_t oapl_id, H5R_type_t ref_type, const void *ref);
+H5_DLL hid_t H5Rget_region(hid_t dataset, H5R_type_t ref_type, const void *ref);
+H5_DLL ssize_t H5Rget_name(hid_t loc_id, H5R_type_t ref_type, const void *ref, char *name, size_t size);
+
 #ifdef __cplusplus
 }
 #endif
 
 #endif  /* _H5Rpublic_H */
-
diff --git a/src/H5S.c b/src/H5S.c
index 6018798..ddfd064 100644
--- a/src/H5S.c
+++ b/src/H5S.c
@@ -1357,7 +1357,6 @@ H5S_set_extent_simple(H5S_t *space, unsigned rank, const hsize_t *dims,
 
     /* Check args */
     HDassert(rank <= H5S_MAX_RANK);
-    HDassert(0 == rank || dims);
 
     /* shift out of the previous state to a "simple" dataspace.  */
     if(H5S__extent_release(&space->extent) < 0)
@@ -1378,7 +1377,7 @@ H5S_set_extent_simple(H5S_t *space, unsigned rank, const hsize_t *dims,
         space->extent.size = (hsize_t *)H5FL_ARR_MALLOC(hsize_t, (size_t)rank);
 
         /* Copy the dimensions & compute the number of elements in the extent */
-        for(u = 0, nelem = 1; u < space->extent.rank; u++) {
+        for(u = 0, nelem = 1; dims && (u < space->extent.rank); u++) {
             space->extent.size[u] = dims[u];
             nelem *= dims[u];
         } /* end for */
@@ -1390,7 +1389,7 @@ H5S_set_extent_simple(H5S_t *space, unsigned rank, const hsize_t *dims,
         if(max != NULL)
             H5MM_memcpy(space->extent.max, max, sizeof(hsize_t) * rank);
         else
-            for(u = 0; u < space->extent.rank; u++)
+            for(u = 0; dims && (u < space->extent.rank); u++)
                 space->extent.max[u] = dims[u];
     } /* end else */
 
diff --git a/src/H5T.c b/src/H5T.c
index fd48d6a..f368fdb 100644
--- a/src/H5T.c
+++ b/src/H5T.c
@@ -226,18 +226,34 @@
 #define H5T_INIT_TYPE_REF_COMMON {                          \
     H5T_INIT_TYPE_ALLOC_COMMON(H5T_REFERENCE)               \
     H5T_INIT_TYPE_NUM_COMMON(H5T_ORDER_NONE)                \
+    dt->shared->force_conv = TRUE;                          \
+    dt->shared->u.atomic.u.r.f = NULL;                      \
+    dt->shared->u.atomic.u.r.loc = H5T_LOC_BADLOC;          \
+    dt->shared->u.atomic.u.r.cls = NULL;                    \
 }
 
 #define H5T_INIT_TYPE_OBJREF_CORE {                         \
     H5T_INIT_TYPE_REF_COMMON                                \
-    dt->shared->force_conv = TRUE;                          \
-    dt->shared->u.atomic.u.r.rtype = H5R_OBJECT;            \
-    dt->shared->u.atomic.u.r.loc = H5T_LOC_MEMORY;          \
+    dt->shared->u.atomic.u.r.rtype = H5R_OBJECT1;           \
+    dt->shared->u.atomic.u.r.opaque = FALSE;                \
+    dt->shared->u.atomic.u.r.version = 0;                   \
 }
 
 #define H5T_INIT_TYPE_REGREF_CORE {                         \
     H5T_INIT_TYPE_REF_COMMON                                \
-    dt->shared->u.atomic.u.r.rtype = H5R_DATASET_REGION;    \
+    dt->shared->u.atomic.u.r.rtype = H5R_DATASET_REGION1;   \
+    dt->shared->u.atomic.u.r.opaque = FALSE;                \
+    dt->shared->u.atomic.u.r.version = 0;                   \
+}
+
+/* rtype value is only used as a placeholder to differentiate the type from
+ * other types, any opaque (i.e. "new") reference type could be used.
+ */
+#define H5T_INIT_TYPE_REF_CORE {                            \
+    H5T_INIT_TYPE_REF_COMMON                                \
+    dt->shared->u.atomic.u.r.rtype = H5R_OBJECT2;           \
+    dt->shared->u.atomic.u.r.opaque = TRUE;                 \
+    dt->shared->u.atomic.u.r.version = H5R_ENCODE_VERSION;  \
 }
 
 /* Define the code templates for the "SIZE_TMPL" in the H5T_INIT_TYPE macro */
@@ -295,7 +311,7 @@ static htri_t H5T__compiler_conv(H5T_t *src, H5T_t *dst);
 static herr_t H5T__set_size(H5T_t *dt, size_t size);
 static herr_t H5T__close_cb(H5T_t *dt);
 static H5T_path_t *H5T__path_find_real(const H5T_t *src, const H5T_t *dst, const char *name, H5T_conv_func_t *conv);
-static hbool_t H5T__detect_reg_ref(const H5T_t *dt);
+static hbool_t H5T__detect_vlen_ref(const H5T_t *dt);
 
 
 /*****************************/
@@ -354,6 +370,7 @@ hid_t H5T_STD_B64BE_g           = FAIL;
 hid_t H5T_STD_B64LE_g           = FAIL;
 hid_t H5T_STD_REF_OBJ_g         = FAIL;
 hid_t H5T_STD_REF_DSETREG_g     = FAIL;
+hid_t H5T_STD_REF_g             = FAIL;
 
 hid_t H5T_UNIX_D32BE_g          = FAIL;
 hid_t H5T_UNIX_D32LE_g          = FAIL;
@@ -444,6 +461,7 @@ size_t H5T_POINTER_COMP_ALIGN_g             = 0;
 size_t H5T_HVL_COMP_ALIGN_g                 = 0;
 size_t H5T_HOBJREF_COMP_ALIGN_g             = 0;
 size_t H5T_HDSETREGREF_COMP_ALIGN_g         = 0;
+size_t H5T_REF_COMP_ALIGN_g                 = 0;
 
 /*
  * Alignment constraints for native types. These are initialized at run time
@@ -737,7 +755,9 @@ H5T__init_package(void)
     H5T_t       *enum_type=NULL;        /* Datatype structure for enum objects */
     H5T_t       *vlen=NULL;             /* Datatype structure for vlen objects */
     H5T_t       *array=NULL;            /* Datatype structure for array objects */
-    H5T_t       *objref=NULL;           /* Datatype structure for object reference objects */
+    H5T_t       *objref=NULL;           /* Datatype structure for deprecated reference objects */
+    H5T_t       *regref=NULL;           /* Datatype structure for deprecated region references */
+    H5T_t       *ref=NULL;              /* Datatype structure for opaque references */
     hsize_t     dim[1]={1};             /* Dimension info for array datatype */
     herr_t      status;
     hbool_t     copied_dtype = TRUE;    /* Flag to indicate whether datatype was copied or allocated (for error cleanup) */
@@ -989,12 +1009,23 @@ H5T__init_package(void)
      *------------------------------------------------------------
      */
 
-    /* Object reference (i.e. object header address in file) */
-    H5T_INIT_TYPE(OBJREF, H5T_STD_REF_OBJ_g, ALLOC, -, SET, H5R_OBJ_REF_BUF_SIZE)
+    /* Deprecated object reference type */
+    H5T_INIT_TYPE(OBJREF, H5T_STD_REF_OBJ_g, ALLOC, -, NOSET, -)
+    if(H5T_set_loc(dt, NULL, H5T_LOC_MEMORY) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "invalid datatype location")
     objref = dt;    /* Keep type for later */
 
-    /* Dataset Region reference (i.e. selection inside a dataset) */
-    H5T_INIT_TYPE(REGREF, H5T_STD_REF_DSETREG_g, ALLOC, -, SET, H5R_DSET_REG_REF_BUF_SIZE)
+    /* Deprecated region reference type */
+    H5T_INIT_TYPE(REGREF, H5T_STD_REF_DSETREG_g, ALLOC, -, NOSET, -)
+    if(H5T_set_loc(dt, NULL, H5T_LOC_MEMORY) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "invalid datatype location")
+    regref = dt;    /* Keep type for later */
+
+    /* Opaque reference type */
+    H5T_INIT_TYPE(REF, H5T_STD_REF_g, ALLOC, -, NOSET, -)
+    if(H5T_set_loc(dt, NULL, H5T_LOC_MEMORY) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "invalid datatype location")
+    ref = dt;       /* Keep type for later */
 
     /*
      * Register conversion functions beginning with the most general and
@@ -1030,6 +1061,10 @@ H5T__init_package(void)
     status |= H5T__register_int(H5T_PERS_SOFT, "vlen", vlen, vlen, H5T__conv_vlen);
     status |= H5T__register_int(H5T_PERS_SOFT, "array", array, array, H5T__conv_array);
     status |= H5T__register_int(H5T_PERS_SOFT, "objref", objref, objref, H5T__conv_order_opt);
+    status |= H5T__register_int(H5T_PERS_SOFT, "regref", regref, regref, H5T__conv_noop);
+    status |= H5T__register_int(H5T_PERS_SOFT, "ref", ref, ref, H5T__conv_ref);
+    status |= H5T__register_int(H5T_PERS_SOFT, "objref_ref", objref, ref, H5T__conv_ref);
+    status |= H5T__register_int(H5T_PERS_SOFT, "regref_ref", regref, ref, H5T__conv_ref);
 
     /*
      * Native conversions should be listed last since we can use hardware to
@@ -1473,6 +1508,7 @@ H5T_top_term_package(void)
             H5T_STD_B64LE_g             = FAIL;
             H5T_STD_REF_OBJ_g           = FAIL;
             H5T_STD_REF_DSETREG_g       = FAIL;
+            H5T_STD_REF_g               = FAIL;
 
             H5T_UNIX_D32BE_g            = FAIL;
             H5T_UNIX_D32LE_g            = FAIL;
@@ -2883,6 +2919,56 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:    H5Treclaim
+ *
+ * Purpose: Frees the buffers allocated for storing variable-length data
+ *      in memory.  Only frees the VL data in the selection defined in the
+ *      dataspace.  The dataset transfer property list is required to find the
+ *      correct allocation/free methods for the VL data in the buffer.
+ *
+ * Return:  Non-negative on success, negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              Thursday, June 10, 1999
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Treclaim(hid_t type_id, hid_t space_id, hid_t dxpl_id, void *buf)
+{
+    H5S_t *space;               /* Dataspace for iteration */
+    herr_t ret_value;           /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE4("e", "iii*x", type_id, space_id, dxpl_id, buf);
+
+    /* Check args */
+    if(H5I_DATATYPE != H5I_get_type(type_id) || buf == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid argument")
+    if(NULL == (space = (H5S_t *)H5I_object_verify(space_id, H5I_DATASPACE)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid dataspace")
+    if(!(H5S_has_extent(space)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "dataspace does not have extent set")
+
+    /* Get the default dataset transfer property list if the user didn't provide one */
+    if(H5P_DEFAULT == dxpl_id)
+        dxpl_id = H5P_DATASET_XFER_DEFAULT;
+    else
+        if(TRUE != H5P_isa_class(dxpl_id, H5P_DATASET_XFER))
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not xfer parms")
+
+    /* Set DXPL for operation */
+    H5CX_set_dxpl(dxpl_id);
+
+    /* Call internal routine */
+    ret_value = H5T_reclaim(type_id, space, buf);
+
+done:
+    FUNC_LEAVE_API(ret_value)
+}   /* end H5Treclaim() */
+
+
+/*-------------------------------------------------------------------------
  * Function:  H5Tencode
  *
  * Purpose:   Given an datatype ID, converts the object description into
@@ -4456,28 +4542,10 @@ H5T_cmp(const H5T_t *dt1, const H5T_t *dt2, hbool_t superset)
                         HGOTO_DONE(-1);
                     if(dt1->shared->u.atomic.u.r.rtype > dt2->shared->u.atomic.u.r.rtype)
                         HGOTO_DONE(1);
-
-                    switch(dt1->shared->u.atomic.u.r.rtype) {
-                        case H5R_OBJECT:
-                            if(dt1->shared->u.atomic.u.r.loc < dt2->shared->u.atomic.u.r.loc)
-                                HGOTO_DONE(-1);
-                            if(dt1->shared->u.atomic.u.r.loc > dt2->shared->u.atomic.u.r.loc)
-                                HGOTO_DONE(1);
-                            break;
-
-                        case H5R_DATASET_REGION:
-                    /* Does this need more to distinguish it? -QAK 11/30/98 */
-                            /*void */
-                            break;
-
-                        case H5R_BADTYPE:
-                        case H5R_MAXTYPE:
-                            HDassert("invalid type" && 0);
-                            break;
-                        default:
-                            HDassert("not implemented yet" && 0);
-                            break;
-                    }
+                    if(dt1->shared->u.atomic.u.r.loc < dt2->shared->u.atomic.u.r.loc)
+                        HGOTO_DONE(-1);
+                    if(dt1->shared->u.atomic.u.r.loc > dt2->shared->u.atomic.u.r.loc)
+                        HGOTO_DONE(1);
                     break;
 
                 case H5T_NO_CLASS:
@@ -5330,7 +5398,7 @@ done:
     htri_t H5T_set_loc(dt,f,loc)
         H5T_t *dt;              IN/OUT: Pointer to the datatype to mark
         H5F_t *f;               IN: Pointer to the file the datatype is in
-        H5T_vlen_type_t loc     IN: location of type
+        H5T_loc_t loc           IN: location of type
 
  RETURNS
     One of two values on success:
@@ -5455,17 +5523,9 @@ H5T_set_loc(H5T_t *dt, H5F_t *f, H5T_loc_t loc)
                 break;
 
             case H5T_REFERENCE:
-                /* Only need to change location of object references */
-                if(dt->shared->u.atomic.u.r.rtype == H5R_OBJECT) {
-                    /* Mark this reference */
-                    if(loc != dt->shared->u.atomic.u.r.loc) {
-                        /* Set the location */
-                        dt->shared->u.atomic.u.r.loc = loc;
-
-                        /* Indicate that the location changed */
-                        ret_value = TRUE;
-                    } /* end if */
-                } /* end if */
+                /* Reference types go through type conversion */
+                if((ret_value = H5T__ref_set_loc(dt, f, loc)) < 0)
+                    HGOTO_ERROR(H5E_DATATYPE, H5E_CANTSET, FAIL, "Unable to set reference location");
                 break;
 
             case H5T_NO_CLASS:
@@ -5492,7 +5552,7 @@ done:
  *
  * Purpose:     Check if a datatype will change between disk and memory.
  *
- * Notes:       Currently, only variable-length and object references change
+ * Notes:       Currently, only variable-length and references change
  *              between disk & memory (see cases where things are changed in
  *              the H5T_set_loc() code above).
  *
@@ -5527,9 +5587,9 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:   H5T_detect_reg_ref
+ * Function:   H5T__detect_vlen_ref
  *
- * Purpose:    Check whether a datatype contains (or is) a region reference
+ * Purpose:    Check whether a datatype contains (or is) a vlen reference
  *             datatype.
  *
  * Return:      TRUE (1) or FALSE (0) on success
@@ -5541,7 +5601,7 @@ done:
  *-------------------------------------------------------------------------
  */
 static hbool_t
-H5T__detect_reg_ref(const H5T_t *dt)
+H5T__detect_vlen_ref(const H5T_t *dt)
 {
     unsigned    u;                      /* Local index variable */
     hbool_t     ret_value = FALSE;      /* Return value */
@@ -5551,8 +5611,9 @@ H5T__detect_reg_ref(const H5T_t *dt)
     /* Sanity checks */
     HDassert(dt);
 
-    /* Check if this datatype is a region reference */
-    if(H5T_REFERENCE == dt->shared->type && H5R_DATASET_REGION == dt->shared->u.atomic.u.r.rtype)
+    /* Check if this datatype is a vlen reference */
+    /* TODO currently H5T_STD_REF is always considered as a vlen type */
+    if(H5T_REFERENCE == dt->shared->type && !dt->shared->u.atomic.u.r.opaque)
         HGOTO_DONE(TRUE);
 
     /* Check for types that might have the correct type as a component */
@@ -5561,14 +5622,14 @@ H5T__detect_reg_ref(const H5T_t *dt)
             /* Iterate over all the compound datatype's fields */
             for(u = 0; u < dt->shared->u.compnd.nmembs; u++)
                 /* Recurse on field's datatype */
-                if(H5T__detect_reg_ref(dt->shared->u.compnd.memb[u].type))
+                if(H5T__detect_vlen_ref(dt->shared->u.compnd.memb[u].type))
                     HGOTO_DONE(TRUE);
             break;
 
         case H5T_ARRAY:
         case H5T_VLEN:
         case H5T_ENUM:
-            HGOTO_DONE(H5T__detect_reg_ref(dt->shared->parent));
+            HGOTO_DONE(H5T__detect_vlen_ref(dt->shared->parent));
             break;
 
         case H5T_NO_CLASS:
@@ -5586,7 +5647,7 @@ H5T__detect_reg_ref(const H5T_t *dt)
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5T__detect_reg_ref() */
+} /* end H5T__detect_vlen_ref() */
 
 
 /*-------------------------------------------------------------------------
@@ -5622,7 +5683,7 @@ H5T_is_vl_storage(const H5T_t *dt)
     if(H5T_detect_class(dt, H5T_VLEN, FALSE))
         ret_value = TRUE;
     else if(H5T_detect_class(dt, H5T_REFERENCE, FALSE))
-        ret_value = H5T__detect_reg_ref(dt);
+        ret_value = H5T__detect_vlen_ref(dt);
     else
         ret_value = FALSE;
 
diff --git a/src/H5Tconv.c b/src/H5Tconv.c
index 723b9f2..84642f4 100644
--- a/src/H5Tconv.c
+++ b/src/H5Tconv.c
@@ -1018,6 +1018,9 @@ H5FL_BLK_DEFINE_STATIC(vlen_seq);
 /* Declare a free list to manage pieces of array data */
 H5FL_BLK_DEFINE_STATIC(array_seq);
 
+/* Declare a free list to manage pieces of reference data */
+H5FL_BLK_DEFINE_STATIC(ref_seq);
+
 
 /*-------------------------------------------------------------------------
  * Function:	H5T__conv_noop
@@ -3476,6 +3479,195 @@ done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5T__conv_array() */
 
+/*-------------------------------------------------------------------------
+ * Function:    H5T__conv_ref
+ *
+ * Purpose: Converts between reference datatypes in memory and on disk.
+ *      This is a soft conversion function.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5T__conv_ref(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, size_t nelmts,
+    size_t buf_stride, size_t bkg_stride, void *buf, void *bkg)
+{
+    H5T_t   *src = NULL;        /* source datatype                      */
+    H5T_t   *dst = NULL;        /* destination datatype                 */
+    uint8_t *s = NULL;          /* source buffer                        */
+    uint8_t *d = NULL;          /* destination buffer                   */
+    uint8_t *b = NULL;          /* background buffer                    */
+    ssize_t s_stride, d_stride; /* src and dst strides                  */
+    ssize_t b_stride;           /* bkg stride                           */
+    size_t  safe;               /* how many elements are safe to process in each pass */
+    void    *conv_buf = NULL;   /* temporary conversion buffer          */
+    size_t  conv_buf_size = 0;  /* size of conversion buffer in bytes   */
+    size_t  elmtno;             /* element number counter               */
+    herr_t ret_value = SUCCEED; /* return value                         */
+
+    FUNC_ENTER_PACKAGE
+
+    switch(cdata->command) {
+        case H5T_CONV_INIT:
+            /*
+             * First, determine if this conversion function applies to the
+             * conversion path SRC_ID-->DST_ID.  If not, return failure;
+             * otherwise initialize the `priv' field of `cdata' with
+             * information that remains (almost) constant for this
+             * conversion path.
+             */
+            if(NULL == (src = (H5T_t *)H5I_object(src_id)) || NULL == (dst = (H5T_t *)H5I_object(dst_id)))
+                HGOTO_ERROR(H5E_DATATYPE, H5E_BADTYPE, FAIL, "not a datatype")
+            if(H5T_REFERENCE != src->shared->type)
+                HGOTO_ERROR(H5E_DATATYPE, H5E_BADTYPE, FAIL, "not a H5T_REFERENCE datatype")
+            if(H5T_REFERENCE != dst->shared->type)
+                HGOTO_ERROR(H5E_DATATYPE, H5E_BADTYPE, FAIL, "not a H5T_REFERENCE datatype")
+            /* Only allow for source reference that is not an opaque type, destination must be opaque */
+            if(!dst->shared->u.atomic.u.r.opaque)
+                HGOTO_ERROR(H5E_DATATYPE, H5E_BADTYPE, FAIL, "not an H5T_STD_REF datatype")
+
+            /* Reference types don't need a background buffer */
+            cdata->need_bkg = H5T_BKG_NO;
+            break;
+
+        case H5T_CONV_FREE:
+            break;
+
+        case H5T_CONV_CONV:
+        {
+            /*
+             * Conversion.
+             */
+            if(NULL == (src = (H5T_t *)H5I_object(src_id)) || NULL == (dst = (H5T_t *)H5I_object(dst_id)))
+                HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a datatype")
+
+            HDassert(src->shared->u.atomic.u.r.cls);
+
+            /* Initialize source & destination strides */
+            if(buf_stride) {
+                HDassert(buf_stride >= src->shared->size);
+                HDassert(buf_stride >= dst->shared->size);
+                H5_CHECK_OVERFLOW(buf_stride, size_t, ssize_t);
+                s_stride = d_stride = (ssize_t)buf_stride;
+            } /* end if */
+            else {
+                H5_CHECK_OVERFLOW(src->shared->size, size_t, ssize_t);
+                H5_CHECK_OVERFLOW(dst->shared->size, size_t, ssize_t);
+                s_stride = (ssize_t)src->shared->size;
+                d_stride = (ssize_t)dst->shared->size;
+            } /* end else */
+            if(bkg) {
+                if(bkg_stride)
+                    b_stride = (ssize_t)bkg_stride;
+                else
+                    b_stride = d_stride;
+            } /* end if */
+            else
+                b_stride = 0;
+
+            /* The outer loop of the type conversion macro, controlling which */
+            /* direction the buffer is walked */
+            while(nelmts > 0) {
+                /* Check if we need to go backwards through the buffer */
+                if(d_stride > s_stride) {
+                    /* Sanity check */
+                    HDassert(s_stride > 0);
+                    HDassert(d_stride > 0);
+                    HDassert(b_stride >= 0);
+
+                    /* Compute the number of "safe" destination elements at */
+                    /* the end of the buffer (Those which don't overlap with */
+                    /* any source elements at the beginning of the buffer) */
+                    safe = nelmts - (((nelmts * (size_t)s_stride) + ((size_t)d_stride - 1)) / (size_t)d_stride);
+
+                    /* If we're down to the last few elements, just wrap up */
+                    /* with a "real" reverse copy */
+                    if(safe < 2) {
+                        s = (uint8_t *)buf + (nelmts - 1) * (size_t)s_stride;
+                        d = (uint8_t *)buf + (nelmts - 1) * (size_t)d_stride;
+                        b = (uint8_t *)bkg + (nelmts - 1) * (size_t)b_stride;
+                        s_stride = -s_stride;
+                        d_stride = -d_stride;
+                        b_stride = -b_stride;
+
+                        safe = nelmts;
+                    } /* end if */
+                    else {
+                        s = (uint8_t *)buf + (nelmts - safe) * (size_t)s_stride;
+                        d = (uint8_t *)buf + (nelmts - safe) * (size_t)d_stride;
+                        b = (uint8_t *)bkg + (nelmts - safe) * (size_t)b_stride;
+                    } /* end else */
+                } /* end if */
+                else {
+                    /* Single forward pass over all data */
+                    s = d = (uint8_t *)buf;
+                    b = (uint8_t *)bkg;
+                    safe = nelmts;
+                } /* end else */
+
+                for(elmtno = 0; elmtno < safe; elmtno++) {
+                    size_t buf_size;
+                    hbool_t dst_copy = FALSE;
+
+                    /* Get size of references */
+                    if(0 == (buf_size = src->shared->u.atomic.u.r.cls->getsize(
+                        src->shared->u.atomic.u.r.f, s, src->shared->size,
+                        dst->shared->u.atomic.u.r.f, &dst_copy)))
+                        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "incorrect size")
+
+                    /* Check if conversion buffer is large enough, resize if necessary. */
+                    if(conv_buf_size < buf_size) {
+                        conv_buf_size = buf_size;
+                        if(NULL == (conv_buf = H5FL_BLK_REALLOC(ref_seq, conv_buf, conv_buf_size)))
+                            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for type conversion")
+                        HDmemset(conv_buf, 0, conv_buf_size);
+                    } /* end if */
+
+                    if(dst_copy && (src->shared->u.atomic.u.r.loc == H5T_LOC_DISK)) {
+                        H5MM_memcpy(conv_buf, s, buf_size);
+                    } else {
+                        /* Read reference */
+                        if(src->shared->u.atomic.u.r.cls->read(
+                            src->shared->u.atomic.u.r.f, s, src->shared->size,
+                            dst->shared->u.atomic.u.r.f, conv_buf, buf_size) < 0)
+                            HGOTO_ERROR(H5E_DATATYPE, H5E_READERROR, FAIL, "can't read reference data")
+                    }
+
+                    if(dst_copy && (dst->shared->u.atomic.u.r.loc == H5T_LOC_DISK)) {
+                        H5MM_memcpy(d, conv_buf, buf_size);
+                    } else {
+                        /* Write reference to destination location */
+                        if(dst->shared->u.atomic.u.r.cls->write(
+                            src->shared->u.atomic.u.r.f, conv_buf, buf_size, src->shared->u.atomic.u.r.rtype,
+                            dst->shared->u.atomic.u.r.f, d, dst->shared->size, b) < 0)
+                            HGOTO_ERROR(H5E_DATATYPE, H5E_WRITEERROR, FAIL, "can't write reference data")
+                    }
+
+                    /* Advance pointers */
+                    s += s_stride;
+                    d += d_stride;
+                    b += b_stride;
+                } /* end for */
+
+                /* Decrement number of elements left to convert */
+                nelmts -= safe;
+            } /* end while */
+        } /* end case */
+            break;
+
+        default:    /* Some other command we don't know about yet.*/
+            HGOTO_ERROR(H5E_DATATYPE, H5E_UNSUPPORTED, FAIL, "unknown conversion command")
+    }   /* end switch */
+
+done:
+    /* Release the conversion buffer (always allocated, except on errors) */
+    if(conv_buf)
+        conv_buf = H5FL_BLK_FREE(ref_seq, conv_buf);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5T__conv_ref() */
+
 
 /*-------------------------------------------------------------------------
  * Function:	H5T__conv_i_i
@@ -9307,3 +9499,84 @@ H5T_reverse_order(uint8_t *rev, uint8_t *s, size_t size, H5T_order_t order)
     FUNC_LEAVE_NOAPI(SUCCEED)
 }
 
+
+/*-------------------------------------------------------------------------
+ * Function:    H5T_reclaim
+ *
+ * Purpose: Frees the buffers allocated for storing variable-length data
+ *          in memory. Only frees the VL data in the selection defined in the
+ *          dataspace.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5T_reclaim(hid_t type_id, H5S_t *space, void *buf)
+{
+    H5T_t *type;                /* Datatype */
+    H5S_sel_iter_op_t dset_op;  /* Operator for iteration */
+    H5T_vlen_alloc_info_t vl_alloc_info;   /* VL allocation info */
+    herr_t ret_value = FAIL;    /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT
+
+    /* Check args */
+    HDassert(H5I_DATATYPE == H5I_get_type(type_id));
+    HDassert(space);
+    HDassert(buf);
+
+    if(NULL == (type = (H5T_t *)H5I_object_verify(type_id, H5I_DATATYPE)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an valid base datatype")
+
+    /* Get the allocation info */
+    if(H5CX_get_vlen_alloc_info(&vl_alloc_info) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTGET, FAIL, "unable to retrieve VL allocation info")
+
+    /* Call H5S_select_iterate with args, etc. */
+    dset_op.op_type = H5S_SEL_ITER_OP_LIB;
+    dset_op.u.lib_op = H5T_reclaim_cb;
+
+    ret_value = H5S_select_iterate(buf, type, space, &dset_op, &vl_alloc_info);
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T_reclaim() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5T_reclaim_cb
+ *
+ * Purpose: Iteration callback to reclaim conversion allocated memory for a
+ *          buffer element.
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5T_reclaim_cb(void *elem, const H5T_t *dt, unsigned H5_ATTR_UNUSED ndim,
+    const hsize_t H5_ATTR_UNUSED *point, void *op_data)
+{
+    herr_t ret_value = SUCCEED;     /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT
+
+    /* Sanity check */
+    HDassert(elem);
+    HDassert(dt);
+
+    if(dt->shared->type == H5T_REFERENCE) {
+        if(H5T_ref_reclaim(elem, dt) < 0)
+            HGOTO_ERROR(H5E_DATATYPE, H5E_CANTFREE, FAIL, "can't reclaim ref elements")
+    } else {
+        HDassert(op_data);
+
+        /* Allow vlen reclaim to recurse into that routine */
+        if(H5T_vlen_reclaim(elem, dt, (H5T_vlen_alloc_info_t *)op_data) < 0)
+            HGOTO_ERROR(H5E_DATATYPE, H5E_CANTFREE, FAIL, "can't reclaim vlen elements")
+    }
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5T_reclaim_cb() */
diff --git a/src/H5Tnative.c b/src/H5Tnative.c
index 6daa544..1d203c7 100644
--- a/src/H5Tnative.c
+++ b/src/H5Tnative.c
@@ -126,7 +126,6 @@ static H5T_t *
 H5T__get_native_type(H5T_t *dtype, H5T_direction_t direction, size_t *struct_align,
     size_t *offset, size_t *comp_size)
 {
-    H5T_t       *dt;                /* Datatype to make native */
     H5T_t       *super_type;        /* Super type of VL, array and enum datatypes */
     H5T_t       *nat_super_type;    /* Native form of VL, array & enum super datatype */
     H5T_t       *new_type = NULL;   /* New native datatype */
@@ -218,26 +217,36 @@ H5T__get_native_type(H5T_t *dtype, H5T_direction_t direction, size_t *struct_ali
 
         case H5T_REFERENCE:
             {
+                H5T_t *dt;          /* Datatype to make native */
                 size_t align;
                 size_t ref_size;
-                int    not_equal;
 
                 if(NULL == (ret_value = H5T_copy(dtype, H5T_COPY_TRANSIENT)))
-                    HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "cannot retrieve float type")
+                    HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "cannot copy reference type")
 
-                /* Decide if the data type is object or dataset region reference. */
+                /* Decide if the data type is object reference. */
                 if(NULL == (dt = (H5T_t *)H5I_object(H5T_STD_REF_OBJ_g)))
                     HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a data type")
-                not_equal = H5T_cmp(ret_value, dt, FALSE);
 
                 /* Update size, offset and compound alignment for parent. */
-                if(!not_equal) {
+                if(0 == H5T_cmp(ret_value, dt, FALSE)) {
                     align = H5T_HOBJREF_COMP_ALIGN_g;
                     ref_size = sizeof(hobj_ref_t);
                 } /* end if */
                 else {
-                    align = H5T_HDSETREGREF_COMP_ALIGN_g;
-                    ref_size = sizeof(hdset_reg_ref_t);
+                    /* Decide if the data type is dataset region reference. */
+                    if(NULL == (dt = (H5T_t *)H5I_object(H5T_STD_REF_DSETREG_g)))
+                        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a data type")
+
+                    if (0 == H5T_cmp(ret_value, dt, FALSE)) {
+                        align = H5T_HDSETREGREF_COMP_ALIGN_g;
+                        ref_size = sizeof(hdset_reg_ref_t);
+                    } /* end if */
+                    else {
+                        /* Only pointers to underlying opaque reference types */
+                        align = H5T_REF_COMP_ALIGN_g;
+                        ref_size = sizeof(H5R_ref_t);
+                    } /* end else */
                 } /* end else */
 
                 if(H5T__cmp_offset(comp_size, offset, ref_size, (size_t)1, align, struct_align) < 0)
diff --git a/src/H5Tpkg.h b/src/H5Tpkg.h
index 281026c..9784abd 100644
--- a/src/H5Tpkg.h
+++ b/src/H5Tpkg.h
@@ -95,9 +95,14 @@
 /* This version also encodes array types more efficiently */
 #define H5O_DTYPE_VERSION_3	3
 
+/* This is the version that adds support for new reference types and prevents
+ * older versions of the library to attempt reading unknown types.
+ */
+#define H5O_DTYPE_VERSION_4 4
+
 /* The latest version of the format.  Look through the 'encode helper' routine
  *      and 'size' callback for places to change when updating this. */
-#define H5O_DTYPE_VERSION_LATEST H5O_DTYPE_VERSION_3
+#define H5O_DTYPE_VERSION_LATEST H5O_DTYPE_VERSION_4
 
 
 /* Flags for visiting datatype */
@@ -175,37 +180,52 @@ struct H5T_path_t {
     H5T_cdata_t	cdata;			/*data for this function	     */
 };
 
+/* Reference function pointers */
+typedef size_t (*H5T_ref_getsizefunc_t)(H5F_t *src_f, const void *src_buf, size_t src_size, H5F_t *dst_f, hbool_t *dst_copy);
+typedef herr_t (*H5T_ref_readfunc_t)(H5F_t *src_f, const void *src_buf, size_t src_size, H5F_t *dst_f, void *dst_buf, size_t dst_size);
+typedef herr_t (*H5T_ref_writefunc_t)(H5F_t *src_f, const void *src_buf, size_t src_size, H5R_type_t src_type, H5F_t *dst_f, void *dst_buf, size_t dst_size, void *bg_buf);
+
+typedef struct H5T_ref_class_t {
+    H5T_ref_getsizefunc_t   getsize;    /* get reference size (bytes)   */
+    H5T_ref_readfunc_t      read;       /* read reference into buffer   */
+    H5T_ref_writefunc_t     write;      /* write reference from buffer  */
+} H5T_ref_class_t;
+
 typedef struct H5T_atomic_t {
-    H5T_order_t		order;	/*byte order				     */
-    size_t		prec;	/*precision in bits			     */
-    size_t		offset; /*bit position of lsb of value		     */
-    H5T_pad_t	        lsb_pad;/*type of lsb padding			     */
-    H5T_pad_t		msb_pad;/*type of msb padding			     */
+    H5T_order_t order;              /* byte order                           */
+    size_t      prec;               /* precision in bits                    */
+    size_t      offset;             /* bit position of lsb of value         */
+    H5T_pad_t   lsb_pad;            /* type of lsb padding                  */
+    H5T_pad_t   msb_pad;            /* type of msb padding                  */
     union {
-	struct {
-	    H5T_sign_t	sign;	/*type of integer sign			     */
-	} i;			/*integer; integer types		     */
-
-	struct {
-	    size_t	sign;	/*bit position of sign bit		     */
-	    size_t	epos;	/*position of lsb of exponent		     */
-	    size_t	esize;	/*size of exponent in bits		     */
-	    uint64_t	ebias;	/*exponent bias				     */
-	    size_t	mpos;	/*position of lsb of mantissa		     */
-	    size_t	msize;	/*size of mantissa			     */
-	    H5T_norm_t	norm;	/*normalization				     */
-	    H5T_pad_t	pad;	/*type of padding for internal bits	     */
-	} f;			/*floating-point types			     */
-
-	struct {
-	    H5T_cset_t	cset;	/*character set				     */
-	    H5T_str_t	pad;	/*space or null padding of extra bytes	     */
-	} s;			/*string types				     */
-
-	struct {
-	    H5R_type_t	rtype;	/*type of reference stored		     */
-            H5T_loc_t   loc;    /* Location of data in buffer		     */
-	} r;			/*reference types			     */
+        struct {
+            H5T_sign_t  sign;       /* type of integer sign                 */
+        } i;    /* integer; integer types */
+
+        struct {
+            size_t      sign;       /* bit position of sign bit             */
+            size_t      epos;       /* position of lsb of exponent          */
+            size_t      esize;      /* size of exponent in bits             */
+            uint64_t    ebias;      /* exponent bias                        */
+            size_t      mpos;       /* position of lsb of mantissa          */
+            size_t      msize;      /* size of mantissa                     */
+            H5T_norm_t  norm;       /* normalization                        */
+            H5T_pad_t   pad;        /* type of padding for internal bits    */
+        } f;    /* floating-point types */
+
+        struct {
+            H5T_cset_t  cset;       /* character set                        */
+            H5T_str_t   pad;        /* space or null padding of extra bytes */
+        } s;    /* string types */
+
+        struct {
+            H5R_type_t  rtype;      /* type of reference stored             */
+            unsigned    version;    /* version of encoded reference         */
+            hbool_t     opaque;     /* opaque reference type                */
+            H5T_loc_t   loc;        /* location of data in buffer           */
+            H5F_t       *f;         /* file pointer (if data is on disk)    */
+            const H5T_ref_class_t *cls; /* Pointer to ref class callbacks */
+        } r;    /* reference types */
     } u;
 } H5T_atomic_t;
 
@@ -378,6 +398,7 @@ H5_DLLVAR size_t H5T_POINTER_COMP_ALIGN_g;
 H5_DLLVAR size_t H5T_HVL_COMP_ALIGN_g;
 H5_DLLVAR size_t H5T_HOBJREF_COMP_ALIGN_g;
 H5_DLLVAR size_t H5T_HDSETREGREF_COMP_ALIGN_g;
+H5_DLLVAR size_t H5T_REF_COMP_ALIGN_g;
 
 /*
  * Alignment information for native types. A value of N indicates that the
@@ -490,6 +511,9 @@ H5_DLL herr_t H5T__conv_vlen(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 H5_DLL herr_t H5T__conv_array(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 			    size_t nelmts, size_t buf_stride,
                             size_t bkg_stride, void *buf, void *bkg);
+H5_DLL herr_t H5T__conv_ref(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
+                            size_t nelmts, size_t buf_stride,
+                            size_t bkg_stride, void *buf, void *bkg);
 H5_DLL herr_t H5T__conv_i_i(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
                             size_t nelmts, size_t buf_stride,
                             size_t bkg_stride, void *_buf, void *bkg);
@@ -1156,6 +1180,9 @@ H5_DLL H5T_t *H5T__array_create(H5T_t *base, unsigned ndims, const hsize_t dim[/
 H5_DLL int    H5T__get_array_ndims(const H5T_t *dt);
 H5_DLL int    H5T__get_array_dims(const H5T_t *dt, hsize_t dims[]);
 
+/* Reference functions */
+H5_DLL htri_t H5T__ref_set_loc(const H5T_t *dt, H5F_t *f, H5T_loc_t loc);
+
 /* Compound functions */
 H5_DLL herr_t H5T__insert(H5T_t *parent, const char *name, size_t offset,
         const H5T_t *member);
diff --git a/src/H5Tprivate.h b/src/H5Tprivate.h
index 3dcbb2c..13a0938 100644
--- a/src/H5Tprivate.h
+++ b/src/H5Tprivate.h
@@ -52,6 +52,9 @@ typedef struct H5T_t H5T_t;
 typedef struct H5T_stats_t H5T_stats_t;
 typedef struct H5T_path_t H5T_path_t;
 
+/* Forward reference of H5S_t */
+struct H5S_t;
+
 /* How to copy a datatype */
 typedef enum H5T_copy_t {
     H5T_COPY_TRANSIENT,
@@ -130,7 +133,10 @@ H5_DLL H5T_bkg_t H5T_path_bkg(const H5T_path_t *p);
 H5_DLL H5T_subset_info_t *H5T_path_compound_subset(const H5T_path_t *p);
 H5_DLL herr_t H5T_convert(H5T_path_t *tpath, hid_t src_id, hid_t dst_id,
     size_t nelmts, size_t buf_stride, size_t bkg_stride, void *buf, void *bkg);
-H5_DLL herr_t H5T_vlen_reclaim(void *elem, hid_t type_id, unsigned ndim, const hsize_t *point, void *_op_data);
+H5_DLL herr_t H5T_reclaim(hid_t type_id, struct H5S_t *space, void *buf);
+H5_DLL herr_t H5T_reclaim_cb(void *elem, const H5T_t *dt, unsigned ndim, const hsize_t *point, void *op_data);
+H5_DLL herr_t H5T_ref_reclaim(void *elem, const H5T_t *dt);
+H5_DLL herr_t H5T_vlen_reclaim(void *elem, const H5T_t *dt, H5T_vlen_alloc_info_t *alloc_info);
 H5_DLL herr_t H5T_vlen_reclaim_elmt(void *elem, H5T_t *dt);
 H5_DLL htri_t H5T_set_loc(H5T_t *dt, H5F_t *f, H5T_loc_t loc);
 H5_DLL htri_t H5T_is_sensible(const H5T_t *dt);
diff --git a/src/H5Tpublic.h b/src/H5Tpublic.h
index fc3e4ee..0ec0c73 100644
--- a/src/H5Tpublic.h
+++ b/src/H5Tpublic.h
@@ -262,8 +262,9 @@ H5_DLLVAR hid_t H5T_IEEE_F64LE_g;
 #define H5T_STD_B32LE		(H5OPEN H5T_STD_B32LE_g)
 #define H5T_STD_B64BE		(H5OPEN H5T_STD_B64BE_g)
 #define H5T_STD_B64LE		(H5OPEN H5T_STD_B64LE_g)
-#define H5T_STD_REF_OBJ	        (H5OPEN H5T_STD_REF_OBJ_g)
+#define H5T_STD_REF_OBJ         (H5OPEN H5T_STD_REF_OBJ_g)
 #define H5T_STD_REF_DSETREG     (H5OPEN H5T_STD_REF_DSETREG_g)
+#define H5T_STD_REF             (H5OPEN H5T_STD_REF_g)
 H5_DLLVAR hid_t H5T_STD_I8BE_g;
 H5_DLLVAR hid_t H5T_STD_I8LE_g;
 H5_DLLVAR hid_t H5T_STD_I16BE_g;
@@ -290,6 +291,7 @@ H5_DLLVAR hid_t H5T_STD_B64BE_g;
 H5_DLLVAR hid_t H5T_STD_B64LE_g;
 H5_DLLVAR hid_t H5T_STD_REF_OBJ_g;
 H5_DLLVAR hid_t H5T_STD_REF_DSETREG_g;
+H5_DLLVAR hid_t H5T_STD_REF_g;
 
 /*
  * Types which are particular to Unix.
@@ -591,6 +593,7 @@ H5_DLL H5T_conv_t H5Tfind(hid_t src_id, hid_t dst_id, H5T_cdata_t **pcdata);
 H5_DLL htri_t H5Tcompiler_conv(hid_t src_id, hid_t dst_id);
 H5_DLL herr_t H5Tconvert(hid_t src_id, hid_t dst_id, size_t nelmts,
 			  void *buf, void *background, hid_t plist_id);
+H5_DLL herr_t H5Treclaim(hid_t type_id, hid_t space_id, hid_t plist_id, void *buf);
 
 /* Symbols defined for compatibility with previous versions of the HDF5 API.
  *
diff --git a/src/H5Tref.c b/src/H5Tref.c
new file mode 100644
index 0000000..6f7bf90
--- /dev/null
+++ b/src/H5Tref.c
@@ -0,0 +1,761 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the COPYING file, which can be found at the root of the source code       *
+ * distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.  *
+ * If you do not have access to either file, you may request a copy from     *
+ * help@hdfgroup.org.                                                        *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*
+ * Module Info: This module contains the functionality for reference
+ *      datatypes in the H5T interface.
+ */
+
+#include "H5Tmodule.h"          /* This source code file is part of the H5T module */
+#define H5F_FRIEND              /*suppress error about including H5Fpkg   */
+#define H5R_FRIEND              /*suppress error about including H5Rpkg   */
+
+#include "H5private.h"          /* Generic Functions    */
+#include "H5CXprivate.h"        /* API Contexts         */
+#include "H5Eprivate.h"         /* Error handling       */
+#include "H5Iprivate.h"         /* IDs                  */
+#include "H5Fpkg.h"             /* File                 */
+#include "H5Rpkg.h"             /* References           */
+#include "H5Tpkg.h"             /* Datatypes            */
+
+/****************/
+/* Local Macros */
+/****************/
+
+#define H5T_REF_MEM_SIZE                (H5R_REF_BUF_SIZE)
+#define H5T_REF_OBJ_MEM_SIZE            (H5R_OBJ_REF_BUF_SIZE)
+#define H5T_REF_DSETREG_MEM_SIZE        (H5R_DSET_REG_REF_BUF_SIZE)
+
+#define H5T_REF_OBJ_DISK_SIZE(f)        (H5F_SIZEOF_ADDR(f))
+#define H5T_REF_DSETREG_DISK_SIZE(f)    (H5HG_HEAP_ID_SIZE(f))
+
+/******************/
+/* Local Typedefs */
+/******************/
+
+/* For region compatibility support */
+struct H5Tref_dsetreg {
+    haddr_t obj_addr;   /* Object address */
+    H5S_t *space;       /* Dataspace */
+};
+
+/********************/
+/* Local Prototypes */
+/********************/
+
+static size_t H5T__ref_mem_getsize(H5F_t *src_f, const void *src_buf, size_t src_size, H5F_t *dst_f, hbool_t *dst_copy);
+static herr_t H5T__ref_mem_read(H5F_t *src_f, const void *src_buf, size_t src_size, H5F_t *dst_f, void *dst_buf, size_t dst_size);
+static herr_t H5T__ref_mem_write(H5F_t *src_f, const void *src_buf, size_t src_size, H5R_type_t src_type, H5F_t *dst_f, void *dst_buf, size_t dst_size, void *bg_buf);
+
+static size_t H5T__ref_disk_getsize(H5F_t *src_f, const void *src_buf, size_t src_size, H5F_t *dst_f, hbool_t *dst_copy);
+static herr_t H5T__ref_disk_read(H5F_t *src_f, const void *src_buf, size_t src_size, H5F_t *dst_f, void *dst_buf, size_t dst_size);
+static herr_t H5T__ref_disk_write(H5F_t *src_f, const void *src_buf, size_t src_size, H5R_type_t src_type, H5F_t *dst_f, void *dst_buf, size_t dst_size, void *bg_buf);
+
+/* For compatibility */
+static size_t H5T__ref_obj_disk_getsize(H5F_t *src_f, const void *src_buf, size_t src_size, H5F_t *dst_f, hbool_t *dst_copy);
+static herr_t H5T__ref_obj_disk_read(H5F_t *src_f, const void *src_buf, size_t src_size, H5F_t *dst_f, void *dst_buf, size_t dst_size);
+
+static size_t H5T__ref_dsetreg_disk_getsize(H5F_t *src_f, const void *src_buf, size_t src_size, H5F_t *dst_f, hbool_t *dst_copy);
+static herr_t H5T__ref_dsetreg_disk_read(H5F_t *src_f, const void *src_buf, size_t src_size, H5F_t *dst_f, void *dst_buf, size_t dst_size);
+
+/*******************/
+/* Local Variables */
+/*******************/
+
+/* Class for reference in memory */
+static const H5T_ref_class_t H5T_ref_mem_g = {
+    H5T__ref_mem_getsize,           /* 'getsize' */
+    H5T__ref_mem_read,              /* 'read' */
+    H5T__ref_mem_write              /* 'write' */
+};
+
+static const H5T_ref_class_t H5T_ref_disk_g = {
+    H5T__ref_disk_getsize,          /* 'getsize' */
+    H5T__ref_disk_read,             /* 'read' */
+    H5T__ref_disk_write             /* 'write' */
+};
+
+static const H5T_ref_class_t H5T_ref_obj_disk_g = {
+    H5T__ref_obj_disk_getsize,      /* 'getsize' */
+    H5T__ref_obj_disk_read,         /* 'read' */
+    NULL                            /* 'write' */
+};
+
+static const H5T_ref_class_t H5T_ref_dsetreg_disk_g = {
+    H5T__ref_dsetreg_disk_getsize,  /* 'getsize' */
+    H5T__ref_dsetreg_disk_read,     /* 'read' */
+    NULL                            /* 'write' */
+};
+
+
+/*-------------------------------------------------------------------------
+ * Function: H5T__ref_set_loc
+ *
+ * Purpose:	Sets the location of a reference datatype to be either on disk
+ *          or in memory
+ *
+ * Return:
+ *  One of two values on success:
+ *      TRUE - If the location of any reference types changed
+ *      FALSE - If the location of any reference types is the same
+ *  Negative value is returned on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+htri_t
+H5T__ref_set_loc(const H5T_t *dt, H5F_t *f, H5T_loc_t loc)
+{
+    htri_t ret_value = FALSE; /* Indicate success, but no location change */
+
+    FUNC_ENTER_PACKAGE
+
+    HDassert(dt);
+    /* f is NULL when loc == H5T_LOC_MEMORY */
+    HDassert(loc >= H5T_LOC_BADLOC && loc < H5T_LOC_MAXLOC);
+
+    /* Only change the location if it's different */
+    if(loc == dt->shared->u.atomic.u.r.loc && f == dt->shared->u.atomic.u.r.f)
+        HGOTO_DONE(FALSE)
+
+    switch(loc) {
+        case H5T_LOC_MEMORY: /* Memory based reference datatype */
+            HDassert(NULL == f);
+
+            /* Mark this type as being stored in memory */
+            dt->shared->u.atomic.u.r.loc = H5T_LOC_MEMORY;
+
+            /* Reset file ID (since this reference is in memory) */
+            dt->shared->u.atomic.u.r.f = f;     /* f is NULL */
+
+            if(dt->shared->u.atomic.u.r.opaque) {
+                /* Size in memory, disk size is different */
+                dt->shared->size = H5T_REF_MEM_SIZE;
+                dt->shared->u.atomic.prec = 8 * dt->shared->size;
+
+                /* Set up the function pointers to access the reference in memory */
+                dt->shared->u.atomic.u.r.cls = &H5T_ref_mem_g;
+
+            } else if(dt->shared->u.atomic.u.r.rtype == H5R_OBJECT1) {
+                /* Size in memory, disk size is different */
+                dt->shared->size = H5T_REF_OBJ_MEM_SIZE;
+                dt->shared->u.atomic.prec = 8 * dt->shared->size;
+
+                /* Unused for now */
+                dt->shared->u.atomic.u.r.cls = NULL;
+
+            } else if(dt->shared->u.atomic.u.r.rtype == H5R_DATASET_REGION1) {
+                /* Size in memory, disk size is different */
+                dt->shared->size = H5T_REF_DSETREG_MEM_SIZE;
+                dt->shared->u.atomic.prec = 8 * dt->shared->size;
+
+                /* Unused for now */
+                dt->shared->u.atomic.u.r.cls = NULL;
+
+            }
+            break;
+
+        case H5T_LOC_DISK: /* Disk based reference datatype */
+            HDassert(f);
+
+            /* Mark this type as being stored on disk */
+            dt->shared->u.atomic.u.r.loc = H5T_LOC_DISK;
+
+            /* Set file pointer (since this reference is on disk) */
+            dt->shared->u.atomic.u.r.f = f;
+
+            if(dt->shared->u.atomic.u.r.rtype == H5R_OBJECT1) {
+                /* Size on disk, memory size is different */
+                dt->shared->size = H5T_REF_OBJ_DISK_SIZE(f);
+                dt->shared->u.atomic.prec = 8 * dt->shared->size;
+
+                /* Set up the function pointers to access the reference in memory */
+                dt->shared->u.atomic.u.r.cls = &H5T_ref_obj_disk_g;
+
+            } else if(dt->shared->u.atomic.u.r.rtype == H5R_DATASET_REGION1) {
+                /* Size on disk, memory size is different */
+                dt->shared->size = H5T_REF_DSETREG_DISK_SIZE(f);
+                dt->shared->u.atomic.prec = 8 * dt->shared->size;
+
+                /* Set up the function pointers to access the reference in memory */
+                dt->shared->u.atomic.u.r.cls = &H5T_ref_dsetreg_disk_g;
+
+            } else {
+                H5VL_file_cont_info_t cont_info = {H5VL_CONTAINER_INFO_VERSION, 0, 0, 0};
+                size_t ref_encode_size;
+                H5R_ref_priv_t fixed_ref;
+
+                /* Get container info */
+                if(H5F__get_cont_info(f, &cont_info) < 0)
+                    HGOTO_ERROR(H5E_DATATYPE, H5E_CANTGET, FAIL, "can't get file container info")
+
+                /* Retrieve min encode size (when references have no vlen part) */
+                HDmemset(&fixed_ref, 0, sizeof(fixed_ref));
+                fixed_ref.type = (int8_t)H5R_OBJECT2;
+                fixed_ref.token_size = (uint8_t)cont_info.token_size;
+                if(H5R__encode(NULL, &fixed_ref, NULL, &ref_encode_size, 0) < 0)
+                    HGOTO_ERROR(H5E_REFERENCE, H5E_CANTGET, FAIL, "can't get encode size")
+
+                /* Size on disk, memory size is different */
+                dt->shared->size = MAX(H5_SIZEOF_UINT32_T +
+                    H5R_ENCODE_HEADER_SIZE + cont_info.blob_id_size,
+                    ref_encode_size);
+                dt->shared->u.atomic.prec = 8 * dt->shared->size;
+
+                /* Set up the function pointers to access the information on
+                 * disk. Region and attribute references are stored identically
+                 * on disk, so use the same functions.
+                 */
+                dt->shared->u.atomic.u.r.cls = &H5T_ref_disk_g;
+
+            }
+            break;
+
+        case H5T_LOC_BADLOC:
+            /* Allow undefined location. In H5Odtype.c, H5O_dtype_decode sets undefined
+             * location for reference type and leaves it for the caller to decide.
+             */
+            dt->shared->u.atomic.u.r.loc = H5T_LOC_BADLOC;
+
+            /* Reset file pointer */
+            dt->shared->u.atomic.u.r.f = NULL;
+
+            /* Reset the function pointers */
+            dt->shared->u.atomic.u.r.cls = NULL;
+
+            break;
+
+        case H5T_LOC_MAXLOC:
+            /* MAXLOC is invalid */
+        default:
+            HGOTO_ERROR(H5E_DATATYPE, H5E_BADRANGE, FAIL, "invalid reference datatype location")
+    } /* end switch */
+
+    /* Indicate that the location changed */
+    ret_value = TRUE;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T__ref_set_loc() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5T__ref_mem_getsize
+ *
+ * Purpose:	Retrieves the size of a memory based reference.
+ *
+ * Return:	Non-negative on success/zero on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static size_t
+H5T__ref_mem_getsize(H5F_t H5_ATTR_UNUSED *src_f, const void *src_buf,
+    size_t H5_ATTR_UNUSED src_size, H5F_t *dst_f, hbool_t *dst_copy)
+{
+    void *vol_obj = NULL;
+    const H5R_ref_priv_t *src_ref = (const H5R_ref_priv_t *)src_buf;
+    unsigned flags = 0;
+    size_t ret_value = 0;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(src_buf);
+    HDassert(src_size == H5T_REF_MEM_SIZE);
+
+    /* Retrieve VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(src_ref->loc_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "invalid location identifier")
+
+    /* Retrieve file from VOL object */
+    if(NULL == (src_f = (H5F_t *)H5VL_object_data(vol_obj)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "invalid VOL object")
+
+    /* Set external flag if referenced file is not destination file */
+    flags |= (src_f->shared != dst_f->shared) ? H5R_IS_EXTERNAL : 0;
+
+    /* Force re-calculating encoding size if any flags are set */
+    if(flags || !src_ref->encode_size) {
+        /* Pass the correct encoding version for the selection depending on the
+         * file libver bounds, this is later retrieved in H5S hyper encode */
+        if(src_ref->type == (int8_t)H5R_DATASET_REGION2)
+            H5CX_set_libver_bounds(dst_f);
+
+        /* Determine encoding size */
+        if(H5R__encode(H5F_ACTUAL_NAME(src_f), src_ref, NULL, &ret_value, flags) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTENCODE, 0, "unable to determine encoding size")
+    } else {
+        /* Can do a direct copy and skip blob decoding */
+        if(src_ref->type == (int8_t)H5R_OBJECT2)
+            *dst_copy = TRUE;
+
+        /* Get cached encoding size */
+        ret_value = src_ref->encode_size;
+    }
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T__ref_mem_getsize() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5T__ref_mem_read
+ *
+ * Purpose:	"Reads" the memory based reference into a buffer
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5T__ref_mem_read(H5F_t H5_ATTR_UNUSED *src_f, const void *src_buf,
+    size_t H5_ATTR_UNUSED src_size, H5F_t *dst_f, void *dst_buf,
+    size_t dst_size)
+{
+    void *vol_obj = NULL;
+    const H5R_ref_priv_t *src_ref = (const H5R_ref_priv_t *)src_buf;
+    unsigned flags = 0;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(src_buf);
+    HDassert(src_size == H5T_REF_MEM_SIZE);
+    HDassert(dst_f);
+    HDassert(dst_buf);
+    HDassert(dst_size);
+
+    /* Retrieve VOL object */
+    if(NULL == (vol_obj = H5VL_vol_object(src_ref->loc_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "invalid location identifier")
+
+    /* Retrieve file from VOL object */
+    if(NULL == (src_f = (H5F_t *)H5VL_object_data(vol_obj)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "invalid VOL object")
+
+    /* Set external flag if referenced file is not destination file */
+    flags |= (src_f->shared != dst_f->shared) ? H5R_IS_EXTERNAL : 0;
+
+    /* Pass the correct encoding version for the selection depending on the
+     * file libver bounds, this is later retrieved in H5S hyper encode */
+    if(src_ref->type == (int8_t)H5R_DATASET_REGION2)
+        H5CX_set_libver_bounds(dst_f);
+
+    /* Encode reference */
+    if(H5R__encode(H5F_ACTUAL_NAME(src_f), src_ref, dst_buf, &dst_size, flags) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTENCODE, FAIL, "Cannot encode reference")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T__ref_mem_read() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5T__ref_mem_write
+ *
+ * Purpose:	"Writes" the memory reference from a buffer
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5T__ref_mem_write(H5F_t *src_f, const void *src_buf, size_t src_size,
+    H5R_type_t src_type, H5F_t H5_ATTR_UNUSED *dst_f, void *dst_buf,
+    size_t dst_size, void H5_ATTR_UNUSED *bg_buf)
+{
+    hid_t file_id = H5I_INVALID_HID;
+    H5R_ref_priv_t *dst_ref = (H5R_ref_priv_t *)dst_buf;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(src_f);
+    HDassert(src_buf);
+    HDassert(src_size);
+    HDassert(dst_buf);
+    HDassert(dst_size == H5T_REF_MEM_SIZE);
+
+    /* Make sure reference buffer is correctly initialized */
+    HDmemset(dst_buf, 0, dst_size);
+
+    switch(src_type) {
+        case H5R_OBJECT1: {
+            if(H5R__create_object((const H5VL_token_t *)src_buf, sizeof(haddr_t), dst_ref) < 0)
+                HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCREATE, FAIL, "unable to create object reference")
+        }
+            break;
+        case H5R_DATASET_REGION1: {
+            const struct H5Tref_dsetreg *src_reg = (const struct H5Tref_dsetreg *)src_buf;
+
+            if(H5R__create_region((const H5VL_token_t *)&src_reg->obj_addr, sizeof(src_reg->obj_addr), src_reg->space, dst_ref) < 0)
+                HGOTO_ERROR(H5E_REFERENCE, H5E_CANTCREATE, FAIL, "unable to create region reference")
+            /* create_region creates its internal copy of the space */
+            if(H5S_close(src_reg->space) < 0)
+                HGOTO_ERROR(H5E_REFERENCE, H5E_CANTFREE, FAIL, "Cannot close dataspace")
+        }
+            break;
+        case H5R_DATASET_REGION2:
+            /* Pass the correct encoding version for the selection depending on the
+             * file libver bounds, this is later retrieved in H5S hyper decode */
+            H5CX_set_libver_bounds(src_f);
+            H5_ATTR_FALLTHROUGH
+        case H5R_OBJECT2:
+        case H5R_ATTR:
+            /* Decode reference */
+            if(H5R__decode((const unsigned char *)src_buf, &src_size, dst_ref) < 0)
+                HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Cannot decode reference")
+            break;
+        case H5R_BADTYPE:
+        case H5R_MAXTYPE:
+        default:
+            HDassert("unknown reference type" && 0);
+            HGOTO_ERROR(H5E_REFERENCE, H5E_UNSUPPORTED, FAIL, "internal error (unknown reference type)")
+    }
+
+    /* If no filename set, this is not an external reference */
+    if(NULL == H5R_REF_FILENAME(dst_ref)) {
+        /* TODO temporary hack to retrieve file object */
+        if((file_id = H5F__get_file_id(src_f, FALSE)) < 0)
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file or file object")
+
+        /* Attach loc ID to reference and hold reference to it */
+        if(H5R__set_loc_id(dst_ref, file_id, TRUE) < 0)
+            HGOTO_ERROR(H5E_REFERENCE, H5E_CANTSET, FAIL, "unable to attach location id to reference")
+    }
+
+done:
+    if((file_id != H5I_INVALID_HID) && (H5I_dec_ref(file_id) < 0))
+        HDONE_ERROR(H5E_REFERENCE, H5E_CANTDEC, FAIL, "unable to decrement refcount on location id")
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T__ref_mem_write() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5T__ref_disk_getsize
+ *
+ * Purpose:	Retrieves the length of a disk based reference.
+ *
+ * Return:	Non-negative value (cannot fail)
+ *
+ *-------------------------------------------------------------------------
+ */
+static size_t
+H5T__ref_disk_getsize(H5F_t H5_ATTR_UNUSED *src_f, const void *src_buf,
+    size_t src_size, H5F_t H5_ATTR_UNUSED *dst_f, hbool_t *dst_copy)
+{
+    const uint8_t *p = (const uint8_t *)src_buf;
+    unsigned flags;
+    H5R_type_t ref_type;
+    size_t ret_value = 0;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(src_buf);
+
+    /* Set reference type */
+    ref_type = (H5R_type_t)*p++;
+    if(ref_type <= H5R_BADTYPE || ref_type >= H5R_MAXTYPE)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, 0, "invalid reference type")
+
+    /* Set flags */
+    flags = (unsigned)*p++;
+
+    if(!(flags & H5R_IS_EXTERNAL) && (ref_type == H5R_OBJECT2)) {
+        /* Can do a direct copy and skip blob decoding */
+        *dst_copy = TRUE;
+
+        ret_value = src_size;
+    } else {
+        /* Retrieve encoded data size */
+        UINT32DECODE(p, ret_value);
+
+        /* Add size of the header */
+        ret_value += H5R_ENCODE_HEADER_SIZE;
+    }
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T__ref_disk_getsize() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5T__ref_disk_read
+ *
+ * Purpose:	Reads the disk based reference into a buffer
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5T__ref_disk_read(H5F_t *src_f, const void *src_buf, size_t src_size,
+    H5F_t H5_ATTR_UNUSED *dst_f, void *dst_buf, size_t dst_size)
+{
+    H5VL_object_t *vol_obj = NULL;  /* Object info */
+    hid_t file_id = H5I_INVALID_HID;
+    const uint8_t *p = (const uint8_t *)src_buf;
+    uint8_t *q = (uint8_t *)dst_buf;
+    size_t buf_size_left = src_size;
+    size_t expected_size = dst_size;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(src_f);
+    HDassert(src_buf);
+    HDassert(dst_buf);
+    HDassert(dst_size);
+
+    /* TODO temporary hack to retrieve file object */
+    if((file_id = H5F__get_file_id(src_f, FALSE)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file or file object")
+    if(NULL == (vol_obj = H5VL_vol_object(file_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid object identifier")
+
+    /* Copy header manually */
+    HDmemcpy(q, p, H5R_ENCODE_HEADER_SIZE);
+    p += H5R_ENCODE_HEADER_SIZE;
+    q += H5R_ENCODE_HEADER_SIZE;
+    expected_size -= H5R_ENCODE_HEADER_SIZE;
+
+    /* Skip the length of the sequence */
+    p += H5_SIZEOF_UINT32_T;
+    HDassert(buf_size_left > H5_SIZEOF_UINT32_T);
+    buf_size_left -= H5_SIZEOF_UINT32_T;
+
+    /* Retrieve blob */
+    if(H5VL_blob_get(vol_obj, p, q, &dst_size, NULL) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTGET, FAIL, "unable to get blob")
+    if(dst_size != expected_size)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "Expected data size does not match")
+
+done:
+    if((file_id != H5I_INVALID_HID) && (H5I_dec_ref(file_id) < 0))
+        HDONE_ERROR(H5E_DATATYPE, H5E_CANTDEC, FAIL, "unable to decrement refcount on file id")
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T__ref_disk_read() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5T__ref_disk_write
+ *
+ * Purpose:	Writes the disk based reference from a buffer
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5T__ref_disk_write(H5F_t H5_ATTR_UNUSED *src_f, const void *src_buf,
+    size_t src_size, H5R_type_t H5_ATTR_UNUSED src_type, H5F_t *dst_f,
+    void *dst_buf, size_t dst_size, void *bg_buf)
+{
+    H5VL_object_t *vol_obj = NULL;  /* Object info */
+    hid_t file_id = H5I_INVALID_HID;
+    const uint8_t *p = (const uint8_t *)src_buf;
+    uint8_t *q = (uint8_t *)dst_buf;
+    size_t buf_size_left = dst_size;
+    uint8_t *p_bg = (uint8_t *)bg_buf;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(src_buf);
+    HDassert(src_size);
+    HDassert(dst_f);
+    HDassert(dst_buf);
+
+    /* TODO temporary hack to retrieve file object */
+    if((file_id = H5F__get_file_id(dst_f, FALSE)) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file or file object")
+    if(NULL == (vol_obj = H5VL_vol_object(file_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid object identifier")
+
+    /* TODO Should get rid of bg stuff */
+    if(p_bg) {
+        size_t p_buf_size_left = dst_size;
+
+        /* Skip the length of the reference */
+        p_bg += H5_SIZEOF_UINT32_T;
+        HDassert(p_buf_size_left > H5_SIZEOF_UINT32_T);
+        p_buf_size_left -= H5_SIZEOF_UINT32_T;
+
+        /* Remove blob for old data */
+        if(H5VL_blob_specific(vol_obj, (void *)p_bg, H5VL_BLOB_DELETE) < 0)
+            HGOTO_ERROR(H5E_DATATYPE, H5E_CANTREMOVE, FAIL, "unable to delete blob")
+    } /* end if */
+
+    /* Copy header manually so that it does not get encoded into the blob */
+    HDmemcpy(q, p, H5R_ENCODE_HEADER_SIZE);
+    p += H5R_ENCODE_HEADER_SIZE;
+    q += H5R_ENCODE_HEADER_SIZE;
+    src_size -= H5R_ENCODE_HEADER_SIZE;
+    buf_size_left -= H5_SIZEOF_UINT32_T;
+
+    /* Set the size */
+    UINT32ENCODE(q, src_size);
+    HDassert(buf_size_left > H5_SIZEOF_UINT32_T);
+    buf_size_left -= H5_SIZEOF_UINT32_T;
+
+    /* Store blob */
+    if(H5VL_blob_put(vol_obj, p, src_size, q, NULL) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTSET, FAIL, "unable to put blob")
+
+done:
+    if((file_id != H5I_INVALID_HID) && (H5I_dec_ref(file_id) < 0))
+        HDONE_ERROR(H5E_DATATYPE, H5E_CANTDEC, FAIL, "unable to decrement refcount on file id")
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T__ref_disk_write() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5T__ref_obj_disk_getsize
+ *
+ * Purpose: Retrieves the length of a disk based reference.
+ *
+ * Return:  Non-negative value (cannot fail)
+ *
+ *-------------------------------------------------------------------------
+ */
+static size_t
+H5T__ref_obj_disk_getsize(H5F_t H5_ATTR_UNUSED *src_f,
+    const void H5_ATTR_UNUSED *src_buf, size_t H5_ATTR_UNUSED src_size,
+    H5F_t H5_ATTR_UNUSED *dst_f, hbool_t H5_ATTR_UNUSED *dst_copy)
+{
+    size_t ret_value = sizeof(haddr_t);
+
+    FUNC_ENTER_STATIC_NOERR
+
+    HDassert(src_buf);
+    HDassert(src_size == H5T_REF_OBJ_DISK_SIZE(src_f));
+
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T__ref_obj_disk_getsize() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5T__ref_obj_disk_read
+ *
+ * Purpose: Reads the disk based reference into a buffer
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5T__ref_obj_disk_read(H5F_t H5_ATTR_UNUSED *src_f, const void *src_buf,
+    size_t src_size, H5F_t H5_ATTR_UNUSED *dst_f, void *dst_buf,
+    size_t H5_ATTR_UNUSED dst_size)
+{
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(src_f);
+    HDassert(src_buf);
+    HDassert(src_size == H5T_REF_OBJ_DISK_SIZE(src_f));
+    HDassert(dst_buf);
+    HDassert(dst_size == sizeof(haddr_t));
+
+    /* Get object address */
+    if(H5R__decode_addr_obj_compat((const unsigned char *)src_buf, &src_size, (haddr_t *)dst_buf) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, H5I_INVALID_HID, "unable to get object address")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T__ref_obj_disk_read() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5T__ref_dsetreg_disk_getsize
+ *
+ * Purpose: Retrieves the length of a disk based reference.
+ *
+ * Return:  Non-negative value (cannot fail)
+ *
+ *-------------------------------------------------------------------------
+ */
+static size_t
+H5T__ref_dsetreg_disk_getsize(H5F_t H5_ATTR_UNUSED *f,
+    const void H5_ATTR_UNUSED *buf, size_t H5_ATTR_UNUSED buf_size,
+    H5F_t H5_ATTR_UNUSED *dst_f, hbool_t H5_ATTR_UNUSED *dst_copy)
+{
+    size_t ret_value = sizeof(struct H5Tref_dsetreg);
+
+    FUNC_ENTER_STATIC_NOERR
+
+    HDassert(buf);
+    HDassert(buf_size == H5T_REF_DSETREG_DISK_SIZE(f));
+
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T__ref_dsetreg_disk_getsize() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5T__ref_dsetreg_disk_read
+ *
+ * Purpose: Reads the disk based reference into a buffer
+ *
+ * Return:  Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5T__ref_dsetreg_disk_read(H5F_t *src_f, const void *src_buf, size_t src_size,
+    H5F_t H5_ATTR_UNUSED *dst_f, void *dst_buf, size_t H5_ATTR_UNUSED dst_size)
+{
+    struct H5Tref_dsetreg *dst_reg = (struct H5Tref_dsetreg *)dst_buf;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    HDassert(src_f);
+    HDassert(src_buf);
+    HDassert(src_size == H5T_REF_DSETREG_DISK_SIZE(src_f));
+    HDassert(dst_buf);
+    HDassert(dst_size == sizeof(struct H5Tref_dsetreg));
+
+    /* Retrieve object address and space */
+    if(H5R__decode_addr_region_compat(src_f, (const unsigned char *)src_buf, &src_size, &dst_reg->obj_addr, &dst_reg->space) < 0)
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTDECODE, FAIL, "unable to get object address")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+}   /* end H5T__ref_dsetreg_disk_read() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5T_ref_reclaim
+ *
+ * Purpose: Internal routine to free reference datatypes
+ *
+ * Return:  Non-negative on success / Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5T_ref_reclaim(void *elem, const H5T_t *dt)
+{
+    herr_t ret_value = SUCCEED;     /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(elem);
+    HDassert(dt && (dt->shared->type == H5T_REFERENCE));
+
+    if(dt->shared->u.atomic.u.r.opaque
+        && (H5R__destroy((H5R_ref_priv_t *)elem) < 0))
+        HGOTO_ERROR(H5E_REFERENCE, H5E_CANTFREE, FAIL, "cannot free reference")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5T_ref_reclaim() */
diff --git a/src/H5Tvlen.c b/src/H5Tvlen.c
index 9f82340..0253b01 100644
--- a/src/H5Tvlen.c
+++ b/src/H5Tvlen.c
@@ -26,15 +26,13 @@
 /***********/
 /* Headers */
 /***********/
-#include "H5private.h"		/* Generic Functions			*/
-#include "H5CXprivate.h"        /* API Contexts                         */
-#include "H5Eprivate.h"		/* Error handling		  	*/
-#include "H5Fprivate.h"         /* File access				*/
+#include "H5private.h"          /* Generic Functions    */
+#include "H5CXprivate.h"        /* API Contexts         */
+#include "H5Eprivate.h"         /* Error handling       */
 #include "H5Fpkg.h"             /* File                 */
-#include "H5Iprivate.h"		/* IDs			  		*/
-#include "H5MMprivate.h"	/* Memory management			*/
-#include "H5Tpkg.h"		/* Datatypes				*/
-
+#include "H5Iprivate.h"         /* IDs                  */
+#include "H5MMprivate.h"        /* Memory management    */
+#include "H5Tpkg.h"             /* Datatypes            */
 
 /****************/
 /* Local Macros */
@@ -54,7 +52,6 @@
 /********************/
 /* Local Prototypes */
 /********************/
-static herr_t H5T__vlen_reclaim_recurse(void *elem, const H5T_t *dt, H5MM_free_t free_func, void *free_info);
 
 /* Memory-based VL sequence callbacks */
 static herr_t H5T__vlen_mem_seq_getlen(H5F_t *f, const void *_vl, size_t *len);
@@ -100,7 +97,7 @@ static herr_t H5T__vlen_disk_delete(H5F_t *f, const void *_vl);
 /* Local Variables */
 /*******************/
 
-/* Class for VL seqences in memory */
+/* Class for VL sequences in memory */
 static const H5T_vlen_class_t H5T_vlen_mem_seq_g = {
     H5T__vlen_mem_seq_getlen,           /* 'getlen' */
     H5T__vlen_mem_seq_getptr,           /* 'getptr' */
@@ -122,7 +119,7 @@ static const H5T_vlen_class_t H5T_vlen_mem_str_g = {
     NULL                                /* 'delete' */
 };
 
-/* Class for both VL strings and seqences in file */
+/* Class for both VL strings and sequences in file */
 static const H5T_vlen_class_t H5T_vlen_disk_g = {
     H5T__vlen_disk_getlen,              /* 'getlen' */
     NULL,                               /* 'getptr' */
@@ -1085,38 +1082,35 @@ done:
 } /* end H5T__vlen_disk_delete() */
 
 
-/*--------------------------------------------------------------------------
- NAME
-    H5T__vlen_reclaim_recurse
- PURPOSE
-    Internal recursive routine to free VL datatypes
- USAGE
-    herr_t H5T__vlen_reclaim_recurse(elem,dt)
-        void *elem;  IN/OUT: Pointer to the dataset element
-        H5T_t *dt;   IN: Datatype of dataset element
-
- RETURNS
-    SUCCEED/FAIL
- DESCRIPTION
-    Frees any dynamic memory used by VL datatypes in the current dataset
-    element.  Performs a recursive depth-first traversal of all compound
-    datatypes to free all VL datatype information allocated by any field.
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
- EXAMPLES
- REVISION LOG
---------------------------------------------------------------------------*/
-static herr_t
-H5T__vlen_reclaim_recurse(void *elem, const H5T_t *dt, H5MM_free_t free_func, void *free_info)
+/*-------------------------------------------------------------------------
+ * Function:    H5T_vlen_reclaim
+ *
+ * Purpose: Internal recursive routine to free VL datatypes
+ *
+ * Return:  Non-negative on success / Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *      Friday, August 15, 2019
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5T_vlen_reclaim(void *elem, const H5T_t *dt, H5T_vlen_alloc_info_t *alloc_info)
 {
     unsigned u;                     /* Local index variable */
+    H5MM_free_t free_func;          /* Free function */
+    void *free_info;                /* Free info */
     herr_t ret_value = SUCCEED;     /* Return value */
 
-    FUNC_ENTER_STATIC
+    FUNC_ENTER_NOAPI(FAIL)
 
     /* Sanity checks */
     HDassert(elem);
     HDassert(dt);
+    HDassert(alloc_info);
+
+    free_func = alloc_info->free_func;
+    free_info = alloc_info->free_info;
 
     /* Check the datatype of this element */
     switch(dt->shared->type) {
@@ -1128,7 +1122,7 @@ H5T__vlen_reclaim_recurse(void *elem, const H5T_t *dt, H5MM_free_t free_func, vo
                 /* Calculate the offset member and recurse on it */
                 for(u = 0; u < dt->shared->u.array.nelem; u++) {
                     off = ((uint8_t *)elem) + u * (dt->shared->parent->shared->size);
-                    if(H5T__vlen_reclaim_recurse(off, dt->shared->parent, free_func, free_info) < 0)
+                    if(H5T_reclaim_cb(off, dt->shared->parent, 0, NULL, alloc_info) < 0)
                         HGOTO_ERROR(H5E_DATATYPE, H5E_CANTFREE, FAIL, "unable to free array element")
                 } /* end for */
             } /* end if */
@@ -1143,7 +1137,7 @@ H5T__vlen_reclaim_recurse(void *elem, const H5T_t *dt, H5MM_free_t free_func, vo
 
                     /* Calculate the offset member and recurse on it */
                     off = ((uint8_t *)elem) + dt->shared->u.compnd.memb[u].offset;
-                    if(H5T__vlen_reclaim_recurse(off, dt->shared->u.compnd.memb[u].type, free_func, free_info) < 0)
+                    if(H5T_reclaim_cb(off, dt->shared->u.compnd.memb[u].type, 0, NULL, alloc_info) < 0)
                         HGOTO_ERROR(H5E_DATATYPE, H5E_CANTFREE, FAIL, "unable to free compound field")
                 } /* end if */
             } /* end for */
@@ -1163,7 +1157,7 @@ H5T__vlen_reclaim_recurse(void *elem, const H5T_t *dt, H5MM_free_t free_func, vo
                         /* Calculate the offset of each array element and recurse on it */
                         while(vl->len > 0) {
                             off = ((uint8_t *)vl->p) + (vl->len - 1) * dt->shared->parent->shared->size;
-                            if(H5T__vlen_reclaim_recurse(off, dt->shared->parent, free_func, free_info) < 0)
+                            if(H5T_reclaim_cb(off, dt->shared->parent, 0, NULL, alloc_info) < 0)
                                 HGOTO_ERROR(H5E_DATATYPE, H5E_CANTFREE, FAIL, "unable to free VL element")
                             vl->len--;
                         } /* end while */
@@ -1193,11 +1187,11 @@ H5T__vlen_reclaim_recurse(void *elem, const H5T_t *dt, H5MM_free_t free_func, vo
         case H5T_STRING:
         case H5T_BITFIELD:
         case H5T_OPAQUE:
-        case H5T_REFERENCE:
         case H5T_ENUM:
             break;
 
         /* Should never have these values */
+        case H5T_REFERENCE:
         case H5T_NO_CLASS:
         case H5T_NCLASSES:
         default:
@@ -1208,58 +1202,6 @@ H5T__vlen_reclaim_recurse(void *elem, const H5T_t *dt, H5MM_free_t free_func, vo
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5T__vlen_reclaim_recurse() */
-
-
-/*--------------------------------------------------------------------------
- NAME
-    H5T_vlen_reclaim
- PURPOSE
-    Default method to reclaim any VL data for a buffer element
- USAGE
-    herr_t H5T_vlen_reclaim(elem,type_id,ndim,point,op_data)
-        void *elem;  IN/OUT: Pointer to the dataset element
-        hid_t type_id;   IN: Datatype of dataset element
-        unsigned ndim;    IN: Number of dimensions in dataspace
-        hsize_t *point; IN: Coordinate location of element in dataspace
-        void *op_data    IN: Operator data
-
- RETURNS
-    SUCCEED/FAIL
- DESCRIPTION
-    Frees any dynamic memory used by VL datatypes in the current dataset
-    element.  Recursively descends compound datatypes to free all VL datatype
-    information allocated by any field.
- GLOBAL VARIABLES
- COMMENTS, BUGS, ASSUMPTIONS
- EXAMPLES
- REVISION LOG
---------------------------------------------------------------------------*/
-herr_t
-H5T_vlen_reclaim(void *elem, hid_t type_id, unsigned H5_ATTR_UNUSED ndim,
-    const hsize_t H5_ATTR_UNUSED *point, void *op_data)
-{
-    H5T_vlen_alloc_info_t *vl_alloc_info = (H5T_vlen_alloc_info_t *)op_data; /* VL allocation info from iterator */
-    H5T_t	*dt;
-    herr_t ret_value = SUCCEED;     /* Return value */
-
-    FUNC_ENTER_NOAPI(FAIL)
-
-    /* Sanity check */
-    HDassert(elem);
-    HDassert(vl_alloc_info);
-    HDassert(H5I_DATATYPE == H5I_get_type(type_id));
-
-    /* Check args */
-    if(NULL == (dt = (H5T_t *)H5I_object_verify(type_id, H5I_DATATYPE)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a datatype")
-
-    /* Pull the free function and free info pointer out of the op_data and call the recurse datatype free function */
-    if(H5T__vlen_reclaim_recurse(elem, dt, vl_alloc_info->free_func, vl_alloc_info->free_info) < 0)
-        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTFREE, FAIL, "can't reclaim vlen elements")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5T_vlen_reclaim() */
 
 
@@ -1295,10 +1237,9 @@ H5T_vlen_reclaim_elmt(void *elem, H5T_t *dt)
         HGOTO_ERROR(H5E_DATATYPE, H5E_CANTGET, FAIL, "unable to retrieve VL allocation info")
 
     /* Recurse on buffer to free dynamic fields */
-    if(H5T__vlen_reclaim_recurse(elem, dt, vl_alloc_info.free_func, vl_alloc_info.free_info) < 0)
+    if(H5T_vlen_reclaim(elem, dt, &vl_alloc_info) < 0)
         HGOTO_ERROR(H5E_DATATYPE, H5E_CANTFREE, FAIL, "can't reclaim vlen elements")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* H5T_vlen_reclaim_elmt() */
-
diff --git a/src/H5VLnative_file.c b/src/H5VLnative_file.c
index b67c0cf..63574c6 100644
--- a/src/H5VLnative_file.c
+++ b/src/H5VLnative_file.c
@@ -409,7 +409,6 @@ H5VL__native_file_specific(void *obj, H5VL_file_specific_t specific_type,
                 break;
             }
 
-
         default:
             HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "invalid specific operation")
     } /* end switch */
diff --git a/src/H5detect.c b/src/H5detect.c
index 32b7d34..d01ee9f 100644
--- a/src/H5detect.c
+++ b/src/H5detect.c
@@ -107,8 +107,8 @@ typedef struct detected_t {
     unsigned int comp_align;            /* alignment for structure          */
 } detected_t;
 
-/* This structure holds structure alignment for pointers, hvl_t, hobj_ref_t,
- * hdset_reg_ref_t */
+/* This structure holds structure alignment for pointers, vlen and reference
+ * types. */
 typedef struct malign_t {
     const char          *name;
     unsigned int         comp_align;    /* alignment for structure          */
@@ -383,9 +383,8 @@ precision (detected_t *d)
 /*-------------------------------------------------------------------------
  * Function:    DETECT_M
  *
- * Purpose:     This macro takes only miscellaneous structures or pointer
- *              (pointer, hvl_t, hobj_ref_t, hdset_reg_ref_t).  It
- *              constructs the names and decides the alignment in structure.
+ * Purpose:     This macro takes only miscellaneous structures or pointer.
+ *              It constructs the names and decides the alignment in structure.
  *
  * Return:      void
  *-------------------------------------------------------------------------
@@ -761,8 +760,8 @@ H5T__init_native(void)\n\
     H5T_native_order_g = H5T_ORDER_%s;\n", "BE");
     }
 
-    /* Structure alignment for pointers, hvl_t, hobj_ref_t, hdset_reg_ref_t */
-    fprintf(rawoutstream, "\n    /* Structure alignment for pointers, hvl_t, hobj_ref_t, hdset_reg_ref_t */\n");
+    /* Structure alignment for pointers, vlen and reference types */
+    fprintf(rawoutstream, "\n    /* Structure alignment for pointers, vlen and reference types */\n");
     for(j=0; j<na; j++)
         fprintf(rawoutstream, "    H5T_%s_COMP_ALIGN_g = %lu;\n", misc_align[j].name, (unsigned long)(misc_align[j].comp_align));
 
@@ -1544,11 +1543,12 @@ detect_C99_floats(void)
 static void HDF_NO_UBSAN
 detect_alignments(void)
 {
-    /* Detect structure alignment for pointers, hvl_t, hobj_ref_t, hdset_reg_ref_t */
+    /* Detect structure alignment for pointers, vlen and reference types */
     DETECT_M(void *,              POINTER,      m_g[na_g]); na_g++;
     DETECT_M(hvl_t,               HVL,          m_g[na_g]); na_g++;
     DETECT_M(hobj_ref_t,          HOBJREF,      m_g[na_g]); na_g++;
     DETECT_M(hdset_reg_ref_t,     HDSETREGREF,  m_g[na_g]); na_g++;
+    DETECT_M(H5R_ref_t,           REF,          m_g[na_g]); na_g++;
 }
 
 
diff --git a/src/H5trace.c b/src/H5trace.c
index 2eb7468..79dfbc8 100644
--- a/src/H5trace.c
+++ b/src/H5trace.c
@@ -34,6 +34,7 @@
 #include "H5Dprivate.h"     /* Datasets                                 */
 #include "H5Eprivate.h"     /* Error handling                           */
 #include "H5FDprivate.h"    /* File drivers                             */
+#include "H5Rprivate.h"     /* References                               */
 #include "H5Ipkg.h"         /* IDs                                      */
 #include "H5MMprivate.h"    /* Memory management                        */
 #include "H5VLprivate.h"    /* Virtual Object Layer                     */
@@ -1856,22 +1857,51 @@ H5_trace(const double *returning, const char *func, const char *type, ...)
                 } /* end else */
                 break;
 
-            case 'r':
-                if(ptr) {
-                    if(vp)
-                        HDfprintf(out, "0x%lx", (unsigned long)vp);
-                    else
-                        HDfprintf(out, "NULL");
-                } /* end if */
-                else {
-                    hobj_ref_t ref = HDva_arg(ap, hobj_ref_t);
-
-                    HDfprintf(out, "Reference Object=%a", ref);
-                } /* end else */
-                break;
-
             case 'R':
                 switch(type[1]) {
+
+                    case 'o':
+                        if(ptr) {
+                            if(vp)
+                                HDfprintf(out, "0x%lx", (unsigned long)vp);
+                            else
+                                HDfprintf(out, "NULL");
+                        } /* end if */
+                        else {
+                            hobj_ref_t ref = HDva_arg(ap, hobj_ref_t);
+
+                            HDfprintf(out, "Reference Object=%a", ref);
+                        } /* end else */
+                        break;
+
+                    case 'd':
+                        if(ptr) {
+                            if(vp)
+                                HDfprintf(out, "0x%lx", (unsigned long)vp);
+                            else
+                                HDfprintf(out, "NULL");
+                        } /* end if */
+                        else {
+                            /* Note! region references are array types */
+                            HDfprintf(out, "Reference Region");
+                            goto error;
+                        } /* end else */
+                        break;
+
+                    case 'r':
+                        if(ptr) {
+                            if(vp)
+                                HDfprintf(out, "0x%lx", (unsigned long)vp);
+                            else
+                                HDfprintf(out, "NULL");
+                        } /* end if */
+                        else {
+                            /* Note! reference types are opaque types */
+                            HDfprintf(out, "Reference Opaque");
+                            goto error;
+                        } /* end else */
+                        break;
+
                     case 't':
                         if(ptr) {
                             if(vp)
@@ -1887,12 +1917,24 @@ H5_trace(const double *returning, const char *func, const char *type, ...)
                                     HDfprintf(out, "H5R_BADTYPE");
                                     break;
 
-                                case H5R_OBJECT:
-                                    HDfprintf(out, "H5R_OBJECT");
+                                case H5R_OBJECT1:
+                                    HDfprintf(out, "H5R_OBJECT1");
+                                    break;
+
+                                case H5R_DATASET_REGION1:
+                                    HDfprintf(out, "H5R_DATASET_REGION1");
+                                    break;
+
+                                case H5R_OBJECT2:
+                                    HDfprintf(out, "H5R_OBJECT2");
+                                    break;
+
+                                case H5R_DATASET_REGION2:
+                                    HDfprintf(out, "H5R_DATASET_REGION2");
                                     break;
 
-                                case H5R_DATASET_REGION:
-                                    HDfprintf(out, "H5R_DATASET_REGION");
+                                case H5R_ATTR:
+                                    HDfprintf(out, "H5R_ATTR");
                                     break;
 
                                 case H5R_MAXTYPE:
diff --git a/src/Makefile.am b/src/Makefile.am
index 24dfe74..fa412c9 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -83,7 +83,7 @@ libhdf5_la_SOURCES= H5.c H5checksum.c H5dbg.c H5system.c H5timer.c H5trace.c \
         H5O.c H5Odeprec.c H5Oainfo.c H5Oalloc.c H5Oattr.c \
         H5Oattribute.c H5Obogus.c H5Obtreek.c H5Ocache.c H5Ocache_image.c \
         H5Ochunk.c \
-        H5Ocont.c H5Ocopy.c H5Odbg.c H5Odrvinfo.c H5Odtype.c H5Oefl.c \
+        H5Ocont.c H5Ocopy.c H5Ocopy_ref.c H5Odbg.c H5Odrvinfo.c H5Odtype.c H5Oefl.c \
         H5Ofill.c H5Oflush.c H5Ofsinfo.c H5Oginfo.c \
         H5Oint.c H5Olayout.c \
         H5Olinfo.c H5Olink.c H5Omessage.c H5Omtime.c \
@@ -114,6 +114,7 @@ libhdf5_la_SOURCES= H5.c H5checksum.c H5dbg.c H5system.c H5timer.c H5trace.c \
         H5Tfloat.c H5Tinit.c H5Tnative.c H5Toffset.c H5Toh.c \
         H5Topaque.c \
         H5Torder.c \
+        H5Tref.c \
         H5Tpad.c H5Tprecis.c H5Tstrpad.c H5Tvisit.c H5Tvlen.c H5TS.c \
         H5VL.c H5VLcallback.c H5VLint.c H5VLnative.c \
         H5VLnative_attr.c H5VLnative_blob.c H5VLnative_dataset.c \
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 8184d7f..c7a945e 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -194,6 +194,7 @@ set (testhdf5_SOURCES
     ${HDF5_TEST_SOURCE_DIR}/tmeta.c
     ${HDF5_TEST_SOURCE_DIR}/tmisc.c
     ${HDF5_TEST_SOURCE_DIR}/trefer.c
+    ${HDF5_TEST_SOURCE_DIR}/trefer_deprec.c
     ${HDF5_TEST_SOURCE_DIR}/trefstr.c
     ${HDF5_TEST_SOURCE_DIR}/tselect.c
     ${HDF5_TEST_SOURCE_DIR}/tskiplist.c
@@ -250,6 +251,7 @@ set (H5_TESTS
     external
     external_env
     efc
+    objcopy_ref
     objcopy
     links
     unlink
diff --git a/test/Makefile.am b/test/Makefile.am
index a19079d..57080aa 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -59,7 +59,7 @@ TEST_PROG= testhdf5 \
            stab gheap evict_on_close farray earray btree2 fheap \
            pool accum hyperslab istore bittests dt_arith page_buffer \
            dtypes dsets chunk_info cmpd_dset filter_fail extend direct_chunk \
-           external efc objcopy links unlink twriteorder big mtime fillval mount \
+           external efc objcopy objcopy_ref links unlink twriteorder big mtime fillval mount \
            flush1 flush2 app_ref enum set_extent ttsafe enc_dec_plist \
            enc_dec_plist_cross_platform getname vfd ros3 s3comms hdfs ntypes \
            dangle dtransform reserved cross_read freespace mf vds file_image \
@@ -190,7 +190,7 @@ CHECK_CLEANFILES+=accum.h5 cmpd_dset.h5 compact_dataset.h5 dataset.h5 dset_offse
     stdio.h5 sec2.h5 dtypes[0-9].h5 dtypes1[0].h5 dt_arith[1-2].h5 tattr.h5 \
     tselect.h5 mtime.h5 unlink.h5 unicode.h5 coord.h5 \
     fillval_[0-9].h5 fillval.raw mount_[0-9].h5 testmeta.h5 ttime.h5 \
-    trefer[1-3].h5 tvltypes.h5 tvlstr.h5 tvlstr2.h5 twriteorder.dat \
+    trefer[1-3].h5 trefer_*.h5 tvltypes.h5 tvlstr.h5 tvlstr2.h5 twriteorder.dat \
     flush.h5 flush-swmr.h5 noflush.h5 noflush-swmr.h5 flush_extend.h5 \
     flush_extend-swmr.h5 noflush_extend.h5 noflush_extend-swmr.h5 \
     enum1.h5 titerate.h5 ttsafe.h5 tarray1.h5 tgenprop.h5            \
@@ -218,7 +218,7 @@ CHECK_CLEANFILES+=accum.h5 cmpd_dset.h5 compact_dataset.h5 dataset.h5 dset_offse
 # Sources for testhdf5 executable
 testhdf5_SOURCES=testhdf5.c tarray.c tattr.c tchecksum.c tconfig.c tfile.c \
     tgenprop.c th5o.c th5s.c tcoords.c theap.c tid.c titerate.c tmeta.c tmisc.c \
-    trefer.c trefstr.c tselect.c tskiplist.c tsohm.c ttime.c ttst.c tunicode.c \
+    trefer.c trefer_deprec.c trefstr.c tselect.c tskiplist.c tsohm.c ttime.c ttst.c tunicode.c \
     tvlstr.c tvltypes.c
 
 # Sources for Use Cases
diff --git a/test/objcopy_ref.c b/test/objcopy_ref.c
new file mode 100644
index 0000000..721a7c6
--- /dev/null
+++ b/test/objcopy_ref.c
@@ -0,0 +1,1739 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the COPYING file, which can be found at the root of the source code       *
+ * distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.  *
+ * If you do not have access to either file, you may request a copy from     *
+ * help@hdfgroup.org.                                                        *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*
+ * Programmer:     Peter X. Cao
+ *                 May 01, 2005
+ *
+ * Purpose:    Test H5Ocopy() for references.
+ */
+
+#include "testhdf5.h"
+
+#define H5F_FRIEND      /*suppress error about including H5Fpkg */
+#define H5F_TESTING
+#include "H5Fpkg.h"     /* File access                          */
+
+const char *FILENAME[] = {
+    "objcopy_ref_src",
+    "objcopy_ref_dst",
+    "objcopy_ref_ext",
+    "objcopy_ref_src2",
+    "verbound_ref_src",
+    "verbound_ref_dst",
+    NULL
+};
+
+/* Configuration, really a series of bit flags.  Maximum value is all three
+ * bit flags enabled.
+ */
+#define CONFIG_SHARE_SRC 1
+#define CONFIG_SHARE_DST 2
+#define CONFIG_SRC_NEW_FORMAT 4
+#define CONFIG_DST_NEW_FORMAT 8
+#define CONFIG_DENSE 16
+#define MAX_CONFIGURATION 31
+
+#define NAME_DATATYPE_SIMPLE     "H5T_NATIVE_INT"
+#define NAME_DATATYPE_SIMPLE2     "H5T_NATIVE_INT-2"
+#define NAME_DATATYPE_VL     "vlen of int"
+#define NAME_DATATYPE_VL_VL     "vlen of vlen of int"
+#define NAME_DATASET_SIMPLE     "dataset_simple"
+#define NAME_DATASET_SIMPLE2    "dataset_simple_copy"
+#define NAME_DATASET_SIMPLE3    "dataset_simple_another_copy"
+#define NAME_DATASET_COMPOUND     "dataset_compound"
+#define NAME_DATASET_CHUNKED     "dataset_chunked"
+#define NAME_DATASET_CHUNKED_SINGLE     "dataset_chunked_single"
+#define NAME_DATASET_CHUNKED2     "dataset_chunked2"
+#define NAME_DATASET_CHUNKED2_SINGLE     "dataset_chunked2_single"
+#define NAME_DATASET_CHUNKED3     "dataset_chunked3"
+#define NAME_DATASET_CHUNKED3_SINGLE     "dataset_chunked3_single"
+#define NAME_DATASET_CHUNKED4     "dataset_chunked4"
+#define NAME_DATASET_CHUNKED4_SINGLE     "dataset_chunked4_single"
+#define NAME_DATASET_COMPACT     "dataset_compact"
+#define NAME_DATASET_EXTERNAL     "dataset_ext"
+#define NAME_DATASET_NAMED_DTYPE     "dataset_named_dtype"
+#define NAME_DATASET_NAMED_DTYPE2     "dataset_named_dtype2"
+#define NAME_DATASET_MULTI_OHDR     "dataset_multi_ohdr"
+#define NAME_DATASET_MULTI_OHDR2     "dataset_multi_ohdr2"
+#define NAME_DATASET_VL     "dataset_vl"
+#define NAME_DATASET_VL2     "dataset_vl2"
+#define NAME_DATASET_VL_VL     "dataset_vl_vl"
+#define NAME_DATASET_VL_VL2     "dataset_vl_vl2"
+#define NAME_DATASET_CMPD_VL     "dataset_cmpd_vl"
+#define NAME_DATASET_SUB_SUB     "/g0/g00/g000/dataset_simple"
+#define NAME_GROUP_UNCOPIED     "/uncopied"
+#define NAME_GROUP_EMPTY     "/empty"
+#define NAME_GROUP_TOP         "/g0"
+#define NAME_GROUP_TOP2         "/g1"
+#define NAME_GROUP_TOP3         "/g2"
+#define NAME_GROUP_TOP4         "/g3"
+#define NAME_GROUP_SUB         "/g0/g00"
+#define NAME_GROUP_SUB_2    "/g0/g01"
+#define NAME_GROUP_SUB_SUB     "/g0/g00/g000"
+#define NAME_GROUP_SUB_SUB2     "g000"
+#define NAME_GROUP_DATASET     "/g0/dataset_simple"
+#define NAME_GROUP_LINK        "/g_links"
+#define NAME_GROUP_LINK2    "/g_links2"
+#define NAME_GROUP_LOOP        "g_loop"
+#define NAME_GROUP_LOOP2    "g_loop2"
+#define NAME_GROUP_LOOP3    "g_loop3"
+#define NAME_GROUP_REF            "ref_grp"
+#define NAME_LINK_DATASET    "/g_links/dataset_simple"
+#define NAME_LINK_HARD        "/g_links/hard_link_to_dataset_simple"
+#define NAME_LINK_SOFT        "/g_links/soft_link_to_dataset_simple"
+#define NAME_LINK_SOFT2        "/g_links2/soft_link_to_dataset_simple"
+#define NAME_LINK_EXTERN    "/g_links/external_link_to_dataset_simple"
+#define NAME_LINK_EXTERN2       "/g_links2/external_link_to_dataset_simple"
+#define NAME_LINK_SOFT_DANGLE    "/g_links/soft_link_to_nowhere"
+#define NAME_LINK_SOFT_DANGLE2    "/g_links2/soft_link_to_nowhere"
+#define NAME_LINK_EXTERN_DANGLE "/g_links/external_link_to_nowhere"
+#define NAME_LINK_EXTERN_DANGLE2        "/g_links2/external_link_to_nowhere"
+#define NAME_OLD_FORMAT        "/dset1"
+
+#define NAME_BUF_SIZE   1024
+#define ATTR_NAME_LEN 80
+#define DIM_SIZE_1 12
+#define DIM_SIZE_2  6
+#define MAX_DIM_SIZE_1    100
+#define MAX_DIM_SIZE_2    80
+#define CHUNK_SIZE_1 5          /* Not an even fraction of dimension sizes, so we test copying partial chunks */
+#define CHUNK_SIZE_2 5
+#define NUM_SUB_GROUPS  20
+#define NUM_WIDE_LOOP_GROUPS  10
+#define NUM_DATASETS  10
+
+unsigned num_attributes_g;         /* Number of attributes created */
+
+/* Table containing object id and object name */
+/* (Used for detecting duplicate objects when comparing groups */
+static struct {
+    size_t  nalloc;             /* number of slots allocated */
+    size_t  nobjs;              /* number of objects */
+    haddr_t *obj;               /* Addresses of objects seen */
+} idtab_g;
+
+/* Local function prototypes */
+static int
+compare_data(hid_t parent1, hid_t parent2, hid_t pid, hid_t tid, size_t nelmts,
+            const void *buf1, const void *buf2, hid_t obj_owner);
+static int
+compare_datasets(hid_t did, hid_t did2, hid_t pid, const void *wbuf);
+static int
+compare_groups(hid_t gid, hid_t gid2, hid_t pid, int depth, unsigned copy_flags);
+
+/*-------------------------------------------------------------------------
+ * Function: addr_insert
+ *
+ * Purpose: Add an address to the table.
+ *
+ * Return: void
+ *
+ * Programmer: Quincey Koziol
+ *              Saturday, November  5, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static void
+addr_insert(H5O_info_t *oi)
+{
+    size_t  n;
+
+    /* Don't add it if the link count is 1 because such an object can only
+     * be encountered once. */
+    if(oi->rc < 2)
+        return;
+
+    /* Extend the table */
+    if(idtab_g.nobjs >= idtab_g.nalloc) {
+        idtab_g.nalloc = MAX(256, 2*idtab_g.nalloc);
+        idtab_g.obj = (haddr_t *)HDrealloc(idtab_g.obj, idtab_g.nalloc * sizeof(idtab_g.obj[0]));
+    } /* end if */
+
+    /* Insert the entry */
+    n = idtab_g.nobjs++;
+    idtab_g.obj[n] = oi->addr;
+} /* end addr_insert() */
+
+
+/*-------------------------------------------------------------------------
+ * Function: addr_lookup
+ *
+ * Purpose: Check if address has already been encountered
+ *
+ * Return: Success: TRUE/FALSE
+ *
+ * Failure: (can't fail)
+ *
+ * Programmer: Quincey Koziol
+ *              Saturday, November  5, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static H5_ATTR_PURE hbool_t
+addr_lookup(H5O_info_t *oi)
+{
+    size_t  n;
+
+    if(oi->rc < 2) return FALSE; /*only one link possible*/
+
+    for(n = 0; n < idtab_g.nobjs; n++)
+        if(H5F_addr_eq(idtab_g.obj[n], oi->addr))
+            return TRUE;
+
+    return FALSE;
+} /* end addr_lookup() */
+
+
+/*-------------------------------------------------------------------------
+ * Function: addr_reset
+ *
+ * Purpose: Reset the address tracking data structures
+ *
+ * Return: void
+ *
+ * Programmer: Quincey Koziol
+ *              Saturday, November  5, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static void
+addr_reset(void)
+{
+    if(idtab_g.obj)
+        HDfree(idtab_g.obj);
+    idtab_g.obj = NULL;
+    idtab_g.nalloc = idtab_g.nobjs = 0;
+} /* end addr_reset() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    attach_ref_attr
+ *
+ * Purpose:     Create an attribute with object references
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+attach_ref_attr(hid_t file_id, hid_t loc_id)
+{
+    char dsetname1[] = "dataset1_pointed_by_ref_attr";
+    char dsetname2[] = "dataset2_pointed_by_ref_attr";
+    hid_t did1 = (-1), did2 = (-1), aid = (-1), sid = (-1), sid_ref = (-1);
+    hsize_t dims[2] =  {2,9};
+    hsize_t dims_ref[1] = {2};
+    H5R_ref_t ref[2];
+    int data1[2][9] = {{1,1,1,1,1,1,1,1,1},{1,1,1,1,1,1,1,1,18}};
+    int data2[2][9] = {{2,2,2,2,2,2,2,2,2},{2,2,2,2,2,2,2,2,18}};
+
+    /* creates two simple datasets */
+    if((sid = H5Screate_simple(2, dims, NULL)) < 0) TEST_ERROR
+    if((sid_ref = H5Screate_simple(1, dims_ref, NULL)) < 0) TEST_ERROR
+    if((did1 = H5Dcreate2(file_id, dsetname1, H5T_NATIVE_INT, sid,  H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Dwrite(did1, H5T_NATIVE_INT, H5S_ALL , H5S_ALL, H5P_DEFAULT,data1) < 0) TEST_ERROR
+    if((did2 = H5Dcreate2(file_id, dsetname2, H5T_NATIVE_INT, sid,  H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Dwrite(did2, H5T_NATIVE_INT, H5S_ALL , H5S_ALL, H5P_DEFAULT,data2) < 0) TEST_ERROR
+
+    /* create an attribute with two object references */
+    if(H5Rcreate_object(file_id, dsetname1, &ref[0]) < 0) TEST_ERROR
+    if(H5Rcreate_object(file_id, dsetname2, &ref[1]) < 0) TEST_ERROR
+    if((aid = H5Acreate2(loc_id, "obj_ref_attr", H5T_STD_REF, sid_ref, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Awrite(aid, H5T_STD_REF, ref) < 0) TEST_ERROR
+
+    if(H5Sclose(sid) < 0) TEST_ERROR
+    if(H5Sclose(sid_ref) < 0) TEST_ERROR
+    if(H5Dclose(did1) < 0) TEST_ERROR
+    if(H5Dclose(did2) < 0) TEST_ERROR
+    if(H5Aclose(aid) < 0) TEST_ERROR
+    if(H5Rdestroy(&ref[0]) < 0) TEST_ERROR
+    if(H5Rdestroy(&ref[1]) < 0) TEST_ERROR
+
+    return 0;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Sclose(sid);
+        H5Sclose(sid_ref);
+        H5Dclose(did1);
+        H5Dclose(did2);
+        H5Aclose(aid);
+        H5Rdestroy(&ref[0]);
+        H5Rdestroy(&ref[1]);
+    } H5E_END_TRY;
+
+    return(-1);
+}
+
+/*-------------------------------------------------------------------------
+ * Function:    attach_reg_ref_attr
+ *
+ * Purpose:     Create an attribute with object references
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Peter Cao
+ *              Monday, March 5, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+attach_reg_ref_attr(hid_t file_id, hid_t loc_id)
+{
+    const char dsetnamev[] = "dataset_pointed_by_reg_ref_attr";
+    hid_t aid = (-1);
+    hid_t space_id = (-1);       /* dataspace identifiers */
+    hid_t spacer_id = (-1);       /* dataspace identifiers */
+    hid_t dsetv_id = (-1);       /*dataset identifiers*/
+    hsize_t dims[2] =  {2,9};
+    hsize_t dimsr[1] =  {2};
+    int rank = 2;
+    int rankr =1;
+    H5R_ref_t ref[2];
+    int data[2][9] = {{1,1,2,3,3,4,5,5,999},{1,2,2,3,4,4,5,6,999}};
+    hsize_t start[2] = {0, 3};
+    hsize_t count[2] = {2, 3};
+    hsize_t coord[3][2] = {{0, 0}, {1, 6}, {0, 8}};
+    size_t num_points = 3;
+
+    /* create a 2D dataset */
+    if((space_id = H5Screate_simple(rank, dims, NULL)) < 0) TEST_ERROR
+    if((spacer_id = H5Screate_simple(rankr, dimsr, NULL)) < 0) TEST_ERROR
+    if((dsetv_id = H5Dcreate2(file_id, dsetnamev, H5T_NATIVE_INT, space_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Dwrite(dsetv_id, H5T_NATIVE_INT, H5S_ALL , H5S_ALL, H5P_DEFAULT,data) < 0) TEST_ERROR
+
+    /* create reg_ref of block selection */
+    if(H5Sselect_hyperslab(space_id,H5S_SELECT_SET,start,NULL,count,NULL) < 0) TEST_ERROR
+    if(H5Rcreate_region(file_id, dsetnamev, space_id, &ref[0]) < 0) TEST_ERROR
+
+    /* create reg_ref of point selection */
+    if(H5Sselect_none(space_id) < 0) TEST_ERROR
+    if(H5Sselect_elements(space_id, H5S_SELECT_SET, num_points, (const hsize_t *)coord) < 0) TEST_ERROR
+    if(H5Rcreate_region(file_id, dsetnamev, space_id, &ref[1]) < 0) TEST_ERROR
+
+    /* create reg_ref attribute */
+    if((aid = H5Acreate2(loc_id, "reg_ref_attr", H5T_STD_REF, spacer_id, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Awrite(aid, H5T_STD_REF, ref) < 0) TEST_ERROR
+
+    /* attach the reg_ref attribute to the dataset itself */
+    if(H5Aclose(aid) < 0) TEST_ERROR
+    if((aid = H5Acreate2(dsetv_id, "reg_ref_attr", H5T_STD_REF, spacer_id, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Awrite(aid, H5T_STD_REF, ref) < 0) TEST_ERROR
+
+    if(H5Sclose(spacer_id) < 0) TEST_ERROR
+    if(H5Sclose(space_id) < 0) TEST_ERROR
+    if(H5Dclose(dsetv_id) < 0) TEST_ERROR
+    if(H5Aclose(aid) < 0) TEST_ERROR
+    if(H5Rdestroy(&ref[0]) < 0) TEST_ERROR
+    if(H5Rdestroy(&ref[1]) < 0) TEST_ERROR
+
+
+    return 0;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Sclose(spacer_id);
+        H5Sclose(space_id);
+        H5Dclose(dsetv_id);
+        H5Aclose(aid);
+        H5Rdestroy(&ref[0]);
+        H5Rdestroy(&ref[1]);
+    } H5E_END_TRY;
+
+    return(-1);
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function:    create_reg_ref_dataset
+ *
+ * Purpose:     Create a dataset with region references
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Peter Cao
+ *              Friday, August 4, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+create_reg_ref_dataset(hid_t file_id, hid_t loc_id)
+{
+    const char dsetnamev[] = "dataset_pointed_by_ref_dset";
+    const char dsetnamer[] = "dataset_with_reg_ref";
+    const char dsetnamer1[] = "compact_dataset_with_reg_ref";
+    const char dsetnamer2[] = "compressed_dataset_with_reg_ref";
+    hid_t space_id = (-1);       /* dataspace identifiers */
+    hid_t spacer_id = (-1);
+    hid_t dsetv_id = (-1);       /*dataset identifiers*/
+    hid_t dsetr_id = (-1);
+    hsize_t dims[2] =  {2,9};
+    hsize_t dimsr[1] =  {2};
+    int rank = 2;
+    int rankr =1;
+    hsize_t chunk_size=1;
+    H5R_ref_t ref[2];
+    int data[2][9] = {{1,1,2,3,3,4,5,5,6},{1,2,2,3,4,4,5,6,6}};
+    hsize_t start[2];
+    hsize_t count[2];
+    hsize_t coord[3][2] = {{0, 0}, {1, 6}, {0, 8}};
+    size_t num_points = 3;
+    hid_t pid = (-1);
+
+    if((space_id = H5Screate_simple(rank, dims, NULL)) < 0) TEST_ERROR
+    if((spacer_id = H5Screate_simple(rankr, dimsr, NULL)) < 0) TEST_ERROR
+    if((dsetv_id = H5Dcreate2(file_id, dsetnamev, H5T_NATIVE_INT, space_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Dwrite(dsetv_id, H5T_NATIVE_INT, H5S_ALL , H5S_ALL, H5P_DEFAULT,data) < 0) TEST_ERROR
+    if((dsetr_id = H5Dcreate2(loc_id, dsetnamer, H5T_STD_REF, spacer_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+
+    start[0] = 0;
+    start[1] = 3;
+    count[0] = 2;
+    count[1] = 3;
+    if(H5Sselect_hyperslab(space_id,H5S_SELECT_SET,start,NULL,count,NULL) < 0) TEST_ERROR
+    if(H5Rcreate_region(file_id, dsetnamev, space_id, &ref[0]) < 0) TEST_ERROR
+    if(H5Sselect_none(space_id) < 0) TEST_ERROR
+    if(H5Sselect_elements(space_id, H5S_SELECT_SET, num_points, (const hsize_t *)coord) < 0) TEST_ERROR
+    if(H5Rcreate_region(file_id, dsetnamev, space_id, &ref[1]) < 0) TEST_ERROR
+    if(H5Dwrite(dsetr_id, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT,ref) < 0) TEST_ERROR
+    if(H5Dclose(dsetr_id) < 0) TEST_ERROR
+
+    /* create and set compact plist */
+    if((pid = H5Pcreate(H5P_DATASET_CREATE)) < 0) TEST_ERROR
+    if(H5Pset_layout(pid, H5D_COMPACT) < 0) TEST_ERROR
+
+    if((dsetr_id = H5Dcreate2(loc_id, dsetnamer1, H5T_STD_REF, spacer_id, H5P_DEFAULT, pid, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Pclose(pid) < 0) TEST_ERROR
+    if(H5Dwrite(dsetr_id, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, ref) < 0) TEST_ERROR
+    if(H5Dclose(dsetr_id) < 0) TEST_ERROR
+
+    /* create and set comp & chunk plist */
+    if((pid = H5Pcreate(H5P_DATASET_CREATE)) < 0) TEST_ERROR
+    if(H5Pset_chunk(pid, 1, &chunk_size) < 0) TEST_ERROR
+    if(H5Pset_deflate(pid, 9) < 0) TEST_ERROR
+
+    if((dsetr_id = H5Dcreate2(loc_id, dsetnamer2, H5T_STD_REF, spacer_id, H5P_DEFAULT, pid, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Pclose(pid) < 0) TEST_ERROR
+    if(H5Dwrite(dsetr_id, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT,ref) < 0) TEST_ERROR
+    if(H5Dclose(dsetr_id) < 0) TEST_ERROR
+
+    if(H5Sclose(space_id) < 0) TEST_ERROR
+    if(H5Sclose(spacer_id) < 0) TEST_ERROR
+    if(H5Dclose(dsetv_id) < 0) TEST_ERROR
+    if(H5Rdestroy(&ref[0]) < 0) TEST_ERROR
+    if(H5Rdestroy(&ref[1]) < 0) TEST_ERROR
+
+    return 0;
+
+
+error:
+    H5E_BEGIN_TRY {
+        H5Sclose(space_id);
+        H5Sclose(spacer_id);
+        H5Dclose(dsetr_id);
+        H5Dclose(dsetv_id);
+        H5Pclose(pid);
+        H5Rdestroy(&ref[0]);
+        H5Rdestroy(&ref[1]);
+    } H5E_END_TRY;
+
+    return(-1);
+}
+
+/*-------------------------------------------------------------------------
+ * Function:    test_copy_attach_attributes
+ *
+ * Purpose:     Attach NUM_ATTRIBUTES attributes to the object to be copied
+ *
+ * Return:    Non-negative on success/Negative on failure
+ *
+ * Programmer:  Peter Cao
+ *              Friday, September 30, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+test_copy_attach_attributes(hid_t loc_id, hid_t type_id)
+{
+    hid_t aid = -1, sid = -1;
+    char attr_name[ATTR_NAME_LEN];
+    int  attr_data[2];
+    hsize_t dim1 = 2;
+    hid_t acpl = -1;
+    unsigned  u;
+    int ret_value = -1;
+
+    if((sid = H5Screate_simple(1, &dim1, NULL)) < 0 )
+        goto done;
+
+    /* Create attribute creation plist */
+    if((acpl = H5Pcreate(H5P_ATTRIBUTE_CREATE)) < 0)
+        goto done;
+
+    for(u = 0; u < num_attributes_g; u++) {
+        HDsprintf(attr_name, "%u attr", u);
+
+        /* Set attribute data */
+        attr_data[0] = (int)(100 * u);
+        attr_data[1] = (int)(200 * u);
+
+        /* Set attribute character set (alternate) */
+        if(u % 2) {
+            if(H5Pset_char_encoding(acpl, H5T_CSET_ASCII) < 0)
+                goto done;
+        } /* end if */
+        else
+            if(H5Pset_char_encoding(acpl, H5T_CSET_UTF8) < 0)
+                goto done;
+
+        if((aid = H5Acreate2(loc_id, attr_name, type_id, sid, acpl, H5P_DEFAULT)) < 0)
+            goto done;
+
+        if(H5Awrite(aid, H5T_NATIVE_INT, attr_data) < 0)
+            goto done;
+
+        if(aid > 0)
+            H5Aclose(aid);
+
+         aid = -1;
+    }
+
+    ret_value = 0;
+
+done:
+    if(sid > 0)
+        H5Sclose(sid);
+    if(aid > 0)
+        H5Aclose(aid);
+    if(acpl > 0)
+        H5Pclose(acpl);
+
+    return ret_value;
+}
+
+/*-------------------------------------------------------------------------
+ * Function:    compare_attribute
+ *
+ * Purpose:     Compare two attributes to check that they are equal
+ *
+ * Return:      TRUE if attributes are equal/FALSE if they are different
+ *
+ * Programmer:  Peter Cao
+ *              Saturday, December 17, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+compare_attribute(hid_t aid, hid_t aid2, hid_t pid, const void *wbuf, hid_t obj_owner)
+{
+    hid_t sid = -1, sid2 = -1;                  /* Dataspace IDs */
+    hid_t tid = -1, tid2 = -1;                  /* Datatype IDs */
+    size_t elmt_size;                           /* Size of datatype */
+    htri_t is_committed;                        /* If the datatype is committed */
+    htri_t is_committed2;                       /* If the datatype is committed */
+    H5A_info_t ainfo;                           /* Attribute info */
+    H5A_info_t ainfo2;                          /* Attribute info */
+    hssize_t nelmts;                            /* # of elements in dataspace */
+    void *rbuf = NULL;                          /* Buffer for reading raw data */
+    void *rbuf2 = NULL;                         /* Buffer for reading raw data */
+
+    /* Check the character sets are equal */
+    if(H5Aget_info(aid, &ainfo) < 0) TEST_ERROR
+    if(H5Aget_info(aid2, &ainfo2) < 0) TEST_ERROR
+    if(ainfo.cset != ainfo2.cset) TEST_ERROR
+
+    /* Check the creation orders are equal (if appropriate) */
+    if(ainfo.corder_valid != ainfo2.corder_valid) TEST_ERROR
+    if(ainfo.corder_valid)
+        if(ainfo.corder != ainfo2.corder) TEST_ERROR
+
+    /* Check the datatypes are equal */
+
+    /* Open the datatype for the source attribute */
+    if((tid = H5Aget_type(aid)) < 0) TEST_ERROR
+
+    /* Open the datatype for the destination attribute */
+    if((tid2 = H5Aget_type(aid2)) < 0) TEST_ERROR
+
+    /* Check that both datatypes are committed/not committed */
+    if((is_committed = H5Tcommitted(tid)) < 0) TEST_ERROR
+    if((is_committed2 = H5Tcommitted(tid2)) < 0) TEST_ERROR
+    if(is_committed != is_committed2) TEST_ERROR
+
+    /* Compare the datatypes */
+    if(H5Tequal(tid, tid2) != TRUE) TEST_ERROR
+
+    /* Determine the size of datatype (for later) */
+    if((elmt_size = H5Tget_size(tid)) == 0) TEST_ERROR
+
+    /* Check the dataspaces are equal */
+
+    /* Open the dataspace for the source attribute */
+    if((sid = H5Aget_space(aid)) < 0) TEST_ERROR
+
+    /* Open the dataspace for the destination attribute */
+    if((sid2 = H5Aget_space(aid2)) < 0) TEST_ERROR
+
+    /* Compare the dataspaces */
+    if(H5Sextent_equal(sid, sid2) != TRUE) TEST_ERROR
+
+    /* Determine the number of elements in dataspace (for later) */
+    if((nelmts = H5Sget_simple_extent_npoints(sid2)) < 0) TEST_ERROR
+
+    /* Check the raw data is equal */
+
+    /* Allocate & initialize space for the raw data buffers */
+    if((rbuf = HDcalloc( elmt_size, (size_t)nelmts)) == NULL) TEST_ERROR
+    if((rbuf2 = HDcalloc( elmt_size, (size_t)nelmts)) == NULL) TEST_ERROR
+
+    /* Read data from the source attribute */
+    if(H5Aread(aid, tid, rbuf) < 0) TEST_ERROR
+
+    /* Read data from the destination attribute */
+    if(H5Aread(aid2, tid2, rbuf2) < 0) TEST_ERROR
+
+    /* Check raw data read in against data written out */
+    if(wbuf) {
+        if(!compare_data(aid, (hid_t)0, pid, tid, (size_t)nelmts, wbuf, rbuf, obj_owner)) TEST_ERROR
+        if(!compare_data(aid2, (hid_t)0, pid, tid2, (size_t)nelmts, wbuf, rbuf2, obj_owner)) TEST_ERROR
+    } /* end if */
+    /* Don't have written data, just compare data between the two attributes */
+    else
+        if(!compare_data(aid, aid2, pid, tid, (size_t)nelmts, rbuf, rbuf2, obj_owner)) TEST_ERROR
+
+    /* Reclaim vlen data, if necessary */
+    if(H5Tdetect_class(tid, H5T_VLEN) == TRUE || H5Tdetect_class(tid, H5T_REFERENCE) == TRUE)
+        if(H5Treclaim(tid, sid, H5P_DEFAULT, rbuf) < 0) TEST_ERROR
+    if(H5Tdetect_class(tid2, H5T_VLEN) == TRUE || H5Tdetect_class(tid2, H5T_REFERENCE) == TRUE)
+        if(H5Treclaim(tid2, sid2, H5P_DEFAULT, rbuf2) < 0) TEST_ERROR
+
+    /* Release raw data buffers */
+    HDfree(rbuf);
+    rbuf = NULL;
+    HDfree(rbuf2);
+    rbuf2 = NULL;
+
+    /* close the source dataspace */
+    if(H5Sclose(sid) < 0) TEST_ERROR
+
+    /* close the destination dataspace */
+    if(H5Sclose(sid2) < 0) TEST_ERROR
+
+    /* close the source datatype */
+    if(H5Tclose(tid) < 0) TEST_ERROR
+
+    /* close the destination datatype */
+    if(H5Tclose(tid2) < 0) TEST_ERROR
+
+    return TRUE;
+
+error:
+    if(rbuf)
+        HDfree(rbuf);
+    if(rbuf2)
+        HDfree(rbuf2);
+    H5E_BEGIN_TRY {
+        H5Sclose(sid2);
+        H5Sclose(sid);
+        H5Tclose(tid2);
+        H5Tclose(tid);
+    } H5E_END_TRY;
+    return FALSE;
+} /* end compare_attribute() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    compare_std_attributes
+ *
+ * Purpose:     Compare "standard" attributes on two objects to check that they are equal
+ *
+ * Return:    TRUE if objects have same attributes/FALSE if they are different
+ *
+ * Programmer:  Quincey Koziol
+ *              Monday, October 31, 2005
+ *
+ * Note:    This isn't very general, the attributes are assumed to be
+ *              those written in test_copy_attach_attributes().
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+compare_std_attributes(hid_t oid, hid_t oid2, hid_t pid)
+{
+    hid_t aid = -1, aid2 = -1;                  /* Attribute IDs */
+    H5O_info_t oinfo1, oinfo2;                  /* Object info */
+    unsigned cpy_flags;                         /* Object copy flags */
+
+    /* Retrieve the object copy flags from the property list, if it's non-DEFAULT */
+    if(pid != H5P_DEFAULT) {
+        if(H5Pget_copy_object(pid, &cpy_flags) < 0) TEST_ERROR
+    } /* end if */
+    else
+        cpy_flags = 0;
+
+    /* Check the number of attributes on source dataset */
+    if(H5Oget_info2(oid, &oinfo1, H5O_INFO_NUM_ATTRS) < 0) TEST_ERROR
+
+    /* Check the number of attributes on destination dataset */
+    if(H5Oget_info2(oid2, &oinfo2, H5O_INFO_NUM_ATTRS) < 0) TEST_ERROR
+
+    if(cpy_flags & H5O_COPY_WITHOUT_ATTR_FLAG) {
+        /* Check that the destination has no attributes */
+        if(oinfo2.num_attrs != 0) TEST_ERROR
+    } /* end if */
+    else {
+        char attr_name[ATTR_NAME_LEN];  /* Attribute name */
+        unsigned i;             /* Local index variable */
+
+        /* Compare the number of attributes */
+        if(oinfo1.num_attrs != oinfo2.num_attrs) TEST_ERROR
+
+        /* Check the attributes are equal */
+        for(i = 0; i < (unsigned)oinfo1.num_attrs; i++) {
+            if((aid = H5Aopen_by_idx(oid, ".", H5_INDEX_CRT_ORDER, H5_ITER_INC, (hsize_t)i, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+            if(H5Aget_name(aid, (size_t)ATTR_NAME_LEN, attr_name) < 0) TEST_ERROR
+
+            if((aid2 = H5Aopen(oid2, attr_name, H5P_DEFAULT)) < 0) TEST_ERROR
+
+            /* Check the attributes are equal */
+            if(!compare_attribute(aid, aid2, pid, NULL, oid)) TEST_ERROR
+
+            /* Close the attributes */
+            if(H5Aclose(aid) < 0) TEST_ERROR
+            if(H5Aclose(aid2) < 0) TEST_ERROR
+        } /* end for */
+    } /* end if */
+
+    /* Objects should be the same. :-) */
+    return TRUE;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Aclose(aid2);
+        H5Aclose(aid);
+    } H5E_END_TRY;
+    return FALSE;
+} /* end compare_std_attributes() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    compare_data
+ *
+ * Purpose:     Compare two buffers of data to check that they are equal
+ *
+ * Return:    TRUE if buffer are equal/FALSE if they are different
+ *
+ * Programmer:  Quincey Koziol
+ *              Monday, November 21, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+compare_data(hid_t parent1, hid_t parent2, hid_t pid, hid_t tid, size_t nelmts,
+        const void *buf1, const void *buf2, hid_t obj_owner)
+{
+    size_t elmt_size;           /* Size of an element */
+
+    /* Check size of each element */
+    if((elmt_size = H5Tget_size(tid)) == 0) TEST_ERROR
+
+    /* If the type is a compound containing a vlen, loop over all elements for
+     * each compound member.  Compounds containing reference  are not supported
+     * yet. */
+    if((H5Tget_class(tid) == H5T_COMPOUND)
+            && (H5Tdetect_class(tid, H5T_VLEN) == TRUE)) {
+        hid_t           memb_id;    /* Member id */
+        const uint8_t   *memb1;     /* Pointer to current member */
+        const uint8_t   *memb2;     /* Pointer to current member */
+        int             nmembs;     /* Number of members */
+        size_t          memb_off;   /* Member offset */
+        size_t          memb_size;  /* Member size */
+        unsigned        memb_idx;   /* Member index */
+        size_t          elmt;       /* Current element */
+
+        /* Get number of members in compound */
+        if((nmembs = H5Tget_nmembers(tid)) < 0) TEST_ERROR
+
+        /* Loop over members */
+        for(memb_idx=0; memb_idx<(unsigned)nmembs; memb_idx++) {
+            /* Get member offset.  Note that we cannot check for an error here.
+             */
+            memb_off = H5Tget_member_offset(tid, memb_idx);
+
+            /* Get member id */
+            if((memb_id = H5Tget_member_type(tid, memb_idx)) < 0) TEST_ERROR
+
+            /* Get member size */
+            if((memb_size = H5Tget_size(memb_id)) == 0) TEST_ERROR
+
+            /* Set up pointers to member in the first element */
+            memb1 = (const uint8_t *)buf1 + memb_off;
+            memb2 = (const uint8_t *)buf2 + memb_off;
+
+            /* Check if this member contains (or is) a vlen */
+            if(H5Tget_class(memb_id) == H5T_VLEN) {
+                hid_t base_id;  /* vlen base type id */
+
+                /* Get base type of vlen datatype */
+                if((base_id = H5Tget_super(memb_id)) < 0) TEST_ERROR
+
+                /* Iterate over all elements, recursively calling this function
+                 * for each */
+                for(elmt=0; elmt<nelmts; elmt++) {
+                    /* Check vlen lengths */
+                    if(((const hvl_t *)((const void *)memb1))->len
+                            != ((const hvl_t *)((const void *)memb2))->len)
+                        TEST_ERROR
+
+                    /* Check vlen data */
+                    if(!compare_data(parent1, parent2, pid, base_id,
+                            ((const hvl_t *)((const void *)memb1))->len,
+                            ((const hvl_t *)((const void *)memb1))->p,
+                            ((const hvl_t *)((const void *)memb2))->p, obj_owner))
+                        TEST_ERROR
+
+                    /* Update member pointers */
+                    memb1 += elmt_size;
+                    memb2 += elmt_size;
+                } /* end for */
+            } else {
+                /* vlens cannot currently be nested below the top layer of a
+                 * compound */
+                HDassert(H5Tdetect_class(memb_id, H5T_VLEN) == FALSE);
+
+                /* Iterate over all elements, calling memcmp() for each */
+                for(elmt=0; elmt<nelmts; elmt++) {
+                    if(HDmemcmp(memb1, memb2, memb_size))
+                        TEST_ERROR
+
+                    /* Update member pointers */
+                    memb1 += elmt_size;
+                    memb2 += elmt_size;
+                } /* end for */
+            } /* end else */
+        } /* end for */
+    } else if(H5Tdetect_class(tid, H5T_VLEN) == TRUE) {
+        const hvl_t *vl_buf1, *vl_buf2; /* Aliases for buffers to compare */
+        hid_t base_tid;                 /* Base type of vlen datatype */
+        size_t u;                       /* Local index variable */
+
+        /* Check for "simple" vlen datatype */
+        if(H5Tget_class(tid) != H5T_VLEN) TEST_ERROR
+
+        /* Get base type of vlen datatype */
+        if((base_tid = H5Tget_super(tid)) < 0) TEST_ERROR
+
+        /* Loop over elements in buffers */
+        vl_buf1 = (const hvl_t *)buf1;
+        vl_buf2 = (const hvl_t *)buf2;
+        for(u = 0; u < nelmts; u++, vl_buf1++, vl_buf2++) {
+            /* Check vlen lengths */
+            if(vl_buf1->len != vl_buf2->len) TEST_ERROR
+
+            /* Check vlen data */
+            if(!compare_data(parent1, parent2, pid, base_tid, vl_buf1->len, vl_buf1->p, vl_buf2->p, obj_owner)) TEST_ERROR
+        } /* end for */
+
+        if(H5Tclose(base_tid) < 0) TEST_ERROR
+    } /* end if */
+    else if(H5Tdetect_class(tid, H5T_REFERENCE) == TRUE) {
+        size_t u;                       /* Local index variable */
+
+        /* Check for "simple" reference datatype */
+        if(H5Tget_class(tid) != H5T_REFERENCE) TEST_ERROR
+
+        /* Check for object or region reference */
+        if(H5Tequal(tid, H5T_STD_REF) > 0) {
+            const H5R_ref_t *ref_buf1, *ref_buf2;      /* Aliases for buffers to compare */
+
+            /* Loop over elements in buffers */
+            ref_buf1 = (const H5R_ref_t *)buf1;
+            ref_buf2 = (const H5R_ref_t *)buf2;
+            for(u = 0; u < nelmts; u++, ref_buf1++, ref_buf2++) {
+                hid_t obj1_id, obj2_id;         /* IDs for objects referenced */
+                H5O_type_t obj1_type, obj2_type; /* Types of objects referenced */
+
+                /* Check for types of objects handled */
+                if(H5Rget_obj_type3(ref_buf1, H5P_DEFAULT, &obj1_type) < 0) TEST_ERROR
+                if(H5Rget_obj_type3(ref_buf2, H5P_DEFAULT, &obj2_type) < 0) TEST_ERROR
+                if(obj1_type != obj2_type) TEST_ERROR
+
+                /* Open referenced objects */
+                if((obj1_id = H5Ropen_object(ref_buf1, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+                if((obj2_id = H5Ropen_object(ref_buf2, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+
+                /* break the infinite loop when the ref_object points to itself */
+                if(obj_owner > 0) {
+                    H5O_info_t oinfo1, oinfo2;
+
+                    if(H5Oget_info2(obj_owner, &oinfo1, H5O_INFO_BASIC) < 0) TEST_ERROR
+                    if(H5Oget_info2(obj1_id, &oinfo2, H5O_INFO_BASIC) < 0) TEST_ERROR
+                    if(H5F_addr_eq(oinfo1.addr, oinfo2.addr)) {
+                        if(H5Oclose(obj1_id) < 0) TEST_ERROR
+                        if(H5Oclose(obj2_id) < 0) TEST_ERROR
+                        return TRUE;
+                    }
+                }
+
+                /* Check for types of objects handled */
+                switch(obj1_type) {
+                    case H5O_TYPE_DATASET:
+                        if(compare_datasets(obj1_id, obj2_id, pid, NULL) != TRUE) TEST_ERROR
+                        break;
+
+                    case H5O_TYPE_GROUP:
+                        if(compare_groups(obj1_id, obj2_id, pid, -1, 0) != TRUE) TEST_ERROR
+                        break;
+
+                    case H5O_TYPE_NAMED_DATATYPE:
+                        if(H5Tequal(obj1_id, obj2_id) != TRUE) TEST_ERROR
+                        break;
+
+                    case H5O_TYPE_MAP:
+                        /* Maps not supported in native VOL connector */
+
+                    case H5O_TYPE_UNKNOWN:
+                    case H5O_TYPE_NTYPES:
+                    default:
+                        TEST_ERROR
+                } /* end switch */
+
+                /* Close objects */
+                if(H5Oclose(obj1_id) < 0) TEST_ERROR
+                if(H5Oclose(obj2_id) < 0) TEST_ERROR
+
+                if(H5Rget_type(ref_buf1) == H5R_DATASET_REGION2) {
+                    hid_t obj1_sid, obj2_sid;       /* Dataspace IDs for objects referenced */
+
+                    /* Get regions for referenced datasets */
+                    if((obj1_sid = H5Ropen_region(ref_buf1, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+                    if((obj2_sid = H5Ropen_region(ref_buf2, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+
+                    /* Check if dataspaces are the same shape */
+                    if(H5Sselect_shape_same(obj1_sid, obj2_sid) < 0) TEST_ERROR
+
+                    /* Close dataspaces */
+                    if(H5Sclose(obj1_sid) < 0) TEST_ERROR
+                    if(H5Sclose(obj2_sid) < 0) TEST_ERROR
+                } /* end if */
+            } /* end for */
+        } /* end if */
+        else
+            TEST_ERROR
+    } /* end else */
+    else
+        if(HDmemcmp(buf1, buf2, (elmt_size * nelmts))) TEST_ERROR
+
+    /* Data should be the same. :-) */
+    return TRUE;
+
+error:
+    return FALSE;
+} /* end compare_data() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    compare_datasets
+ *
+ * Purpose:     Compare two datasets to check that they are equal
+ *
+ * Return:    TRUE if datasets are equal/FALSE if they are different
+ *
+ * Programmer:  Quincey Koziol
+ *              Tuesday, October 25, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+compare_datasets(hid_t did, hid_t did2, hid_t pid, const void *wbuf)
+{
+    hid_t sid = -1, sid2 = -1;                  /* Dataspace IDs */
+    hid_t tid = -1, tid2 = -1;                  /* Datatype IDs */
+    hid_t dcpl = -1, dcpl2 = -1;                /* Dataset creation property list IDs */
+    size_t elmt_size;                           /* Size of datatype */
+    htri_t is_committed;                        /* If the datatype is committed */
+    htri_t is_committed2;                       /* If the datatype is committed */
+    int nfilters;                               /* Number of filters applied to dataset */
+    hssize_t nelmts;                            /* # of elements in dataspace */
+    void *rbuf = NULL;                          /* Buffer for reading raw data */
+    void *rbuf2 = NULL;                         /* Buffer for reading raw data */
+    H5D_space_status_t space_status;            /* Dataset's raw dataspace status */
+    H5D_space_status_t space_status2;           /* Dataset's raw dataspace status */
+
+    /* Check the datatypes are equal */
+
+    /* Open the datatype for the source dataset */
+    if((tid = H5Dget_type(did)) < 0) TEST_ERROR
+
+    /* Open the datatype for the destination dataset */
+    if((tid2 = H5Dget_type(did2)) < 0) TEST_ERROR
+
+    /* Check that both datatypes are committed/not committed */
+    if((is_committed = H5Tcommitted(tid)) < 0) TEST_ERROR
+    if((is_committed2 = H5Tcommitted(tid2)) < 0) TEST_ERROR
+    if(is_committed != is_committed2) TEST_ERROR
+
+    /* Compare the datatypes */
+    if(H5Tequal(tid, tid2) != TRUE) TEST_ERROR
+
+    /* Determine the size of datatype (for later) */
+    if((elmt_size = H5Tget_size(tid)) == 0) TEST_ERROR
+
+
+    /* Check the dataspaces are equal */
+
+    /* Open the dataspace for the source dataset */
+    if((sid = H5Dget_space(did)) < 0) TEST_ERROR
+
+    /* Open the dataspace for the destination dataset */
+    if((sid2 = H5Dget_space(did2)) < 0) TEST_ERROR
+
+    /* Compare the dataspaces */
+    if(H5Sextent_equal(sid, sid2) != TRUE) TEST_ERROR
+
+    /* Determine the number of elements in dataspace (for later) */
+    if((nelmts = H5Sget_simple_extent_npoints(sid)) < 0) TEST_ERROR
+
+
+    /* Check the dataset creation property lists are equal */
+
+    /* Open the dataset creation property list for the source dataset */
+    if((dcpl = H5Dget_create_plist(did)) < 0) TEST_ERROR
+
+    /* Open the dataset creation property list for the destination dataset */
+    if((dcpl2 = H5Dget_create_plist(did2)) < 0) TEST_ERROR
+
+    /* Compare the rest of the dataset creation property lists */
+    if(H5Pequal(dcpl, dcpl2) != TRUE) TEST_ERROR
+
+    /* Get the number of filters on dataset (for later) */
+    if((nfilters = H5Pget_nfilters(dcpl)) < 0) TEST_ERROR
+
+    /* close the source dataset creation property list */
+    if(H5Pclose(dcpl) < 0) TEST_ERROR
+
+    /* close the destination dataset creation property list */
+    if(H5Pclose(dcpl2) < 0) TEST_ERROR
+
+
+    /* Check the allocated storage is the same */
+
+    /* Check that the space allocation status is the same */
+    if(H5Dget_space_status(did, &space_status) < 0) TEST_ERROR
+    if(H5Dget_space_status(did2, &space_status2) < 0) TEST_ERROR
+    if(space_status != space_status2) TEST_ERROR
+
+    /* Check that the space used is the same */
+    /* (Don't check if the dataset is filtered (i.e. compressed, etc.) and
+     *  the datatype is VLEN, since the addresses for the vlen
+     *  data in each dataset will (probably) be different and the storage
+     *  size will thus vary)
+     */
+    if(!(nfilters > 0 && (H5Tdetect_class(tid, H5T_VLEN) ||
+            (H5Tdetect_class(tid, H5T_REFERENCE) && H5Tequal(tid, H5T_STD_REF))))) {
+        hsize_t storage_size = H5Dget_storage_size(did);        /* Dataset's raw data storage size */
+        hsize_t storage_size2 = H5Dget_storage_size(did2);      /* 2nd Dataset's raw data storage size */
+
+        if(storage_size != storage_size2) TEST_ERROR
+    } /* end if */
+
+    /* Check the raw data is equal */
+
+    /* Allocate & initialize space for the raw data buffers */
+    if((rbuf = HDcalloc( elmt_size, (size_t)nelmts)) == NULL) TEST_ERROR
+    if((rbuf2 = HDcalloc( elmt_size, (size_t)nelmts)) == NULL) TEST_ERROR
+
+    /* Read data from datasets */
+    if(H5Dread(did, tid, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf) < 0) TEST_ERROR
+    if(H5Dread(did2, tid2, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf2) < 0) TEST_ERROR
+
+    /* Check raw data read in against data written out */
+    if(wbuf) {
+        if(!compare_data(did, (hid_t)0, pid, tid, (size_t)nelmts, wbuf, rbuf, did)) TEST_ERROR
+        if(!compare_data(did2, (hid_t)0, pid, tid2, (size_t)nelmts, wbuf, rbuf2, did2)) TEST_ERROR
+    } /* end if */
+    /* Don't have written data, just compare data between the two datasets */
+    else
+        if(!compare_data(did, did2, pid, tid, (size_t)nelmts, rbuf, rbuf2, did)) TEST_ERROR
+
+    /* Reclaim vlen data, if necessary */
+    if(H5Tdetect_class(tid, H5T_VLEN) == TRUE || H5Tdetect_class(tid, H5T_REFERENCE) == TRUE)
+        if(H5Treclaim(tid, sid, H5P_DEFAULT, rbuf) < 0) TEST_ERROR
+    if(H5Tdetect_class(tid2, H5T_VLEN) == TRUE || H5Tdetect_class(tid2, H5T_REFERENCE) == TRUE)
+        if(H5Treclaim(tid2, sid2, H5P_DEFAULT, rbuf2) < 0) TEST_ERROR
+
+    /* Release raw data buffers */
+    HDfree(rbuf);
+    rbuf = NULL;
+    HDfree(rbuf2);
+    rbuf2 = NULL;
+
+    /* close the source dataspace */
+    if(H5Sclose(sid) < 0) TEST_ERROR
+
+    /* close the destination dataspace */
+    if(H5Sclose(sid2) < 0) TEST_ERROR
+
+    /* close the source datatype */
+    if(H5Tclose(tid) < 0) TEST_ERROR
+
+    /* close the destination datatype */
+    if(H5Tclose(tid2) < 0) TEST_ERROR
+
+
+    /* Check if the attributes are equal */
+    if(compare_std_attributes(did, did2, pid) != TRUE) TEST_ERROR
+
+
+    /* Datasets should be the same. :-) */
+    return TRUE;
+
+error:
+    H5E_BEGIN_TRY {
+        if(rbuf)
+            HDfree(rbuf);
+        if(rbuf2)
+            HDfree(rbuf2);
+        H5Pclose(dcpl2);
+        H5Pclose(dcpl);
+        H5Sclose(sid2);
+        H5Sclose(sid);
+        H5Tclose(tid2);
+        H5Tclose(tid);
+    } H5E_END_TRY;
+    return FALSE;
+} /* end compare_datasets() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    compare_groups
+ *
+ * Purpose:     Compare two groups to check that they are "equal"
+ *
+ * Return:    TRUE if group are equal/FALSE if they are different
+ *
+ * Programmer:  Quincey Koziol
+ *              Monday, October 31, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+compare_groups(hid_t gid, hid_t gid2, hid_t pid, int depth, unsigned copy_flags)
+{
+    H5G_info_t ginfo;           /* Group info struct */
+    H5G_info_t ginfo2;          /* Group info struct */
+    hsize_t idx;                /* Index over the objects in group */
+    unsigned cpy_flags;         /* Object copy flags */
+
+    /* Retrieve the object copy flags from the property list, if it's non-DEFAULT */
+    if(pid != H5P_DEFAULT) {
+        if(H5Pget_copy_object(pid, &cpy_flags) < 0) TEST_ERROR
+    } /* end if */
+    else
+        cpy_flags = 0;
+
+    /* Check if both groups have the same # of objects */
+    if(H5Gget_info(gid, &ginfo) < 0) TEST_ERROR
+    if(H5Gget_info(gid2, &ginfo2) < 0) TEST_ERROR
+    if((cpy_flags & H5O_COPY_SHALLOW_HIERARCHY_FLAG) && depth == 0) {
+        if(ginfo2.nlinks != 0) TEST_ERROR
+    } /* end if */
+    else {
+        if(ginfo.nlinks != ginfo2.nlinks) TEST_ERROR
+    } /* end if */
+
+    /* Check contents of groups */
+    if(ginfo2.nlinks > 0) {
+        char objname[NAME_BUF_SIZE];            /* Name of object in group */
+        char objname2[NAME_BUF_SIZE];           /* Name of object in group */
+        H5L_info_t linfo;                       /* Link information */
+        H5L_info_t linfo2;                      /* Link information */
+
+        /* Loop over contents of groups */
+        for(idx = 0; idx < ginfo.nlinks; idx++) {
+            /* Check name of objects */
+            if(H5Lget_name_by_idx(gid, ".", H5_INDEX_NAME, H5_ITER_INC, idx, objname, (size_t)NAME_BUF_SIZE, H5P_DEFAULT) < 0) TEST_ERROR
+            if(H5Lget_name_by_idx(gid2, ".", H5_INDEX_NAME, H5_ITER_INC, idx, objname2, (size_t)NAME_BUF_SIZE, H5P_DEFAULT) < 0) TEST_ERROR
+            if(HDstrcmp(objname, objname2)) TEST_ERROR
+
+            /* Get link info */
+            if(H5Lget_info(gid, objname, &linfo, H5P_DEFAULT) < 0) TEST_ERROR
+            if(H5Lget_info(gid2, objname2, &linfo2, H5P_DEFAULT) < 0) TEST_ERROR
+            if(linfo.type != linfo2.type) TEST_ERROR
+
+            /* Extra checks for "real" objects */
+            if(linfo.type == H5L_TYPE_HARD) {
+                hid_t oid, oid2;                /* IDs of objects within group */
+                H5O_info_t oinfo, oinfo2;       /* Object info */
+
+                /* Compare some pieces of the object info */
+                if(H5Oget_info_by_name2(gid, objname, &oinfo, H5O_INFO_BASIC|H5O_INFO_HDR, H5P_DEFAULT) < 0) TEST_ERROR
+                if(H5Oget_info_by_name2(gid2, objname2, &oinfo2, H5O_INFO_BASIC|H5O_INFO_HDR, H5P_DEFAULT) < 0) TEST_ERROR
+
+                if(oinfo.type != oinfo2.type) TEST_ERROR
+                if(oinfo.rc != oinfo2.rc) TEST_ERROR
+
+                /* If NULL messages are preserved, the number of messages
+                 * should be the same in the destination.
+                 * Otherwise, it should simply be true that the number
+                 * of messages hasn't increased.
+                 */
+                 if(H5O_COPY_PRESERVE_NULL_FLAG & copy_flags) {
+                    if(oinfo.hdr.nmesgs != oinfo2.hdr.nmesgs)
+                        ;
+                    else
+                        if(oinfo.hdr.nmesgs < oinfo2.hdr.nmesgs) TEST_ERROR
+                 }
+
+                /* Check for object already having been compared */
+                if(addr_lookup(&oinfo))
+                    continue;
+                else
+                    addr_insert(&oinfo);
+
+                /* Open objects */
+                if((oid = H5Oopen(gid, objname, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+                if((oid2 = H5Oopen(gid2, objname2, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+
+                /* Compare objects within group */
+                switch(oinfo.type) {
+                    case H5O_TYPE_GROUP:
+                        /* Compare groups */
+                        if(compare_groups(oid, oid2, pid, depth - 1, copy_flags) != TRUE) TEST_ERROR
+                        break;
+
+                    case H5O_TYPE_DATASET:
+                        /* Compare datasets */
+                        if(compare_datasets(oid, oid2, pid, NULL) != TRUE) TEST_ERROR
+                        break;
+
+                    case H5O_TYPE_NAMED_DATATYPE:
+                        /* Compare datatypes */
+                        if(H5Tequal(oid, oid2) != TRUE) TEST_ERROR
+                        break;
+
+                    case H5O_TYPE_MAP:
+                        HDassert(0 && "maps not supported in native VOL connector");
+
+                    case H5O_TYPE_UNKNOWN:
+                    case H5O_TYPE_NTYPES:
+                    default:
+                        HDassert(0 && "Unknown type of object");
+                        break;
+                } /* end switch */
+
+                /* Close objects */
+                if(H5Oclose(oid) < 0) TEST_ERROR
+                if(H5Oclose(oid2) < 0) TEST_ERROR
+            } /* end if */
+            else {
+                /* Check that both links are the same size */
+                if(linfo.u.val_size != linfo2.u.val_size) TEST_ERROR
+
+                /* Compare link values */
+                if(linfo.type == H5L_TYPE_SOFT ||
+                        (linfo.type >= H5L_TYPE_UD_MIN && linfo.type <= H5L_TYPE_MAX)) {
+                    char linkval[NAME_BUF_SIZE];            /* Link value */
+                    char linkval2[NAME_BUF_SIZE];           /* Link value */
+
+                    /* Get link values */
+                    HDassert(linfo.u.val_size <= NAME_BUF_SIZE);
+                    if(H5Lget_val(gid, objname, linkval, (size_t)NAME_BUF_SIZE, H5P_DEFAULT) < 0) TEST_ERROR
+                    if(H5Lget_val(gid2, objname2, linkval2, (size_t)NAME_BUF_SIZE, H5P_DEFAULT) < 0) TEST_ERROR
+
+                    /* Compare link data */
+                    if(HDmemcmp(linkval, linkval2, linfo.u.val_size)) TEST_ERROR
+                } /* end else-if */
+                else {
+HDassert(0 && "Unknown type of link");
+                } /* end else */
+            } /* end else */
+        } /* end for */
+    } /* end if */
+
+    /* Check if the attributes are equal */
+    if(compare_std_attributes(gid, gid2, pid) != TRUE) TEST_ERROR
+
+    /* Groups should be the same. :-) */
+    return TRUE;
+
+error:
+    H5E_BEGIN_TRY {
+    } H5E_END_TRY;
+    return FALSE;
+} /* end compare_groups() */
+
+/*-------------------------------------------------------------------------
+ * Function:    test_copy_option
+ *
+ * Purpose:     Create a group in SRC file and copy it to DST file
+ *
+ * Return:      Success:        0
+ *              Failure:        number of errors
+ *
+ * Programmer:  Peter Cao
+ *               March 11, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+test_copy_option(hid_t fcpl_src, hid_t fcpl_dst, hid_t src_fapl, hid_t dst_fapl,
+    unsigned flag, hbool_t crt_intermediate_grp, const char* test_desciption)
+{
+    hid_t fid_src = -1, fid_dst = -1, fid_ext = -1; /* File IDs */
+    hid_t sid = -1;                             /* Dataspace ID */
+    hid_t did = -1;                             /* Dataset ID */
+    hid_t gid=-1, gid2=-1, gid_ref=-1;          /* Group IDs */
+    hid_t gid_sub=-1, gid_sub_sub=-1;           /* Sub-group ID */
+    hid_t pid=-1, lcpl_id=-1;            /* Property IDs */
+    unsigned cpy_flags;                         /* Object copy flags */
+    int depth = -1;                             /* Copy depth */
+    hsize_t dim2d[2];
+    int buf[DIM_SIZE_1][DIM_SIZE_2];
+    int i, j;
+    char src_filename[NAME_BUF_SIZE];
+    char dst_filename[NAME_BUF_SIZE];
+
+    TESTING(test_desciption);
+
+    /* set initial data values */
+    for (i=0; i<DIM_SIZE_1; i++)
+        for (j=0; j<DIM_SIZE_2; j++)
+            buf[i][j] = 10000 + 100*i+j;
+
+    /* Initialize the filenames */
+    h5_fixname(FILENAME[0], src_fapl, src_filename, sizeof src_filename);
+    h5_fixname(FILENAME[1], dst_fapl, dst_filename, sizeof dst_filename);
+
+    /* Reset file address checking info */
+    addr_reset();
+
+    /* create source file */
+    if((fid_src = H5Fcreate(src_filename, H5F_ACC_TRUNC, fcpl_src, src_fapl)) < 0) TEST_ERROR
+
+    /* create group at the SRC file */
+    if((gid = H5Gcreate2(fid_src, NAME_GROUP_TOP, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+
+    /* attach attributes to the group */
+    if(test_copy_attach_attributes(gid, H5T_NATIVE_INT) < 0) TEST_ERROR
+
+    /* Set dataspace dimensions */
+    dim2d[0]=DIM_SIZE_1;
+    dim2d[1]=DIM_SIZE_2;
+
+    /* create dataspace */
+    if((sid = H5Screate_simple(2, dim2d, NULL)) < 0) TEST_ERROR
+
+    /* add a dataset to the top group */
+    if((did = H5Dcreate2(gid, NAME_DATASET_SIMPLE, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Dwrite(did, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf) < 0) TEST_ERROR
+    if(H5Dclose(did) < 0) TEST_ERROR
+
+    /* create a sub-group */
+    if((gid_sub = H5Gcreate2(fid_src, NAME_GROUP_SUB, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+
+    /* add a dataset to the sub group */
+    if((did = H5Dcreate2(gid_sub, NAME_DATASET_SIMPLE, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Dwrite(did, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf) < 0) TEST_ERROR
+    if(H5Dclose(did) < 0) TEST_ERROR
+
+    /* create sub-sub-group */
+    if((gid_sub_sub = H5Gcreate2(gid_sub, NAME_GROUP_SUB_SUB2, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+
+    /* add a dataset to the sub sub group */
+    if((did = H5Dcreate2(gid_sub_sub, NAME_DATASET_SIMPLE, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if(H5Dwrite(did, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf) < 0) TEST_ERROR
+
+    /* close dataset */
+    if(H5Dclose(did) < 0) TEST_ERROR
+
+    /* close dataspace */
+    if(H5Sclose(sid) < 0) TEST_ERROR
+
+    if(H5Gclose(gid_sub_sub) < 0) TEST_ERROR
+
+    if(H5Gclose(gid_sub) < 0) TEST_ERROR
+
+    /* close the group */
+    if(H5Gclose(gid) < 0) FAIL_STACK_ERROR
+
+    if((flag & H5O_COPY_EXPAND_SOFT_LINK_FLAG) > 0) {
+        /* Create group to copy */
+        if((gid = H5Gcreate2(fid_src, NAME_GROUP_LINK, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+        if(H5Lcreate_soft(NAME_DATASET_SUB_SUB, fid_src, NAME_LINK_SOFT, H5P_DEFAULT, H5P_DEFAULT) < 0) FAIL_STACK_ERROR
+        if(H5Lcreate_soft("nowhere", fid_src, NAME_LINK_SOFT_DANGLE, H5P_DEFAULT, H5P_DEFAULT) < 0) FAIL_STACK_ERROR
+        if(H5Gclose(gid) < 0) FAIL_STACK_ERROR
+
+        /* Create group to compare with */
+        if((gid = H5Gcreate2(fid_src, NAME_GROUP_LINK2, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+        if(H5Lcreate_hard(fid_src, NAME_DATASET_SUB_SUB, H5L_SAME_LOC, NAME_LINK_SOFT2, H5P_DEFAULT, H5P_DEFAULT) < 0) FAIL_STACK_ERROR
+        if(H5Lcreate_soft("nowhere", fid_src, NAME_LINK_SOFT_DANGLE2, H5P_DEFAULT, H5P_DEFAULT) < 0) FAIL_STACK_ERROR
+        if(H5Gclose(gid) < 0) FAIL_STACK_ERROR
+    } /* end if */
+
+    if((flag & H5O_COPY_EXPAND_EXT_LINK_FLAG) > 0) {
+        char    ext_filename[NAME_BUF_SIZE];
+
+        h5_fixname(FILENAME[2], src_fapl, ext_filename, sizeof ext_filename);
+
+        /* Create the external file and dataset */
+        if((fid_ext = H5Fcreate(ext_filename, H5F_ACC_TRUNC, fcpl_src, src_fapl)) < 0) TEST_ERROR
+        if((sid = H5Screate_simple(2, dim2d, NULL)) < 0) TEST_ERROR
+        if((did = H5Dcreate2(fid_ext, NAME_DATASET_SIMPLE, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+        if(H5Dwrite(did, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf) < 0) TEST_ERROR
+        if(H5Dclose(did) < 0) TEST_ERROR
+        if(H5Fclose(fid_ext) < 0) TEST_ERROR
+
+        /* Create group to copy */
+        if(!(flag & H5O_COPY_EXPAND_SOFT_LINK_FLAG)) {
+            if((gid = H5Gcreate2(fid_src, NAME_GROUP_LINK, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+        } /* end if */
+        else
+            if((gid = H5Gopen2(fid_src, NAME_GROUP_LINK, H5P_DEFAULT)) < 0) TEST_ERROR
+        if(H5Lcreate_external(ext_filename, NAME_DATASET_SIMPLE, fid_src, NAME_LINK_EXTERN, H5P_DEFAULT, H5P_DEFAULT) < 0) TEST_ERROR
+        if(H5Lcreate_external("no_file", "no_object", fid_src, NAME_LINK_EXTERN_DANGLE, H5P_DEFAULT, H5P_DEFAULT) < 0) TEST_ERROR
+        if(H5Gclose(gid) < 0) TEST_ERROR
+
+        /* Create group to compare with */
+        if(!(flag & H5O_COPY_EXPAND_SOFT_LINK_FLAG)) {
+            if((gid = H5Gcreate2(fid_src, NAME_GROUP_LINK2, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+        } /* end if */
+        else
+            if((gid = H5Gopen2(fid_src, NAME_GROUP_LINK2, H5P_DEFAULT)) < 0) TEST_ERROR
+        if((did = H5Dcreate2(fid_src, NAME_LINK_EXTERN2, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+        if(H5Dwrite(did, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf) < 0) TEST_ERROR
+        if(H5Lcreate_external("no_file", "no_object", fid_src, NAME_LINK_EXTERN_DANGLE2, H5P_DEFAULT, H5P_DEFAULT) < 0) TEST_ERROR
+        if(H5Dclose(did) < 0) TEST_ERROR
+        if(H5Gclose(gid) < 0) TEST_ERROR
+
+        /* Close dataspace */
+        if(H5Sclose(sid) < 0) TEST_ERROR
+    } /* end if */
+
+    if((flag & H5O_COPY_EXPAND_REFERENCE_FLAG) > 0) {
+        if((gid_ref = H5Gcreate2(fid_src, NAME_GROUP_REF, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+
+        /* create an attribute of new object references */
+        if(attach_ref_attr(fid_src, gid_ref) < 0) TEST_ERROR
+
+        /* create an attribute of region references */
+        if(attach_reg_ref_attr(fid_src, gid_ref) < 0) TEST_ERROR
+
+        /* create a dataset of region references */
+        if(create_reg_ref_dataset(fid_src, gid_ref) < 0) TEST_ERROR
+
+        /* Close group holding reference objects */
+        if(H5Gclose(gid_ref) < 0) TEST_ERROR
+    } /* end if */
+
+    /* close the SRC file */
+    if(H5Fclose(fid_src) < 0) TEST_ERROR
+
+    /* open the source file with read-only */
+    /* (except when expanding soft links */
+    if((flag & H5O_COPY_EXPAND_SOFT_LINK_FLAG) > 0) {
+        if((fid_src = H5Fopen(src_filename, H5F_ACC_RDWR, src_fapl)) < 0) TEST_ERROR
+    } /* end if */
+    else
+        if((fid_src = H5Fopen(src_filename, H5F_ACC_RDONLY, src_fapl)) < 0) TEST_ERROR
+
+    /* create destination file */
+    if((fid_dst = H5Fcreate(dst_filename, H5F_ACC_TRUNC, fcpl_dst, dst_fapl)) < 0) TEST_ERROR
+
+    /* Create an uncopied object in destination file so that addresses in source and destination
+       files aren't the same */
+    if(H5Gclose(H5Gcreate2(fid_dst, NAME_GROUP_UNCOPIED, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+
+    /* create property to pass copy options */
+    if((pid = H5Pcreate(H5P_OBJECT_COPY)) < 0) TEST_ERROR
+
+    /* set options for object copy */
+    if(H5Pset_copy_object(pid, flag) < 0) TEST_ERROR
+
+    /* Verify object copy flags */
+    if(H5Pget_copy_object(pid, &cpy_flags) < 0) TEST_ERROR
+    if(cpy_flags != flag) TEST_ERROR
+
+    /* copy the group from SRC to DST */
+    if(crt_intermediate_grp) {
+        /* Create link creation plist to pass in intermediate group creation */
+        if((lcpl_id = H5Pcreate(H5P_LINK_CREATE)) < 0) TEST_ERROR
+        if(H5Pset_create_intermediate_group(lcpl_id, TRUE) < 0) TEST_ERROR
+
+        if(H5Ocopy(fid_src, NAME_GROUP_TOP, fid_dst, "/new_g0/new_g00", pid, lcpl_id) < 0) TEST_ERROR
+
+        if(H5Pclose(lcpl_id) < 0) TEST_ERROR
+
+        /* open the group for copy */
+        if((gid = H5Gopen2(fid_src, NAME_GROUP_TOP, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+
+        /* open the destination group */
+        if((gid2 = H5Gopen2(fid_dst, "/new_g0/new_g00", H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+
+    } else if(((flag & H5O_COPY_EXPAND_SOFT_LINK_FLAG) > 0)
+            || ((flag & H5O_COPY_EXPAND_EXT_LINK_FLAG) > 0)) {
+        if(H5Ocopy(fid_src, NAME_GROUP_LINK, fid_dst, NAME_GROUP_LINK, pid, H5P_DEFAULT) < 0) TEST_ERROR
+
+        if((flag & H5O_COPY_EXPAND_SOFT_LINK_FLAG) > 0)
+            /* Unlink dataset to copy from original location */
+            /* (So group comparison works properly) */
+            if(H5Ldelete(fid_src, NAME_DATASET_SUB_SUB, H5P_DEFAULT) < 0) FAIL_STACK_ERROR
+
+        /* open the group for copy */
+        if((gid = H5Gopen2(fid_src, NAME_GROUP_LINK2, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+
+        /* open the destination group */
+        if((gid2 = H5Gopen2(fid_dst, NAME_GROUP_LINK, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+
+    } else if(flag & (H5O_COPY_WITHOUT_ATTR_FLAG | H5O_COPY_PRESERVE_NULL_FLAG)) {
+        if(H5Ocopy(fid_src, NAME_GROUP_TOP, fid_dst, NAME_GROUP_TOP, pid, H5P_DEFAULT) < 0) TEST_ERROR
+
+        /* open the group for copy */
+        if((gid = H5Gopen2(fid_src, NAME_GROUP_TOP, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+
+        /* open the destination group */
+        if((gid2 = H5Gopen2(fid_dst, NAME_GROUP_TOP, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+    } else if(flag & H5O_COPY_SHALLOW_HIERARCHY_FLAG) {
+        if(H5Ocopy(fid_src, NAME_GROUP_TOP, fid_dst, NAME_GROUP_TOP, pid, H5P_DEFAULT) < 0) TEST_ERROR
+
+        /* open the group for copy */
+        if((gid = H5Gopen2(fid_src, NAME_GROUP_TOP, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+
+        /* open the destination group */
+        if((gid2 = H5Gopen2(fid_dst, NAME_GROUP_TOP, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+
+        /* Set the copy depth */
+        depth = 1;
+    } else if((flag & H5O_COPY_EXPAND_REFERENCE_FLAG) > 0) {
+        if(H5Ocopy(fid_src, NAME_GROUP_REF, fid_dst, NAME_GROUP_REF, pid, H5P_DEFAULT) < 0) TEST_ERROR
+
+        /* open the group for copy */
+        if((gid = H5Gopen2(fid_src, NAME_GROUP_REF, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+
+        /* open the destination group */
+        if((gid2 = H5Gopen2(fid_dst, NAME_GROUP_REF, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
+    } else {
+        /* Unknown flag */
+        TEST_ERROR
+    } /* end else */
+
+    /* Check if the groups are equal */
+    if(compare_groups(gid, gid2, pid, depth, flag) != TRUE) TEST_ERROR
+    if(H5Gclose(gid2) < 0) TEST_ERROR
+    if(H5Gclose(gid) < 0) TEST_ERROR
+
+    /* close the SRC file */
+    if(H5Fclose(fid_src) < 0) TEST_ERROR
+
+    /* close the DST file */
+    if(H5Fclose(fid_dst) < 0) TEST_ERROR
+
+    /* close properties */
+    if(H5Pclose(pid) < 0) TEST_ERROR
+
+    PASSED();
+    return 0;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Pclose(lcpl_id);
+        H5Pclose(pid);
+        H5Sclose(sid);
+        H5Dclose(did);
+        H5Gclose(gid_ref);
+        H5Gclose(gid_sub);
+        H5Gclose(gid2);
+        H5Gclose(gid);
+        H5Fclose(fid_dst);
+        H5Fclose(fid_src);
+        H5Fclose(fid_ext);
+    } H5E_END_TRY;
+    return 1;
+} /* end test_copy_option */
+
+/*-------------------------------------------------------------------------
+ * Function:    main
+ *
+ * Purpose:     Test H5Ocopy()
+ *
+ *              Tests a number of cases: messages can be stored in the
+ *              new or old format, messages can be shared in either,
+ *              both, or neither of the source and destination files.
+ *
+ * Return:      EXIT_SUCCESS/EXIT_FAILURE
+ *
+ * Programmer:  Peter Cao
+ *              Friday, September 30, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+main(void)
+{
+    int     nerrors = 0;
+    hid_t    fapl, fapl2;
+    hid_t   fcpl_shared, ocpl;
+    unsigned    max_compact, min_dense;
+    int     configuration;  /* Configuration of tests. */
+    int    ExpressMode;
+    hbool_t same_file;  /* Whether to run tests that only use one file */
+
+    /* Setup */
+    h5_reset();
+    fapl = h5_fileaccess();
+
+    ExpressMode = GetTestExpress();
+    if (ExpressMode > 1)
+        HDprintf("***Express test mode on.  Some tests may be skipped\n");
+
+    /* Copy the file access property list */
+    if((fapl2 = H5Pcopy(fapl)) < 0) TEST_ERROR
+
+    /* Set the "use the latest version of the format" bounds for creating objects in the file */
+    if(H5Pset_libver_bounds(fapl2, H5F_LIBVER_LATEST, H5F_LIBVER_LATEST) < 0) TEST_ERROR
+
+    /* Create an FCPL with sharing enabled */
+    if((fcpl_shared = H5Pcreate(H5P_FILE_CREATE)) < 0) TEST_ERROR
+    if(H5Pset_shared_mesg_nindexes(fcpl_shared, 1) < 0) TEST_ERROR
+    if(H5Pset_shared_mesg_index(fcpl_shared, 0, H5O_SHMESG_ALL_FLAG, 10) < 0) TEST_ERROR
+
+    /* Obtain the default attribute storage phase change values */
+    if((ocpl = H5Pcreate(H5P_OBJECT_CREATE)) < 0) TEST_ERROR
+    if(H5Pget_attr_phase_change(ocpl, &max_compact, &min_dense) < 0) TEST_ERROR
+    if(H5Pclose(ocpl) < 0) TEST_ERROR
+
+    /* Test in all configurations */
+    for(configuration = 0; configuration <= MAX_CONFIGURATION; configuration++) {
+        hid_t src_fapl;
+        hid_t dst_fapl;
+        hid_t fcpl_src;
+        hid_t fcpl_dst;
+
+        /* Start with same_file == TRUE.  Use source file settings for these
+         * tests.  Don't run with a non-default destination file setting, as
+         * destination settings have no effect. */
+        same_file = TRUE;
+
+        /* No need to test dense attributes with old format */
+        if(!(configuration & CONFIG_SRC_NEW_FORMAT) && (configuration & CONFIG_DENSE))
+            continue;
+
+        /* TODO Region references currently do not support copy from new format to old format
+         * (this may be fixed once H5Sencode/decode and H5CXis fixed) */
+        if((configuration & CONFIG_SRC_NEW_FORMAT) && !(configuration & CONFIG_DST_NEW_FORMAT))
+            continue;
+
+        /* Test with and without shared messages */
+        if(configuration & CONFIG_SHARE_SRC) {
+            HDputs("\nTesting with shared src messages:");
+            fcpl_src = fcpl_shared;
+        }
+        else {
+            HDputs("\nTesting without shared src messages:");
+            fcpl_src = H5P_DEFAULT;
+        }
+        if(configuration & CONFIG_SHARE_DST) {
+            HDputs("Testing with shared dst messages:");
+            fcpl_dst = fcpl_shared;
+            same_file = FALSE;
+        }
+        else {
+            HDputs("Testing without shared dst messages:");
+            fcpl_dst = H5P_DEFAULT;
+        }
+
+        /* Set the FAPL for the source file's type of format */
+        if(configuration & CONFIG_SRC_NEW_FORMAT) {
+            HDputs("Testing with latest format for source file:");
+            src_fapl = fapl2;
+
+            /* Test with and without dense attributes */
+            if(configuration & CONFIG_DENSE) {
+                HDputs("Testing with dense attributes:");
+                num_attributes_g = max_compact + 1;
+            }
+            else {
+                HDputs("Testing without dense attributes:");
+                num_attributes_g = MAX(min_dense, 2) - 2;
+            }
+        } /* end if */
+        else {
+            HDputs("Testing with oldest file format for source file:");
+            src_fapl = fapl;
+            num_attributes_g = 4;
+        } /* end else */
+
+        /* Set the FAPL for the destination file's type of format */
+        if(configuration & CONFIG_DST_NEW_FORMAT) {
+            HDputs("Testing with latest format for destination file:");
+            dst_fapl = fapl2;
+            same_file = FALSE;
+        } /* end if */
+        else {
+            HDputs("Testing with oldest file format for destination file:");
+            dst_fapl = fapl;
+        } /* end else */
+
+        /* The tests... */
+        nerrors += test_copy_option(fcpl_src, fcpl_dst, src_fapl, dst_fapl,
+                    H5O_COPY_EXPAND_REFERENCE_FLAG,
+                    FALSE, "H5Ocopy(): expand object reference");
+    } /* end for */
+
+    /* Reset file address checking info */
+    addr_reset();
+
+    /* Verify symbol table messages are cached */
+    nerrors += (h5_verify_cached_stabs(FILENAME, fapl) < 0 ? 1 : 0);
+
+    /* Results */
+    if(nerrors) {
+        HDprintf("***** %d OBJECT COPY TEST%s FAILED! *****\n",
+                nerrors, (1 == nerrors ? "" : "S"));
+        HDexit(EXIT_FAILURE);
+    } /* end if */
+
+    HDputs ("All object copying tests passed.");
+
+    /* close property list.
+     * NOTE: if this property list is not closed and the test is
+     *          run with the split or multi driver, an interesting
+     *          problem is exposed in the property list shutdown code.
+     *
+     *          Namely, since the split/multi driver copies property
+     *          lists for internal use, there's a (high) chance that
+     *          leaving the FAPL open and having the library's shutdown
+     *          code close it will cause the underlying property lists
+     *          to be cleaned up first, causing the actual property list
+     *          close operation to fail (since it won't be able to close
+     *          the already closed underlying property list).
+     *
+     *          The could be addressed by converting the split/multi to
+     *          use non-public API routines, or putting some way into the
+     *          public H5I routines to indicate ordering at shutdown.
+     *
+     *          For now, we just make certain to close the property list.
+     *          (QAK - 2016/04/06)
+     *
+     */
+    H5Pclose(fapl2);
+
+    h5_cleanup(FILENAME, fapl);
+
+    HDexit(EXIT_SUCCESS);
+
+error:
+    HDexit(EXIT_FAILURE);
+} /* main */
+
diff --git a/test/testhdf5.c b/test/testhdf5.c
index e136086..72acf6c 100644
--- a/test/testhdf5.c
+++ b/test/testhdf5.c
@@ -57,7 +57,8 @@ main(int argc, char *argv[])
     AddTest("attr", test_attr, cleanup_attr,  "Attributes", NULL);
     AddTest("select", test_select, cleanup_select,  "Selections", NULL);
     AddTest("time", test_time, cleanup_time,  "Time Datatypes", NULL);
-    AddTest("reference", test_reference, cleanup_reference,  "References", NULL);
+    AddTest("ref_deprec", test_reference_deprec, cleanup_reference_deprec,  "Deprecated References", NULL);
+    AddTest("ref", test_reference, cleanup_reference,  "References", NULL);
     AddTest("vltypes", test_vltypes, cleanup_vltypes,  "Variable-Length Datatypes", NULL);
     AddTest("vlstrings", test_vlstrings, cleanup_vlstrings,  "Variable-Length Strings", NULL);
     AddTest("iterate", test_iterate, cleanup_iterate,  "Group & Attribute Iteration", NULL);
diff --git a/test/testhdf5.h b/test/testhdf5.h
index ef3b784..6b13cae 100644
--- a/test/testhdf5.h
+++ b/test/testhdf5.h
@@ -192,6 +192,7 @@ void test_attr(void);
 void test_select(void);
 void test_time(void);
 void test_reference(void);
+void test_reference_deprec(void);
 void test_vltypes(void);
 void test_vlstrings(void);
 void test_iterate(void);
@@ -215,6 +216,7 @@ void cleanup_attr(void);
 void cleanup_select(void);
 void cleanup_time(void);
 void cleanup_reference(void);
+void cleanup_reference_deprec(void);
 void cleanup_vltypes(void);
 void cleanup_vlstrings(void);
 void cleanup_iterate(void);
diff --git a/test/trefer.c b/test/trefer.c
index 7158984..7d87ea9 100644
--- a/test/trefer.c
+++ b/test/trefer.c
@@ -21,9 +21,16 @@
 
 #include "testhdf5.h"
 
-#define FILE1    "trefer1.h5"
-#define FILE2    "trefer2.h5"
-#define FILE3    "trefer3.h5"
+#define FILE_REF_PARAM      "trefer_param.h5"
+#define FILE_REF_OBJ        "trefer_obj.h5"
+#define FILE_REF_REG        "trefer_reg.h5"
+#define FILE_REF_REG_1D     "trefer_reg_1d.h5"
+#define FILE_REF_OBJ_DEL    "trefer_obj_del.h5"
+#define FILE_REF_GRP        "trefer_grp.h5"
+#define FILE_REF_ATTR       "trefer_attr.h5"
+#define FILE_REF_EXT1       "trefer_ext1.h5"
+#define FILE_REF_EXT2       "trefer_ext2.h5"
+#define FILE_REF_COMPAT     "trefer_compat.h5"
 
 /* 1-D dataset with fixed dimensions */
 #define SPACE1_RANK    1
@@ -55,6 +62,10 @@ typedef struct s1_t {
 #define DSETNAME2       "dset2"
 #define NAME_SIZE       16
 
+#define MAX_ITER_CREATE 1000
+#define MAX_ITER_WRITE  MAX_ITER_CREATE
+#define MAX_ITER_READ   MAX_ITER_CREATE
+
 
 /****************************************************************
 **
@@ -65,47 +76,57 @@ typedef struct s1_t {
 static void
 test_reference_params(void)
 {
-    hid_t       fid1;       /* HDF5 File IDs        */
-    hid_t       dataset,    /* Dataset ID           */
-                dset2;      /* Dereferenced dataset ID */
-    hid_t       group;      /* Group ID             */
-    hid_t       sid1;       /* Dataspace ID         */
-    hid_t       tid1;       /* Datatype ID          */
-    hid_t       dapl_id;    /* Dataset access property list */
+    hid_t       fid1;       /* HDF5 File IDs                    */
+    hid_t       dataset,    /* Dataset ID                       */
+                dset2;      /* Dereferenced dataset ID          */
+    hid_t       group;      /* Group ID                         */
+    hid_t       attr;       /* Attribute ID                     */
+    hid_t       sid1;       /* Dataspace ID                     */
+    hid_t       tid1;       /* Datatype ID                      */
+    hid_t       aapl_id;    /* Attribute access property list   */
+    hid_t       dapl_id;    /* Dataset access property list     */
     hsize_t     dims1[] = {SPACE1_DIM1};
-    hobj_ref_t *wbuf,       /* buffer to write to disk */
-               *rbuf,       /* buffer read from disk */
-               *tbuf;       /* temp. buffer read from disk */
+    H5R_ref_t     *wbuf,       /* buffer to write to disk          */
+               *rbuf,       /* buffer read from disk            */
+               *tbuf;       /* temp. buffer read from disk      */
+    H5R_type_t  type;       /* Reference type                   */
     unsigned   *tu32;       /* Temporary pointer to uint32 data */
-    int         i;          /* counting variables */
-    const char *write_comment = "Foo!"; /* Comments for group */
-    hid_t    ret_id;        /* Generic hid_t return value    */
-    ssize_t     name_size;  /* Size of reference name */
-    herr_t      ret;        /* Generic return value     */
+    int         i;          /* Counters                         */
+    const char *write_comment = "Foo!"; /* Comments for group   */
+    hid_t       ret_id;     /* Generic hid_t return value       */
+    ssize_t     name_size;  /* Size of reference name           */
+    herr_t      ret;        /* Generic return value             */
 
     /* Output message about test being performed */
     MESSAGE(5, ("Testing Reference Parameters\n"));
 
     /* Allocate write & read buffers */
-    wbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
-    rbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
-    tbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
+    wbuf = (H5R_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(H5R_ref_t)), SPACE1_DIM1);
+    rbuf = (H5R_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(H5R_ref_t)), SPACE1_DIM1);
+    tbuf = (H5R_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(H5R_ref_t)), SPACE1_DIM1);
+
+    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
+        *tu32++ = (unsigned)i * 3;
 
     /* Create file */
-    fid1 = H5Fcreate(FILE1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(fid1, FAIL, "H5Fcreate");
+    fid1 = H5Fcreate(FILE_REF_PARAM, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fcreate");
 
     /* Create dataspace for datasets */
     sid1 = H5Screate_simple(SPACE1_RANK, dims1, NULL);
-    CHECK(sid1, FAIL, "H5Screate_simple");
+    CHECK(sid1, H5I_INVALID_HID, "H5Screate_simple");
+
+    /* Create attribute access property list */
+    aapl_id = H5Pcreate(H5P_ATTRIBUTE_ACCESS);
+    CHECK(aapl_id, H5I_INVALID_HID, "H5Pcreate");
 
     /* Create dataset access property list */
     dapl_id = H5Pcreate(H5P_DATASET_ACCESS);
-    CHECK(dapl_id, FAIL, "H5Pcreate");
+    CHECK(dapl_id, H5I_INVALID_HID, "H5Pcreate");
 
     /* Create a group */
     group = H5Gcreate2(fid1, "Group1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(group, FAIL, "H5Gcreate2");
+    CHECK(group, H5I_INVALID_HID, "H5Gcreate2");
 
     /* Set group's comment */
     ret = H5Oset_comment(group, write_comment);
@@ -113,10 +134,7 @@ test_reference_params(void)
 
     /* Create a dataset (inside Group1) */
     dataset = H5Dcreate2(group, "Dataset1", H5T_NATIVE_UINT, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(dataset, FAIL, "H5Dcreate2");
-
-    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
-        *tu32++ = (unsigned)i * 3;
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Write selection to disk */
     ret = H5Dwrite(dataset, H5T_NATIVE_UINT, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
@@ -128,7 +146,19 @@ test_reference_params(void)
 
     /* Create another dataset (inside Group1) */
     dataset = H5Dcreate2(group, "Dataset2", H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(dataset, FAIL, "H5Dcreate2");
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    /* Create an attribute for the dataset */
+    attr = H5Acreate2(dataset, "Attr", H5T_NATIVE_UINT, sid1, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Acreate2");
+
+    /* Write attribute to disk */
+    ret = H5Awrite(attr, H5T_NATIVE_UINT, wbuf);
+    CHECK(ret, FAIL, "H5Awrite");
+
+    /* Close attribute */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
 
     /* Close Dataset */
     ret = H5Dclose(dataset);
@@ -136,7 +166,7 @@ test_reference_params(void)
 
     /* Create a datatype to refer to */
     tid1 = H5Tcreate(H5T_COMPOUND, sizeof(s1_t));
-    CHECK(tid1, FAIL, "H5Tcreate");
+    CHECK(tid1, H5I_INVALID_HID, "H5Tcreate");
 
     /* Insert fields */
     ret = H5Tinsert(tid1, "a", HOFFSET(s1_t,a), H5T_NATIVE_INT);
@@ -161,58 +191,88 @@ test_reference_params(void)
     CHECK(ret, FAIL, "H5Gclose");
 
     /* Create a dataset */
-    dataset = H5Dcreate2(fid1, "Dataset3", H5T_STD_REF_OBJ, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(ret, FAIL, "H5Dcreate2");
-
-    /* Test parameters to H5Rcreate */
-    ret = H5Rcreate(NULL, fid1, "/Group1/Dataset1", H5R_OBJECT, (hid_t)-1);
-    VERIFY(ret, FAIL, "H5Rcreate ref");
-    ret = H5Rcreate(&wbuf[0], (hid_t)-1, "/Group1/Dataset1", H5R_OBJECT, (hid_t)-1);
-    VERIFY(ret, FAIL, "H5Rcreate loc_id");
-    ret = H5Rcreate(&wbuf[0], fid1, NULL, H5R_OBJECT, (hid_t)-1);
-    VERIFY(ret, FAIL, "H5Rcreate name");
-    ret = H5Rcreate(&wbuf[0], fid1, "", H5R_OBJECT, (hid_t)-1);
-    VERIFY(ret, FAIL, "H5Rcreate null name");
-    ret = H5Rcreate(&wbuf[0], fid1, "/Group1/Dataset1", H5R_MAXTYPE, (hid_t)-1);
-    VERIFY(ret, FAIL, "H5Rcreate type");
-    ret = H5Rcreate(&wbuf[0], fid1, "/Group1/Dataset1", H5R_DATASET_REGION, (hid_t)-1);
-    VERIFY(ret, FAIL, "H5Rcreate region space");
-    ret = H5Rcreate(&wbuf[0], fid1, "/Group1/Dataset1", H5R_MAXTYPE, (hid_t)0);
-    VERIFY(ret, FAIL, "H5Rcreate space");
-
-    /* Test parameters to H5Rdereference */
-    dset2 = H5Rdereference2((hid_t)-1, H5P_DEFAULT, H5R_OBJECT, &rbuf[0]);
-    VERIFY(dset2, FAIL, "H5Rdereference2 loc_id");
-    dset2 = H5Rdereference2(dataset, (hid_t)-1, H5R_OBJECT, &rbuf[0]);
-    VERIFY(dset2, FAIL, "H5Rdereference2 oapl_id");
-    dset2 = H5Rdereference2(dataset, dapl_id, H5R_OBJECT, NULL);
-    VERIFY(dset2, FAIL, "H5Rdereference2 ref");
-    dset2 = H5Rdereference2(dataset, dapl_id, H5R_MAXTYPE, &rbuf[0]);
-    VERIFY(dset2, FAIL, "H5Rdereference2 type");
-
-    /* Test parameters to H5Rget_obj_type2 */
-    ret = H5Rget_obj_type2((hid_t)-1, H5R_OBJECT, &rbuf[0], NULL);
-    VERIFY(ret, FAIL, "H5Rget_obj_type2 loc_id");
-    ret = H5Rget_obj_type2(fid1, H5R_OBJECT, NULL, NULL);
-    VERIFY(ret, FAIL, "H5Rget_obj_type2 ref");
-    ret = H5Rget_obj_type2(fid1, H5R_MAXTYPE, &rbuf[0], NULL);
-    VERIFY(ret, FAIL, "H5Rget_obj_type2 type");
-
-    /* Test parameters to H5Rget_name */
-    name_size = H5Rget_name((hid_t)-1, H5R_DATASET_REGION, &rbuf[0], NULL, 0);
-    VERIFY(name_size, FAIL, "H5Rget_name loc_id");
-    name_size = H5Rget_name(fid1, H5R_DATASET_REGION, NULL, NULL, 0);
-    VERIFY(name_size, FAIL, "H5Rget_name ref");
-    name_size = H5Rget_name(fid1, H5R_MAXTYPE, &rbuf[0], NULL, 0);
-    VERIFY(name_size, FAIL, "H5Rget_name type");
-
-    /* Test parameters to H5Rget_region */
-    ret_id = H5Rget_region((hid_t)-1, H5R_OBJECT, &rbuf[0]);
-    VERIFY(ret_id, FAIL, "H5Rget_region loc_id");
-    ret_id = H5Rget_region(fid1, H5R_OBJECT, NULL);
-    VERIFY(ret_id, FAIL, "H5Rget_region ref");
-    ret_id = H5Rget_region(fid1, H5R_OBJECT, &rbuf[0]);
-    VERIFY(ret_id, FAIL, "H5Rget_region type");
+    dataset = H5Dcreate2(fid1, "Dataset3", H5T_STD_REF, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(ret, H5I_INVALID_HID, "H5Dcreate2");
+
+    /* Test parameters to H5Rcreate_object */
+    ret = H5Rcreate_object(fid1, "/Group1/Dataset1", NULL);
+    VERIFY(ret, FAIL, "H5Rcreate_object ref");
+    ret = H5Rcreate_object(H5I_INVALID_HID, "/Group1/Dataset1", &wbuf[0]);
+    VERIFY(ret, FAIL, "H5Rcreate_object loc_id");
+    ret = H5Rcreate_object(fid1, NULL, &wbuf[0]);
+    VERIFY(ret, FAIL, "H5Rcreate_object name");
+    ret = H5Rcreate_object(fid1, "", &wbuf[0]);
+    VERIFY(ret, FAIL, "H5Rcreate_object null name");
+
+    /* Test parameters to H5Rcreate_region */
+    ret = H5Rcreate_region(fid1, "/Group1/Dataset1", sid1, NULL);
+    VERIFY(ret, FAIL, "H5Rcreate_region ref");
+    ret = H5Rcreate_region(H5I_INVALID_HID, "/Group1/Dataset1", sid1, &wbuf[0]);
+    VERIFY(ret, FAIL, "H5Rcreate_region loc_id");
+    ret = H5Rcreate_region(fid1, NULL, sid1, &wbuf[0]);
+    VERIFY(ret, FAIL, "H5Rcreate_region name");
+    ret = H5Rcreate_region(fid1, "/Group1/Dataset1", H5I_INVALID_HID, &wbuf[0]);
+    VERIFY(ret, FAIL, "H5Rcreate_region dataspace");
+
+    /* Test parameters to H5Rcreate_attr */
+    ret = H5Rcreate_attr(fid1, "/Group1/Dataset2", "Attr", NULL);
+    VERIFY(ret, FAIL, "H5Rcreate_attr ref");
+    ret = H5Rcreate_attr(H5I_INVALID_HID, "/Group1/Dataset2", "Attr", &wbuf[0]);
+    VERIFY(ret, FAIL, "H5Rcreate_attr loc_id");
+    ret = H5Rcreate_attr(fid1, NULL, "Attr", &wbuf[0]);
+    VERIFY(ret, FAIL, "H5Rcreate_attr name");
+    ret = H5Rcreate_attr(fid1, "/Group1/Dataset2", NULL, &wbuf[0]);
+    VERIFY(ret, FAIL, "H5Rcreate_attr attr_name");
+
+    /* Test parameters to H5Rdestroy */
+    ret = H5Rdestroy(NULL);
+    VERIFY(ret, FAIL, "H5Rdestroy");
+
+    /* Test parameters to H5Rget_type */
+    type = H5Rget_type(NULL);
+    VERIFY(type, H5R_BADTYPE, "H5Rget_type ref");
+
+    /* Test parameters to H5Requal */
+    ret = H5Requal(NULL, (const H5R_ref_t *)&rbuf[0]);
+    VERIFY(ret, FAIL, "H5Requal ref1");
+    ret = H5Requal((const H5R_ref_t *)&rbuf[0], NULL);
+    VERIFY(ret, FAIL, "H5Requal ref2");
+
+    /* Test parameters to H5Rcopy */
+    ret = H5Rcopy(NULL, &wbuf[0]);
+    VERIFY(ret, FAIL, "H5Rcopy src_ref");
+    ret = H5Rcopy((const H5R_ref_t *)&rbuf[0], NULL);
+    VERIFY(ret, FAIL, "H5Rcopy dest_ref");
+
+    /* Test parameters to H5Ropen_object */
+    dset2 = H5Ropen_object((const H5R_ref_t *)&rbuf[0], H5I_INVALID_HID, H5I_INVALID_HID);
+    VERIFY(dset2, FAIL, "H5Ropen_object oapl_id");
+    dset2 = H5Ropen_object(NULL, H5P_DEFAULT, dapl_id);
+    VERIFY(dset2, FAIL, "H5Ropen_object ref");
+
+    /* Test parameters to H5Ropen_region */
+    ret_id = H5Ropen_region(NULL, H5I_INVALID_HID, H5I_INVALID_HID);
+    VERIFY(ret_id, H5I_INVALID_HID, "H5Ropen_region ref");
+
+    /* Test parameters to H5Ropen_attr */
+    ret_id = H5Ropen_attr(NULL, H5P_DEFAULT, aapl_id);
+    VERIFY(ret_id, H5I_INVALID_HID, "H5Ropen_attr ref");
+
+    /* Test parameters to H5Rget_obj_type3 */
+    ret = H5Rget_obj_type3(NULL, H5P_DEFAULT, NULL);
+    VERIFY(ret, FAIL, "H5Rget_obj_type3 ref");
+
+    /* Test parameters to H5Rget_file_name */
+    name_size = H5Rget_file_name(NULL, NULL, 0);
+    VERIFY(name_size, (-1), "H5Rget_file_name ref");
+
+    /* Test parameters to H5Rget_obj_name */
+    name_size = H5Rget_obj_name(NULL, H5P_DEFAULT, NULL, 0);
+    VERIFY(name_size, (-1), "H5Rget_obj_name ref");
+
+    /* Test parameters to H5Rget_attr_name */
+    name_size = H5Rget_attr_name(NULL, NULL, 0);
+    VERIFY(name_size, (-1), "H5Rget_attr_name ref");
 
     /* Close disk dataspace */
     ret = H5Sclose(sid1);
@@ -222,6 +282,10 @@ test_reference_params(void)
     ret = H5Pclose(dapl_id);
     CHECK(ret, FAIL, "H5Pclose");
 
+    /* Close attribute access property list */
+    ret = H5Pclose(aapl_id);
+    CHECK(ret, FAIL, "H5Pclose");
+
     /* Close Dataset */
     ret = H5Dclose(dataset);
     CHECK(ret, FAIL, "H5Dclose");
@@ -234,7 +298,7 @@ test_reference_params(void)
     HDfree(wbuf);
     HDfree(rbuf);
     HDfree(tbuf);
-}   /* test_reference_obj() */
+}   /* test_reference_params() */
 
 /****************************************************************
 **
@@ -245,60 +309,52 @@ test_reference_params(void)
 static void
 test_reference_obj(void)
 {
-    hid_t        fid1;        /* HDF5 File IDs        */
-    hid_t        dataset,    /* Dataset ID            */
-                        dset2;      /* Dereferenced dataset ID */
-    hid_t        group;      /* Group ID             */
-    hid_t        sid1;       /* Dataspace ID            */
-    hid_t        tid1;       /* Datatype ID            */
-    hsize_t        dims1[] = {SPACE1_DIM1};
-    hid_t               dapl_id;    /* Dataset access property list */
-    hobj_ref_t          *wbuf,      /* buffer to write to disk */
-                        *rbuf,      /* buffer read from disk */
-                        *tbuf;      /* temp. buffer read from disk */
-    hobj_ref_t  nvrbuf[3]={0,101,1000000000}; /* buffer with non-valid refs */
-    unsigned            *tu32;      /* Temporary pointer to uint32 data */
-    int                 i, j;       /* counting variables */
-    const char *write_comment="Foo!"; /* Comments for group */
-    char read_comment[10];
-    H5O_type_t          obj_type;   /* Object type */
-    ssize_t             size;       /* Comment length */
-    herr_t        ret;        /* Generic return value        */
+    hid_t       fid1;       /* HDF5 File IDs                    */
+    hid_t       dataset,    /* Dataset ID                       */
+                dset2;      /* Dereferenced dataset ID          */
+    hid_t       group;      /* Group ID                         */
+    hid_t       sid1;       /* Dataspace ID                     */
+    hid_t       tid1;       /* Datatype ID                      */
+    hsize_t     dims1[] = {SPACE1_DIM1};
+    hid_t       dapl_id;    /* Dataset access property list     */
+    H5R_ref_t     *wbuf,       /* buffer to write to disk          */
+               *rbuf,       /* buffer read from disk            */
+               *tbuf;       /* temp. buffer read from disk      */
+    unsigned   *tu32;       /* Temporary pointer to uint32 data */
+    int         i, j;       /* Counters                         */
+    H5O_type_t  obj_type;   /* Object type                      */
+    herr_t      ret;        /* Generic return value             */
 
     /* Output message about test being performed */
     MESSAGE(5, ("Testing Object Reference Functions\n"));
 
     /* Allocate write & read buffers */
-    wbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
-    rbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
-    tbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
+    wbuf = (H5R_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(H5R_ref_t)), SPACE1_DIM1);
+    rbuf = (H5R_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(H5R_ref_t)), SPACE1_DIM1);
+    tbuf = (H5R_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(H5R_ref_t)), SPACE1_DIM1);
+
+    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
+        *tu32++ = (unsigned)i * 3;
 
     /* Create file */
-    fid1 = H5Fcreate(FILE1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(fid1, FAIL, "H5Fcreate");
+    fid1 = H5Fcreate(FILE_REF_OBJ, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fcreate");
 
     /* Create dataspace for datasets */
     sid1 = H5Screate_simple(SPACE1_RANK, dims1, NULL);
-    CHECK(sid1, FAIL, "H5Screate_simple");
+    CHECK(sid1, H5I_INVALID_HID, "H5Screate_simple");
 
     /* Create dataset access property list */
     dapl_id = H5Pcreate(H5P_DATASET_ACCESS);
-    CHECK(dapl_id, FAIL, "H5Pcreate");
+    CHECK(dapl_id, H5I_INVALID_HID, "H5Pcreate");
 
     /* Create a group */
     group = H5Gcreate2(fid1, "Group1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(group, FAIL, "H5Gcreate2");
-
-    /* Set group's comment */
-    ret = H5Oset_comment(group, write_comment);
-    CHECK(ret, FAIL, "H5Oset_comment");
+    CHECK(group, H5I_INVALID_HID, "H5Gcreate2");
 
     /* Create a dataset (inside Group1) */
     dataset = H5Dcreate2(group, "Dataset1", H5T_NATIVE_UINT, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(dataset, FAIL, "H5Dcreate2");
-
-    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
-        *tu32++ = (unsigned)i * 3;
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Write selection to disk */
     ret = H5Dwrite(dataset, H5T_NATIVE_UINT, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
@@ -318,7 +374,7 @@ test_reference_obj(void)
 
     /* Create a datatype to refer to */
     tid1 = H5Tcreate(H5T_COMPOUND, sizeof(s1_t));
-    CHECK(tid1, FAIL, "H5Tcreate");
+    CHECK(tid1, H5I_INVALID_HID, "H5Tcreate");
 
     /* Insert fields */
     ret = H5Tinsert(tid1, "a", HOFFSET(s1_t,a), H5T_NATIVE_INT);
@@ -343,39 +399,39 @@ test_reference_obj(void)
     CHECK(ret, FAIL, "H5Gclose");
 
     /* Create a dataset */
-    dataset = H5Dcreate2(fid1, "Dataset3", H5T_STD_REF_OBJ, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(ret, FAIL, "H5Dcreate2");
+    dataset = H5Dcreate2(fid1, "Dataset3", H5T_STD_REF, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Create reference to dataset */
-    ret = H5Rcreate(&wbuf[0], fid1, "/Group1/Dataset1", H5R_OBJECT, (hid_t)-1);
-    CHECK(ret, FAIL, "H5Rcreate");
-    ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &wbuf[0], &obj_type);
-    CHECK(ret, FAIL, "H5Rget_obj_type2");
-    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+    ret = H5Rcreate_object(fid1, "/Group1/Dataset1", &wbuf[0]);
+    CHECK(ret, FAIL, "H5Rcreate_object");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&wbuf[0], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
 
     /* Create reference to dataset */
-    ret = H5Rcreate(&wbuf[1], fid1, "/Group1/Dataset2", H5R_OBJECT, (hid_t)-1);
-    CHECK(ret, FAIL, "H5Rcreate");
-    ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &wbuf[1], &obj_type);
-    CHECK(ret, FAIL, "H5Rget_obj_type2");
-    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+    ret = H5Rcreate_object(fid1, "/Group1/Dataset2", &wbuf[1]);
+    CHECK(ret, FAIL, "H5Rcreate_object");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&wbuf[1], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
 
     /* Create reference to group */
-    ret = H5Rcreate(&wbuf[2], fid1, "/Group1", H5R_OBJECT, (hid_t)-1);
-    CHECK(ret, FAIL, "H5Rcreate");
-    ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &wbuf[2], &obj_type);
-    CHECK(ret, FAIL, "H5Rget_obj_type2");
-    VERIFY(obj_type, H5O_TYPE_GROUP, "H5Rget_obj_type2");
+    ret = H5Rcreate_object(fid1, "/Group1", &wbuf[2]);
+    CHECK(ret, FAIL, "H5Rcreate_object");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&wbuf[2], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_GROUP, "H5Rget_obj_type3");
 
     /* Create reference to named datatype */
-    ret = H5Rcreate(&wbuf[3], fid1, "/Group1/Datatype1", H5R_OBJECT, (hid_t)-1);
-    CHECK(ret, FAIL, "H5Rcreate");
-    ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &wbuf[3], &obj_type);
-    CHECK(ret, FAIL, "H5Rget_obj_type2");
-    VERIFY(obj_type, H5O_TYPE_NAMED_DATATYPE, "H5Rget_obj_type2");
+    ret = H5Rcreate_object(fid1, "/Group1/Datatype1", &wbuf[3]);
+    CHECK(ret, FAIL, "H5Rcreate_object");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&wbuf[3], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_NAMED_DATATYPE, "H5Rget_obj_type3");
 
     /* Write selection to disk */
-    ret = H5Dwrite(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
+    ret = H5Dwrite(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
     CHECK(ret, FAIL, "H5Dwrite");
 
     /* Close disk dataspace */
@@ -391,27 +447,27 @@ test_reference_obj(void)
     CHECK(ret, FAIL, "H5Fclose");
 
     /* Re-open the file */
-    fid1 = H5Fopen(FILE1, H5F_ACC_RDWR, H5P_DEFAULT);
-    CHECK(fid1, FAIL, "H5Fopen");
+    fid1 = H5Fopen(FILE_REF_OBJ, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fopen");
 
     /* Open the dataset */
     dataset = H5Dopen2(fid1, "/Dataset3", H5P_DEFAULT);
-    CHECK(ret, FAIL, "H5Dopen2");
+    CHECK(dataset, H5I_INVALID_HID, "H5Dopen2");
 
     /* Read selection from disk */
-    ret = H5Dread(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf);
+    ret = H5Dread(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf);
     CHECK(ret, FAIL, "H5Dread");
 
     /* Open dataset object */
-    dset2 = H5Rdereference2(dataset, dapl_id, H5R_OBJECT, &rbuf[0]);
-    CHECK(dset2, FAIL, "H5Rdereference2");
+    dset2 = H5Ropen_object((const H5R_ref_t *)&rbuf[0], H5P_DEFAULT, dapl_id);
+    CHECK(dset2, H5I_INVALID_HID, "H5Ropen_object");
 
     /* Check information in referenced dataset */
     sid1 = H5Dget_space(dset2);
-    CHECK(sid1, FAIL, "H5Dget_space");
+    CHECK(sid1, H5I_INVALID_HID, "H5Dget_space");
 
     ret = (int)H5Sget_simple_extent_npoints(sid1);
-    VERIFY(ret, 4, "H5Sget_simple_extent_npoints");
+    VERIFY(ret, SPACE1_DIM1, "H5Sget_simple_extent_npoints");
 
     /* Read from disk */
     ret = H5Dread(dset2, H5T_NATIVE_UINT, H5S_ALL, H5S_ALL, H5P_DEFAULT, tbuf);
@@ -425,24 +481,16 @@ test_reference_obj(void)
     CHECK(ret, FAIL, "H5Dclose");
 
     /* Open group object.  GAPL isn't supported yet.  But it's harmless to pass in */
-    group = H5Rdereference2(dataset, H5P_DEFAULT, H5R_OBJECT, &rbuf[2]);
-    CHECK(group, FAIL, "H5Rdereference2");
-
-    /* Get group's comment */
-    size = H5Oget_comment(group, read_comment, (size_t)10);
-    CHECK(size, FAIL, "H5Oget_comment");
-
-    /* Check for correct comment value */
-    if(HDstrcmp(write_comment, read_comment) != 0)
-        TestErrPrintf("Error! Incorrect group comment, wanted: %s, got: %s\n",write_comment,read_comment);
+    group = H5Ropen_object((const H5R_ref_t *)&rbuf[2], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(group, H5I_INVALID_HID, "H5Ropen_object");
 
     /* Close group */
     ret = H5Gclose(group);
     CHECK(ret, FAIL, "H5Gclose");
 
     /* Open datatype object. TAPL isn't supported yet.  But it's harmless to pass in */
-    tid1 = H5Rdereference2(dataset, H5P_DEFAULT, H5R_OBJECT, &rbuf[3]);
-    CHECK(tid1, FAIL, "H5Rdereference2");
+    tid1 = H5Ropen_object((const H5R_ref_t *)&rbuf[3], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(tid1, H5I_INVALID_HID, "H5Ropen_object");
 
     /* Verify correct datatype */
     {
@@ -455,14 +503,6 @@ test_reference_obj(void)
         VERIFY(ret, 3, "H5Tget_nmembers");
     }
 
-    /* Attempting to retrieve type of object using non-valid refs */
-    for(j = 0; j < 3; j++) {
-        H5E_BEGIN_TRY {
-            ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &nvrbuf[j], &obj_type);
-        } H5E_END_TRY;
-        VERIFY(ret, FAIL, "H5Rget_obj_type2");
-    } /* end for */
-
     /* Close datatype */
     ret = H5Tclose(tid1);
     CHECK(ret, FAIL, "H5Tclose");
@@ -479,6 +519,14 @@ test_reference_obj(void)
     ret = H5Fclose(fid1);
     CHECK(ret, FAIL, "H5Fclose");
 
+    /* Destroy references */
+    for(j = 0; j < SPACE1_DIM1; j++) {
+        ret = H5Rdestroy(&wbuf[j]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+        ret = H5Rdestroy(&rbuf[j]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+    }
+
     /* Free memory buffers */
     HDfree(wbuf);
     HDfree(rbuf);
@@ -498,13 +546,13 @@ test_reference_obj(void)
 static void
 test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
 {
-    hid_t fid1;         /* HDF5 File IDs */
-    hid_t fapl = -1;    /* File access property list */
-    hid_t dset1,        /* Dataset ID */
-          dset2;        /* Dereferenced dataset ID */
-    hid_t sid1,         /* Dataspace ID #1 */
-          sid2;         /* Dataspace ID #2 */
-    hid_t dapl_id;      /* Dataset access property list */
+    hid_t fid1;                     /* HDF5 File IDs */
+    hid_t fapl;                     /* File access property list */
+    hid_t dset1,                    /* Dataset ID */
+          dset2;                    /* Dereferenced dataset ID */
+    hid_t sid1,                     /* Dataspace ID #1 */
+          sid2;                     /* Dataspace ID #2 */
+    hid_t dapl_id;                  /* Dataset access property list */
     hsize_t dims1[] = {SPACE1_DIM1},
             dims2[] = {SPACE2_DIM1, SPACE2_DIM2};
     hsize_t start[SPACE2_RANK];     /* Starting location of hyperslab */
@@ -512,62 +560,60 @@ test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
     hsize_t count[SPACE2_RANK];     /* Element count of hyperslab */
     hsize_t block[SPACE2_RANK];     /* Block size of hyperslab */
     hsize_t coord1[POINT1_NPOINTS][SPACE2_RANK]; /* Coordinates for point selection */
-    hsize_t *coords;            /* Coordinate buffer */
-    hsize_t low[SPACE2_RANK];   /* Selection bounds */
-    hsize_t high[SPACE2_RANK];  /* Selection bounds */
-    hdset_reg_ref_t *wbuf,      /* buffer to write to disk */
-                    *rbuf;      /* buffer read from disk */
-    hdset_reg_ref_t  nvrbuf[3]={{0},{101},{255}}; /* buffer with non-valid refs */
-    uint8_t *dwbuf,             /* Buffer for writing numeric data to disk */
-            *drbuf;             /* Buffer for reading numeric data from disk */
-    uint8_t *tu8;               /* Temporary pointer to uint8 data */
-    H5O_type_t obj_type;        /* Type of object */
-    int i, j;                   /* counting variables */
-    hssize_t hssize_ret;        /* hssize_t return value */
-    htri_t tri_ret;             /* htri_t return value */
-    herr_t ret;                 /* Generic return value     */
-    hdset_reg_ref_t undef_reg[1];   /* test for undefined reference */
-    hid_t dset_NA;              /* Dataset id for undefined reference */
-    hid_t space_NA;             /* Dataspace id for undefined reference */
-    hsize_t dims_NA[1] = {1};   /* Dims array for undefined reference */
-    hdset_reg_ref_t wdata_NA[1],    /* Write buffer */
-                    rdata_NA[1];    /* Read buffer */
+    hsize_t *coords;                /* Coordinate buffer */
+    hsize_t low[SPACE2_RANK];       /* Selection bounds */
+    hsize_t high[SPACE2_RANK];      /* Selection bounds */
+    H5R_ref_t *wbuf,                   /* buffer to write to disk */
+           *rbuf;                   /* buffer read from disk */
+    H5R_ref_t  nvrbuf[3]={{0},{101},{255}}; /* buffer with non-valid refs */
+    uint8_t *dwbuf,                 /* Buffer for writing numeric data to disk */
+            *drbuf;                 /* Buffer for reading numeric data from disk */
+    uint8_t *tu8;                   /* Temporary pointer to uint8 data */
+    H5O_type_t obj_type;            /* Type of object */
+    int i, j;                       /* Counters */
+    hssize_t hssize_ret;            /* hssize_t return value */
+    htri_t tri_ret;                 /* htri_t return value */
+    herr_t ret;                     /* Generic return value     */
+    hid_t dset_NA;                  /* Dataset id for undefined reference */
+    hid_t space_NA;                 /* Dataspace id for undefined reference */
+    hsize_t dims_NA[1] = {1};       /* Dims array for undefined reference */
+    H5R_ref_t rdata_NA[1];             /* Read buffer */
 
     /* Output message about test being performed */
     MESSAGE(5, ("Testing Dataset Region Reference Functions\n"));
 
     /* Allocate write & read buffers */
-    wbuf = (hdset_reg_ref_t *)HDcalloc(sizeof(hdset_reg_ref_t), (size_t)SPACE1_DIM1);
-    rbuf = (hdset_reg_ref_t *)HDmalloc(sizeof(hdset_reg_ref_t) * SPACE1_DIM1);
-    dwbuf = (uint8_t *)HDmalloc(sizeof(uint8_t) * SPACE2_DIM1 * SPACE2_DIM2);
+    wbuf = (H5R_ref_t *)HDcalloc(sizeof(H5R_ref_t), SPACE1_DIM1);
+    rbuf = (H5R_ref_t *)HDcalloc(sizeof(H5R_ref_t), SPACE1_DIM1);
+    dwbuf = (uint8_t *)HDcalloc(sizeof(uint8_t), (size_t)(SPACE2_DIM1 * SPACE2_DIM2));
     drbuf = (uint8_t *)HDcalloc(sizeof(uint8_t), (size_t)(SPACE2_DIM1 * SPACE2_DIM2));
 
+    for(tu8 = dwbuf, i = 0; i < (SPACE2_DIM1 * SPACE2_DIM2); i++)
+        *tu8++ = (uint8_t)(i * 3);
+
     /* Create file access property list */
     fapl = H5Pcreate(H5P_FILE_ACCESS);
-    CHECK(fapl, FAIL, "H5Pcreate");
+    CHECK(fapl, H5I_INVALID_HID, "H5Pcreate");
 
     /* Set the low/high version bounds in fapl */
     ret = H5Pset_libver_bounds(fapl, libver_low, libver_high);
     CHECK(ret, FAIL, "H5Pset_libver_bounds");
 
     /* Create file with the fapl */
-    fid1 = H5Fcreate(FILE2, H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
-    CHECK(fid1, FAIL, "H5Fcreate");
+    fid1 = H5Fcreate(FILE_REF_REG, H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fcreate");
 
     /* Create dataspace for datasets */
     sid2 = H5Screate_simple(SPACE2_RANK, dims2, NULL);
-    CHECK(sid2, FAIL, "H5Screate_simple");
+    CHECK(sid2, H5I_INVALID_HID, "H5Screate_simple");
 
     /* Create dataset access property list */
     dapl_id = H5Pcreate(H5P_DATASET_ACCESS);
-    CHECK(dapl_id, FAIL, "H5Pcreate");
+    CHECK(dapl_id, H5I_INVALID_HID, "H5Pcreate");
 
     /* Create a dataset */
     dset2 = H5Dcreate2(fid1, "Dataset2", H5T_STD_U8LE, sid2, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(dset2, FAIL, "H5Dcreate2");
-
-    for(tu8 = dwbuf, i = 0; i < (SPACE2_DIM1 * SPACE2_DIM2); i++)
-        *tu8++ = (uint8_t)(i * 3);
+    CHECK(dset2, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Write selection to disk */
     ret = H5Dwrite(dset2, H5T_STD_U8LE, H5S_ALL, H5S_ALL, H5P_DEFAULT, dwbuf);
@@ -579,11 +625,11 @@ test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
 
     /* Create dataspace for the reference dataset */
     sid1 = H5Screate_simple(SPACE1_RANK, dims1, NULL);
-    CHECK(sid1, FAIL, "H5Screate_simple");
+    CHECK(sid1, H5I_INVALID_HID, "H5Screate_simple");
 
     /* Create a dataset */
-    dset1 = H5Dcreate2(fid1, "Dataset1", H5T_STD_REF_DSETREG, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(ret, FAIL, "H5Dcreate2");
+    dset1 = H5Dcreate2(fid1, "Dataset1", H5T_STD_REF, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dset1, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Create references */
 
@@ -599,11 +645,11 @@ test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
     VERIFY(ret, 36, "H5Sget_select_npoints");
 
     /* Store first dataset region */
-    ret = H5Rcreate(&wbuf[0], fid1, "/Dataset2", H5R_DATASET_REGION, sid2);
-    CHECK(ret, FAIL, "H5Rcreate");
-    ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &wbuf[0], &obj_type);
-    CHECK(ret, FAIL, "H5Rget_obj_type2");
-    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+    ret = H5Rcreate_region(fid1, "/Dataset2", sid2, &wbuf[0]);
+    CHECK(ret, FAIL, "H5Rcreate_region");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&wbuf[0], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
 
     /* Select sequence of ten points for second reference */
     coord1[0][0] = 6; coord1[0][1] = 9;
@@ -620,17 +666,21 @@ test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
     CHECK(ret, FAIL, "H5Sselect_elements");
 
     ret = (int)H5Sget_select_npoints(sid2);
-    VERIFY(ret, 10, "H5Sget_select_npoints");
+    VERIFY(ret, SPACE2_DIM2, "H5Sget_select_npoints");
 
     /* Store second dataset region */
-    ret = H5Rcreate(&wbuf[1], fid1, "/Dataset2", H5R_DATASET_REGION, sid2);
-    CHECK(ret, FAIL, "H5Rcreate");
+    ret = H5Rcreate_region(fid1, "/Dataset2", sid2, &wbuf[1]);
+    CHECK(ret, FAIL, "H5Rcreate_region");
 
     /* Select unlimited hyperslab for third reference */
-    start[0] = 1; start[1] = 8;
-    stride[0] = 4; stride[1] = 1;
-    count[0] = H5S_UNLIMITED; count[1] = 1;
-    block[0] = 2; block[1] = 2;
+    start[0] = 1;
+    start[1] = 8;
+    stride[0] = 4;
+    stride[1] = 1;
+    count[0] = H5S_UNLIMITED;
+    count[1] = 1;
+    block[0] = 2;
+    block[1] = 2;
     ret = H5Sselect_hyperslab(sid2, H5S_SELECT_SET, start, stride, count, block);
     CHECK(ret, FAIL, "H5Sselect_hyperslab");
 
@@ -638,41 +688,39 @@ test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
     VERIFY(hssize_ret, (hssize_t)H5S_UNLIMITED, "H5Sget_select_npoints");
 
     /* Store third dataset region */
+    ret = H5Rcreate_region(fid1, "/Dataset2", sid2, &wbuf[2]);
+    CHECK(ret, FAIL, "H5Rcreate_region");
+
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&wbuf[2], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
+
+    /* Store fourth dataset region */
+    ret = H5Rcreate_region(fid1, "/Dataset2", sid2, &wbuf[3]);
+    CHECK(ret, FAIL, "H5Rcreate_region");
+
+    /* Write selection to disk */
     H5E_BEGIN_TRY {
-        ret = H5Rcreate(&wbuf[2], fid1, "/Dataset2", H5R_DATASET_REGION, sid2);
+        ret = H5Dwrite(dset1, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
     } H5E_END_TRY;
 
     if(libver_high < H5F_LIBVER_V110)
-        VERIFY(ret, FAIL, "H5Rcreate");
+        VERIFY(ret, FAIL, "H5Dwrite");
     else
-        CHECK(ret, FAIL, "H5Rcreate");
-
-    ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &wbuf[0], &obj_type);
-    CHECK(ret, FAIL, "H5Rget_obj_type2");
-    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
-
-    /* Write selection to disk */
-    ret = H5Dwrite(dset1, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
-    CHECK(ret, FAIL, "H5Dwrite");
+        CHECK(ret, FAIL, "H5Dwrite");
 
     /*
      * Store a dataset region reference which will not get written to disk
      */
 
-    /* Create reference to an element in dset1 */
-    ret = H5Sselect_elements(sid2, H5S_SELECT_SET, (size_t)1, (const hsize_t *)coord1);
-    CHECK(ret, FAIL, "H5Sselect_elements");
-    ret = H5Rcreate(&wdata_NA[0], fid1, "/Dataset1", H5R_DATASET_REGION, sid2);
-    CHECK(ret, FAIL, "H5Rcreate");
-
     /* Create the dataspace of the region references */
     space_NA = H5Screate_simple(1, dims_NA, NULL);
-    CHECK(space_NA, FAIL, "H5Screate_simple");
+    CHECK(space_NA, H5I_INVALID_HID, "H5Screate_simple");
 
     /* Create the dataset and write the region references to it */
-    dset_NA = H5Dcreate2(fid1, "DS_NA", H5T_STD_REF_DSETREG, space_NA, H5P_DEFAULT,
+    dset_NA = H5Dcreate2(fid1, "DS_NA", H5T_STD_REF, space_NA, H5P_DEFAULT,
                 H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(dset_NA, FAIL, "H5Dcreate");
+    CHECK(dset_NA, H5I_INVALID_HID, "H5Dcreate");
 
     /* Close and release resources for undefined region reference tests */
     ret = H5Dclose(dset_NA);
@@ -697,8 +745,8 @@ test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
     CHECK(ret, FAIL, "H5Fclose");
 
     /* Re-open the file */
-    fid1 = H5Fopen(FILE2, H5F_ACC_RDWR, fapl);
-    CHECK(fid1, FAIL, "H5Fopen");
+    fid1 = H5Fopen(FILE_REF_REG, H5F_ACC_RDWR, fapl);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fopen");
 
     /*
      * Start the test of an undefined reference
@@ -706,25 +754,25 @@ test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
 
     /* Open the dataset of the undefined references */
     dset_NA = H5Dopen2(fid1, "DS_NA", H5P_DEFAULT);
-    CHECK(dset_NA, FAIL, "H5Dopen2");
+    CHECK(dset_NA, H5I_INVALID_HID, "H5Dopen2");
 
     /* Read the data */
-    ret = H5Dread(dset_NA, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, rdata_NA);
+    ret = H5Dread(dset_NA, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, rdata_NA);
     CHECK(ret, FAIL, "H5Dread");
 
     /*
      * Dereference an undefined reference (should fail)
      */
     H5E_BEGIN_TRY {
-      dset2 = H5Rdereference2(dset_NA, H5P_DEFAULT, H5R_DATASET_REGION, &rdata_NA[0]);
+      dset2 = H5Ropen_object((const H5R_ref_t *)&rdata_NA[0], H5P_DEFAULT, H5P_DEFAULT);
     } H5E_END_TRY;
-    VERIFY(dset2, FAIL, "H5Rdereference2");
+    VERIFY(dset2, H5I_INVALID_HID, "H5Ropen_object");
 
     /* Close and release resources. */
     ret = H5Dclose(dset_NA);
     CHECK(ret, FAIL, "H5Dclose");
 
-    /* This close should fail since H5Rdereference2 never created
+    /* This close should fail since H5Ropen_object never created
      * the id of the referenced object. */
     H5E_BEGIN_TRY {
       ret = H5Dclose(dset2);
@@ -737,115 +785,116 @@ test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
 
     /* Open the dataset */
     dset1 = H5Dopen2(fid1, "/Dataset1", H5P_DEFAULT);
-    CHECK(dset1, FAIL, "H5Dopen2");
+    CHECK(dset1, H5I_INVALID_HID, "H5Dopen2");
 
     /* Read selection from disk */
-    ret = H5Dread(dset1, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf);
-    CHECK(ret, FAIL, "H5Dread");
-
-    /* Try to read an unaddressed dataset */
-    dset2 = H5Rdereference2(dset1, dapl_id, H5R_DATASET_REGION, undef_reg);
-    VERIFY(dset2, FAIL, "H5Rdereference2 haddr_undef");
+    H5E_BEGIN_TRY {
+        ret = H5Dread(dset1, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf);
+    } H5E_END_TRY;
 
-    /* Try to open objects */
-    dset2 = H5Rdereference2(dset1, dapl_id, H5R_DATASET_REGION, &rbuf[0]);
-    CHECK(dset2, FAIL, "H5Rdereference2");
+    if(libver_high < H5F_LIBVER_V110)
+        VERIFY(ret, FAIL, "H5Dread");
+    else {
+        CHECK(ret, FAIL, "H5Dread");
 
-    /* Check what H5Rget_obj_type2 function returns */
-    ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &rbuf[0], &obj_type);
-    CHECK(ret, FAIL, "H5Rget_obj_type2");
-    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+        /* Try to open objects */
+        dset2 = H5Ropen_object((const H5R_ref_t *)&rbuf[0], H5P_DEFAULT, dapl_id);
+        CHECK(dset2, H5I_INVALID_HID, "H5Ropen_object");
 
-    /* Check information in referenced dataset */
-    sid1 = H5Dget_space(dset2);
-    CHECK(sid1, FAIL, "H5Dget_space");
+        /* Check what H5Rget_obj_type3 function returns */
+        ret = H5Rget_obj_type3((const H5R_ref_t *)&rbuf[0], H5P_DEFAULT, &obj_type);
+        CHECK(ret, FAIL, "H5Rget_obj_type3");
+        VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
 
-    ret = (int)H5Sget_simple_extent_npoints(sid1);
-    VERIFY(ret, 100, "H5Sget_simple_extent_npoints");
+        /* Check information in referenced dataset */
+        sid1 = H5Dget_space(dset2);
+        CHECK(sid1, H5I_INVALID_HID, "H5Dget_space");
 
-    /* Read from disk */
-    ret = H5Dread(dset2, H5T_STD_U8LE, H5S_ALL, H5S_ALL, H5P_DEFAULT, drbuf);
-    CHECK(ret, FAIL, "H5Dread");
+        ret = (int)H5Sget_simple_extent_npoints(sid1);
+        VERIFY(ret, (SPACE2_DIM1 * SPACE2_DIM2), "H5Sget_simple_extent_npoints");
 
-    for(tu8 = (uint8_t *)drbuf, i = 0; i < (SPACE2_DIM1 * SPACE2_DIM2); i++, tu8++)
-        VERIFY(*tu8, (uint8_t)(i * 3), "Data");
+        /* Read from disk */
+        ret = H5Dread(dset2, H5T_STD_U8LE, H5S_ALL, H5S_ALL, H5P_DEFAULT, drbuf);
+        CHECK(ret, FAIL, "H5Dread");
 
-    /* Get the hyperslab selection */
-    sid2 = H5Rget_region(dset1, H5R_DATASET_REGION, &rbuf[0]);
-    CHECK(sid2, FAIL, "H5Rget_region");
+        for(tu8 = (uint8_t *)drbuf, i = 0; i < (SPACE2_DIM1 * SPACE2_DIM2); i++, tu8++)
+            VERIFY(*tu8, (uint8_t)(i * 3), "Data");
 
-    /* Verify correct hyperslab selected */
-    ret = (int)H5Sget_select_npoints(sid2);
-    VERIFY(ret, 36, "H5Sget_select_npoints");
-    ret = (int)H5Sget_select_hyper_nblocks(sid2);
-    VERIFY(ret, 1, "H5Sget_select_hyper_nblocks");
-    coords = (hsize_t *)HDmalloc((size_t)ret * SPACE2_RANK * sizeof(hsize_t) * 2); /* allocate space for the hyperslab blocks */
-    ret = H5Sget_select_hyper_blocklist(sid2, (hsize_t)0, (hsize_t)ret, coords);
-    CHECK(ret, FAIL, "H5Sget_select_hyper_blocklist");
-    VERIFY(coords[0], 2, "Hyperslab Coordinates");
-    VERIFY(coords[1], 2, "Hyperslab Coordinates");
-    VERIFY(coords[2], 7, "Hyperslab Coordinates");
-    VERIFY(coords[3], 7, "Hyperslab Coordinates");
-    HDfree(coords);
-    ret = H5Sget_select_bounds(sid2, low, high);
-    CHECK(ret, FAIL, "H5Sget_select_bounds");
-    VERIFY(low[0], 2, "Selection Bounds");
-    VERIFY(low[1], 2, "Selection Bounds");
-    VERIFY(high[0], 7, "Selection Bounds");
-    VERIFY(high[1], 7, "Selection Bounds");
+        /* Get the hyperslab selection */
+        sid2 = H5Ropen_region((const H5R_ref_t *)&rbuf[0], H5P_DEFAULT, H5P_DEFAULT);
+        CHECK(sid2, H5I_INVALID_HID, "H5Ropen_region");
 
-    /* Close region space */
-    ret = H5Sclose(sid2);
-    CHECK(ret, FAIL, "H5Sclose");
+        /* Verify correct hyperslab selected */
+        ret = (int)H5Sget_select_npoints(sid2);
+        VERIFY(ret, 36, "H5Sget_select_npoints");
+        ret = (int)H5Sget_select_hyper_nblocks(sid2);
+        VERIFY(ret, 1, "H5Sget_select_hyper_nblocks");
+        coords = (hsize_t *)HDmalloc((size_t)ret * SPACE2_RANK * sizeof(hsize_t) * 2); /* allocate space for the hyperslab blocks */
+        ret = H5Sget_select_hyper_blocklist(sid2, (hsize_t)0, (hsize_t)ret, coords);
+        CHECK(ret, FAIL, "H5Sget_select_hyper_blocklist");
+        VERIFY(coords[0], 2, "Hyperslab Coordinates");
+        VERIFY(coords[1], 2, "Hyperslab Coordinates");
+        VERIFY(coords[2], 7, "Hyperslab Coordinates");
+        VERIFY(coords[3], 7, "Hyperslab Coordinates");
+        HDfree(coords);
+        ret = H5Sget_select_bounds(sid2, low, high);
+        CHECK(ret, FAIL, "H5Sget_select_bounds");
+        VERIFY(low[0], 2, "Selection Bounds");
+        VERIFY(low[1], 2, "Selection Bounds");
+        VERIFY(high[0], 7, "Selection Bounds");
+        VERIFY(high[1], 7, "Selection Bounds");
 
-    /* Get the element selection */
-    sid2 = H5Rget_region(dset1, H5R_DATASET_REGION, &rbuf[1]);
-    CHECK(sid2, FAIL, "H5Rget_region");
+        /* Close region space */
+        ret = H5Sclose(sid2);
+        CHECK(ret, FAIL, "H5Sclose");
 
-    /* Verify correct elements selected */
-    ret = (int)H5Sget_select_npoints(sid2);
-    VERIFY(ret, 10, "H5Sget_select_npoints");
-    ret = (int)H5Sget_select_elem_npoints(sid2);
-    VERIFY(ret, 10, "H5Sget_select_elem_npoints");
-    coords = (hsize_t *)HDmalloc((size_t)ret * SPACE2_RANK * sizeof(hsize_t)); /* allocate space for the element points */
-    ret = H5Sget_select_elem_pointlist(sid2, (hsize_t)0, (hsize_t)ret, coords);
-    CHECK(ret, FAIL, "H5Sget_select_elem_pointlist");
-    VERIFY(coords[0], coord1[0][0], "Element Coordinates");
-    VERIFY(coords[1], coord1[0][1], "Element Coordinates");
-    VERIFY(coords[2], coord1[1][0], "Element Coordinates");
-    VERIFY(coords[3], coord1[1][1], "Element Coordinates");
-    VERIFY(coords[4], coord1[2][0], "Element Coordinates");
-    VERIFY(coords[5], coord1[2][1], "Element Coordinates");
-    VERIFY(coords[6], coord1[3][0], "Element Coordinates");
-    VERIFY(coords[7], coord1[3][1], "Element Coordinates");
-    VERIFY(coords[8], coord1[4][0], "Element Coordinates");
-    VERIFY(coords[9], coord1[4][1], "Element Coordinates");
-    VERIFY(coords[10], coord1[5][0], "Element Coordinates");
-    VERIFY(coords[11], coord1[5][1], "Element Coordinates");
-    VERIFY(coords[12], coord1[6][0], "Element Coordinates");
-    VERIFY(coords[13], coord1[6][1], "Element Coordinates");
-    VERIFY(coords[14], coord1[7][0], "Element Coordinates");
-    VERIFY(coords[15], coord1[7][1], "Element Coordinates");
-    VERIFY(coords[16], coord1[8][0], "Element Coordinates");
-    VERIFY(coords[17], coord1[8][1], "Element Coordinates");
-    VERIFY(coords[18], coord1[9][0], "Element Coordinates");
-    VERIFY(coords[19], coord1[9][1], "Element Coordinates");
-    HDfree(coords);
-    ret = H5Sget_select_bounds(sid2, low, high);
-    CHECK(ret, FAIL, "H5Sget_select_bounds");
-    VERIFY(low[0], 0, "Selection Bounds");
-    VERIFY(low[1], 0, "Selection Bounds");
-    VERIFY(high[0], 9, "Selection Bounds");
-    VERIFY(high[1], 9, "Selection Bounds");
+        /* Get the element selection */
+        sid2 = H5Ropen_region((const H5R_ref_t *)&rbuf[1], H5P_DEFAULT, H5P_DEFAULT);
+        CHECK(sid2, H5I_INVALID_HID, "H5Ropen_region");
+
+        /* Verify correct elements selected */
+        ret = (int)H5Sget_select_npoints(sid2);
+        VERIFY(ret, SPACE2_DIM2, "H5Sget_select_npoints");
+        ret = (int)H5Sget_select_elem_npoints(sid2);
+        VERIFY(ret, SPACE2_DIM2, "H5Sget_select_elem_npoints");
+        coords = (hsize_t *)HDmalloc((size_t)ret * SPACE2_RANK * sizeof(hsize_t)); /* allocate space for the element points */
+        ret = H5Sget_select_elem_pointlist(sid2, (hsize_t)0, (hsize_t)ret, coords);
+        CHECK(ret, FAIL, "H5Sget_select_elem_pointlist");
+        VERIFY(coords[0], coord1[0][0], "Element Coordinates");
+        VERIFY(coords[1], coord1[0][1], "Element Coordinates");
+        VERIFY(coords[2], coord1[1][0], "Element Coordinates");
+        VERIFY(coords[3], coord1[1][1], "Element Coordinates");
+        VERIFY(coords[4], coord1[2][0], "Element Coordinates");
+        VERIFY(coords[5], coord1[2][1], "Element Coordinates");
+        VERIFY(coords[6], coord1[3][0], "Element Coordinates");
+        VERIFY(coords[7], coord1[3][1], "Element Coordinates");
+        VERIFY(coords[8], coord1[4][0], "Element Coordinates");
+        VERIFY(coords[9], coord1[4][1], "Element Coordinates");
+        VERIFY(coords[10], coord1[5][0], "Element Coordinates");
+        VERIFY(coords[11], coord1[5][1], "Element Coordinates");
+        VERIFY(coords[12], coord1[6][0], "Element Coordinates");
+        VERIFY(coords[13], coord1[6][1], "Element Coordinates");
+        VERIFY(coords[14], coord1[7][0], "Element Coordinates");
+        VERIFY(coords[15], coord1[7][1], "Element Coordinates");
+        VERIFY(coords[16], coord1[8][0], "Element Coordinates");
+        VERIFY(coords[17], coord1[8][1], "Element Coordinates");
+        VERIFY(coords[18], coord1[9][0], "Element Coordinates");
+        VERIFY(coords[19], coord1[9][1], "Element Coordinates");
+        HDfree(coords);
+        ret = H5Sget_select_bounds(sid2, low, high);
+        CHECK(ret, FAIL, "H5Sget_select_bounds");
+        VERIFY(low[0], 0, "Selection Bounds");
+        VERIFY(low[1], 0, "Selection Bounds");
+        VERIFY(high[0], 9, "Selection Bounds");
+        VERIFY(high[1], 9, "Selection Bounds");
 
-    /* Close region space */
-    ret = H5Sclose(sid2);
-    CHECK(ret, FAIL, "H5Sclose");
+        /* Close region space */
+        ret = H5Sclose(sid2);
+        CHECK(ret, FAIL, "H5Sclose");
 
-    if(libver_high >= H5F_LIBVER_V110) {
         /* Get the unlimited selection */
-        sid2 = H5Rget_region(dset1, H5R_DATASET_REGION, &rbuf[2]);
-        CHECK(sid2, FAIL, "H5Rget_region");
+        sid2 = H5Ropen_region((const H5R_ref_t *)&rbuf[2], H5P_DEFAULT, H5P_DEFAULT);
+        CHECK(sid2, H5I_INVALID_HID, "H5Ropen_region");
 
         /* Verify correct hyperslab selected */
         hssize_ret = H5Sget_select_npoints(sid2);
@@ -867,23 +916,23 @@ test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
         /* Close region space */
         ret = H5Sclose(sid2);
         CHECK(ret, FAIL, "H5Sclose");
-    }
 
-    /* Close first space */
-    ret = H5Sclose(sid1);
-    CHECK(ret, FAIL, "H5Sclose");
-
-    /* Close dereferenced Dataset */
-    ret = H5Dclose(dset2);
-    CHECK(ret, FAIL, "H5Dclose");
+        /* Close first space */
+        ret = H5Sclose(sid1);
+        CHECK(ret, FAIL, "H5Sclose");
 
-    /* Attempting to retrieve type of object using non-valid refs */
-    for(j = 0; j < 3; j++) {
-        H5E_BEGIN_TRY {
-            ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &nvrbuf[j], &obj_type);
-        } H5E_END_TRY;
-        VERIFY(ret, FAIL, "H5Rget_obj_type2");
-    } /* end for */
+        /* Close dereferenced Dataset */
+        ret = H5Dclose(dset2);
+        CHECK(ret, FAIL, "H5Dclose");
+
+        /* Attempting to retrieve type of object using non-valid refs */
+        for(j = 0; j < 3; j++) {
+            H5E_BEGIN_TRY {
+                ret = H5Rget_obj_type3((const H5R_ref_t *)&nvrbuf[j], H5P_DEFAULT, &obj_type);
+            } H5E_END_TRY;
+            VERIFY(ret, FAIL, "H5Rget_obj_type3");
+        } /* end for */
+    }
 
     /* Close Dataset */
     ret = H5Dclose(dset1);
@@ -897,6 +946,16 @@ test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
     ret = H5Fclose(fid1);
     CHECK(ret, FAIL, "H5Fclose");
 
+    /* Destroy references */
+    for(j = 0; j < SPACE1_DIM1; j++) {
+        ret = H5Rdestroy(&wbuf[j]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+        if(libver_high >= H5F_LIBVER_V110) {
+            ret = H5Rdestroy(&rbuf[j]);
+            CHECK(ret, FAIL, "H5Rdestroy");
+        }
+    }
+
     /* Free memory buffers */
     HDfree(wbuf);
     HDfree(rbuf);
@@ -917,14 +976,14 @@ test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
 static void
 test_reference_region_1D(H5F_libver_t libver_low, H5F_libver_t libver_high)
 {
-    hid_t fid1;        /* HDF5 File IDs        */
-    hid_t fapl = -1;    /* File access property list */
-    hid_t dset1,        /* Dataset ID            */
-          dset3;        /* Dereferenced dataset ID */
-    hid_t sid1,         /* Dataspace ID    #1        */
-          sid3;         /* Dataspace ID    #3        */
-    hid_t dapl_id;      /* Dataset access property list */
-    hsize_t dims1[] = {SPACE1_DIM1},
+    hid_t fid1;                     /* HDF5 File IDs        */
+    hid_t fapl;                     /* File access property list */
+    hid_t dset1,                    /* Dataset ID            */
+          dset3;                    /* Dereferenced dataset ID */
+    hid_t sid1,                     /* Dataspace ID    #1        */
+          sid3;                     /* Dataspace ID    #3        */
+    hid_t dapl_id;                  /* Dataset access property list */
+    hsize_t dims1[] = {2},          /* Must be 2 */
             dims3[] = {SPACE3_DIM1};
     hsize_t start[SPACE3_RANK];     /* Starting location of hyperslab */
     hsize_t stride[SPACE3_RANK];    /* Stride of hyperslab */
@@ -934,50 +993,50 @@ test_reference_region_1D(H5F_libver_t libver_low, H5F_libver_t libver_high)
     hsize_t *coords;                /* Coordinate buffer */
     hsize_t low[SPACE3_RANK];       /* Selection bounds */
     hsize_t high[SPACE3_RANK];      /* Selection bounds */
-    hdset_reg_ref_t *wbuf,          /* buffer to write to disk */
-                    *rbuf;          /* buffer read from disk */
-    uint8_t *dwbuf,  /* Buffer for writing numeric data to disk */
-            *drbuf;  /* Buffer for reading numeric data from disk */
-    uint8_t *tu8;    /* Temporary pointer to uint8 data */
+    H5R_ref_t *wbuf,                   /* buffer to write to disk */
+           *rbuf;                   /* buffer read from disk */
+    uint8_t *dwbuf,                 /* Buffer for writing numeric data to disk */
+            *drbuf;                 /* Buffer for reading numeric data from disk */
+    uint8_t *tu8;                   /* Temporary pointer to uint8 data */
     H5O_type_t obj_type;            /* Object type */
-    int i;          /* counting variables */
-    herr_t ret;     /* Generic return value */
+    int i;                          /* Counter */
+    herr_t ret;                     /* Generic return value */
 
     /* Output message about test being performed */
     MESSAGE(5, ("Testing 1-D Dataset Region Reference Functions\n"));
 
     /* Allocate write & read buffers */
-    wbuf = (hdset_reg_ref_t *)HDcalloc(sizeof(hdset_reg_ref_t), (size_t)SPACE1_DIM1);
-    rbuf = (hdset_reg_ref_t *)HDmalloc(sizeof(hdset_reg_ref_t) * SPACE1_DIM1);
-    dwbuf = (uint8_t *)HDmalloc(sizeof(uint8_t) * SPACE3_DIM1);
+    wbuf = (H5R_ref_t *)HDcalloc(sizeof(H5R_ref_t), (size_t)SPACE1_DIM1);
+    rbuf = (H5R_ref_t *)HDcalloc(sizeof(H5R_ref_t), (size_t)SPACE1_DIM1);
+    dwbuf = (uint8_t *)HDcalloc(sizeof(uint8_t), (size_t)SPACE3_DIM1);
     drbuf = (uint8_t *)HDcalloc(sizeof(uint8_t), (size_t)SPACE3_DIM1);
 
+    for(tu8 = dwbuf, i = 0; i < SPACE3_DIM1; i++)
+        *tu8++ = (uint8_t)(i * 3);
+
     /* Create the file access property list */
     fapl = H5Pcreate(H5P_FILE_ACCESS);
-    CHECK(fapl, FAIL, "H5Pcreate");
+    CHECK(fapl, H5I_INVALID_HID, "H5Pcreate");
 
     /* Set the low/high version bounds in fapl */
     ret = H5Pset_libver_bounds(fapl, libver_low, libver_high);
     CHECK(ret, FAIL, "H5Pset_libver_bounds");
 
     /* Create file with the fapl */
-    fid1 = H5Fcreate(FILE2, H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
-    CHECK(fid1, FAIL, "H5Fcreate");
+    fid1 = H5Fcreate(FILE_REF_REG_1D, H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fcreate");
 
     /* Create dataspace for datasets */
     sid3 = H5Screate_simple(SPACE3_RANK, dims3, NULL);
-    CHECK(sid3, FAIL, "H5Screate_simple");
+    CHECK(sid3, H5I_INVALID_HID, "H5Screate_simple");
 
     /* Create dataset access property list */
     dapl_id = H5Pcreate(H5P_DATASET_ACCESS);
-    CHECK(dapl_id, FAIL, "H5Pcreate");
+    CHECK(dapl_id, H5I_INVALID_HID, "H5Pcreate");
 
     /* Create a dataset */
     dset3 = H5Dcreate2(fid1, "Dataset2", H5T_STD_U8LE, sid3, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(dset3, FAIL, "H5Dcreate2");
-
-    for(tu8 = dwbuf, i = 0; i < SPACE3_DIM1; i++)
-        *tu8++ = (uint8_t)(i * 3);
+    CHECK(dset3, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Write selection to disk */
     ret = H5Dwrite(dset3, H5T_STD_U8LE, H5S_ALL, H5S_ALL, H5P_DEFAULT, dwbuf);
@@ -989,31 +1048,31 @@ test_reference_region_1D(H5F_libver_t libver_low, H5F_libver_t libver_high)
 
     /* Create dataspace for the reference dataset */
     sid1 = H5Screate_simple(SPACE1_RANK, dims1, NULL);
-    CHECK(sid1, FAIL, "H5Screate_simple");
+    CHECK(sid1, H5I_INVALID_HID, "H5Screate_simple");
 
     /* Create a dataset */
-    dset1 = H5Dcreate2(fid1, "Dataset1", H5T_STD_REF_DSETREG, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    dset1 = H5Dcreate2(fid1, "Dataset1", H5T_STD_REF, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
     CHECK(ret, FAIL, "H5Dcreate2");
 
     /* Create references */
 
     /* Select 15 2x1 hyperslabs for first reference */
-    start[0] = 2;
+    start[0]  = 2;
     stride[0] = 5;
-    count[0] = 15;
-    block[0] = 2;
+    count[0]  = 15;
+    block[0]  = 2;
     ret = H5Sselect_hyperslab(sid3, H5S_SELECT_SET, start, stride, count, block);
     CHECK(ret, FAIL, "H5Sselect_hyperslab");
 
     ret = (int)H5Sget_select_npoints(sid3);
-    VERIFY(ret, 30, "H5Sget_select_npoints");
+    VERIFY(ret, (block[0] * count[0]), "H5Sget_select_npoints");
 
     /* Store first dataset region */
-    ret = H5Rcreate(&wbuf[0], fid1, "/Dataset2", H5R_DATASET_REGION, sid3);
-    CHECK(ret, FAIL, "H5Rcreate");
-    ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &wbuf[0], &obj_type);
-    CHECK(ret, FAIL, "H5Rget_obj_type2");
-    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+    ret = H5Rcreate_region(fid1, "/Dataset2", sid3, &wbuf[0]);
+    CHECK(ret, FAIL, "H5Rcreate_region");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&wbuf[0], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
 
     /* Select sequence of ten points for second reference */
     coord1[0][0] = 16;
@@ -1030,14 +1089,14 @@ test_reference_region_1D(H5F_libver_t libver_low, H5F_libver_t libver_high)
     CHECK(ret, FAIL, "H5Sselect_elements");
 
     ret = (int)H5Sget_select_npoints(sid3);
-    VERIFY(ret, 10, "H5Sget_select_npoints");
+    VERIFY(ret, POINT1_NPOINTS, "H5Sget_select_npoints");
 
     /* Store second dataset region */
-    ret = H5Rcreate(&wbuf[1], fid1, "/Dataset2", H5R_DATASET_REGION, sid3);
-    CHECK(ret, FAIL, "H5Rcreate");
+    ret = H5Rcreate_region(fid1, "/Dataset2", sid3, &wbuf[1]);
+    CHECK(ret, FAIL, "H5Rcreate_region");
 
     /* Write selection to disk */
-    ret = H5Dwrite(dset1, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
+    ret = H5Dwrite(dset1, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
     CHECK(ret, FAIL, "H5Dwrite");
 
     /* Close disk dataspace */
@@ -1057,32 +1116,32 @@ test_reference_region_1D(H5F_libver_t libver_low, H5F_libver_t libver_high)
     CHECK(ret, FAIL, "H5Fclose");
 
     /* Re-open the file */
-    fid1 = H5Fopen(FILE2, H5F_ACC_RDWR, fapl);
-    CHECK(fid1, FAIL, "H5Fopen");
+    fid1 = H5Fopen(FILE_REF_REG_1D, H5F_ACC_RDWR, fapl);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fopen");
 
     /* Open the dataset */
     dset1 = H5Dopen2(fid1, "/Dataset1", H5P_DEFAULT);
-    CHECK(dset1, FAIL, "H5Dopen2");
+    CHECK(dset1, H5I_INVALID_HID, "H5Dopen2");
 
     /* Read selection from disk */
-    ret = H5Dread(dset1, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf);
+    ret = H5Dread(dset1, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf);
     CHECK(ret, FAIL, "H5Dread");
 
     /* Try to open objects */
-    dset3 = H5Rdereference2(dset1, dapl_id, H5R_DATASET_REGION, &rbuf[0]);
-    CHECK(dset3, FAIL, "H5Rdereference2");
+    dset3 = H5Ropen_object((const H5R_ref_t *)&rbuf[0], H5P_DEFAULT, dapl_id);
+    CHECK(dset3, H5I_INVALID_HID, "H5Ropen_object");
 
-    /* Check what H5Rget_obj_type2 function returns */
-    ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &rbuf[0], &obj_type);
-    CHECK(ret, FAIL, "H5Rget_obj_type2");
-    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+    /* Check what H5Rget_obj_type3 function returns */
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&rbuf[0], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
 
     /* Check information in referenced dataset */
     sid1 = H5Dget_space(dset3);
-    CHECK(sid1, FAIL, "H5Dget_space");
+    CHECK(sid1, H5I_INVALID_HID, "H5Dget_space");
 
     ret = (int)H5Sget_simple_extent_npoints(sid1);
-    VERIFY(ret, 100, "H5Sget_simple_extent_npoints");
+    VERIFY(ret, SPACE3_DIM1, "H5Sget_simple_extent_npoints");
 
     /* Read from disk */
     ret = H5Dread(dset3, H5T_STD_U8LE, H5S_ALL, H5S_ALL, H5P_DEFAULT, drbuf);
@@ -1092,8 +1151,8 @@ test_reference_region_1D(H5F_libver_t libver_low, H5F_libver_t libver_high)
         VERIFY(*tu8, (uint8_t)(i * 3), "Data");
 
     /* Get the hyperslab selection */
-    sid3 = H5Rget_region(dset1, H5R_DATASET_REGION, &rbuf[0]);
-    CHECK(sid3, FAIL, "H5Rget_region");
+    sid3 = H5Ropen_region((const H5R_ref_t *)&rbuf[0], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(sid3, H5I_INVALID_HID, "H5Ropen_region");
 
     /* Verify correct hyperslab selected */
     ret = (int)H5Sget_select_npoints(sid3);
@@ -1144,8 +1203,8 @@ test_reference_region_1D(H5F_libver_t libver_low, H5F_libver_t libver_high)
     CHECK(ret, FAIL, "H5Sclose");
 
     /* Get the element selection */
-    sid3 = H5Rget_region(dset1, H5R_DATASET_REGION, &rbuf[1]);
-    CHECK(sid3, FAIL, "H5Rget_region");
+    sid3 = H5Ropen_region((const H5R_ref_t *)&rbuf[1], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(sid3, H5I_INVALID_HID, "H5Ropen_region");
 
     /* Verify correct elements selected */
     ret = (int)H5Sget_select_npoints(sid3);
@@ -1199,6 +1258,14 @@ test_reference_region_1D(H5F_libver_t libver_low, H5F_libver_t libver_high)
     ret = H5Fclose(fid1);
     CHECK(ret, FAIL, "H5Fclose");
 
+    /* Destroy references */
+    for(i = 0; i < 2; i++) {
+        ret = H5Rdestroy(&wbuf[i]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+        ret = H5Rdestroy(&rbuf[i]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+    }
+
     /* Free memory buffers */
     HDfree(wbuf);
     HDfree(rbuf);
@@ -1215,44 +1282,43 @@ test_reference_region_1D(H5F_libver_t libver_low, H5F_libver_t libver_high)
 static void
 test_reference_obj_deleted(void)
 {
-    hid_t        fid1;        /* HDF5 File IDs        */
-    hid_t        dataset,    /* Dataset ID            */
-                dset2;      /* Dereferenced dataset ID */
-    hid_t        sid1;       /* Dataspace ID            */
-    hobj_ref_t  oref;       /* Object Reference to test */
-    H5O_type_t          obj_type;       /* Object type */
-    haddr_t addr = HADDR_UNDEF; /* test for undefined reference */
-    herr_t        ret;        /* Generic return value        */
+    hid_t       fid1;       /* HDF5 File IDs            */
+    hid_t       dataset,    /* Dataset ID               */
+                dset2;      /* Dereferenced dataset ID  */
+    hid_t       sid1;       /* Dataspace ID             */
+    H5R_ref_t      oref;       /* Object Reference to test */
+    H5O_type_t  obj_type;   /* Object type              */
+    herr_t      ret;        /* Generic return value     */
 
     /* Create file */
-    fid1 = H5Fcreate(FILE3, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(fid1, FAIL, "H5Fcreate");
+    fid1 = H5Fcreate(FILE_REF_OBJ_DEL, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fcreate");
 
     /* Create scalar dataspace for datasets */
     sid1 = H5Screate_simple(0, NULL, NULL);
-    CHECK(sid1, FAIL, "H5Screate_simple");
+    CHECK(sid1, H5I_INVALID_HID, "H5Screate_simple");
 
     /* Create a dataset to reference (deleted later) */
     dataset = H5Dcreate2(fid1, "Dataset1", H5T_NATIVE_INT, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(dataset, FAIL, "H5Dcreate2");
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Close Dataset */
     ret = H5Dclose(dataset);
     CHECK(ret, FAIL, "H5Dclose");
 
     /* Create a dataset */
-    dataset = H5Dcreate2(fid1, "Dataset2", H5T_STD_REF_OBJ, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(dataset, FAIL, "H5Dcreate2");
+    dataset = H5Dcreate2(fid1, "Dataset2", H5T_STD_REF, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Create reference to dataset */
-    ret = H5Rcreate(&oref, fid1, "/Dataset1", H5R_OBJECT, (hid_t)-1);
-    CHECK(ret, FAIL, "H5Rcreate");
-    ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &oref, &obj_type);
-    CHECK(ret, FAIL, "H5Rget_obj_type2");
-    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+    ret = H5Rcreate_object(fid1, "/Dataset1", &oref);
+    CHECK(ret, FAIL, "H5Rcreate_object");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&oref, H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
 
     /* Write selection to disk */
-    ret = H5Dwrite(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, &oref);
+    ret = H5Dwrite(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, &oref);
     CHECK(ret, FAIL, "H5Dwrite");
 
     /* Close Dataset */
@@ -1271,31 +1337,25 @@ test_reference_obj_deleted(void)
     ret = H5Fclose(fid1);
     CHECK(ret, FAIL, "H5Fclose");
 
+    /* Destroy reference */
+    ret = H5Rdestroy(&oref);
+    CHECK(ret, FAIL, "H5Rdestroy");
+
     /* Re-open the file */
-    fid1 = H5Fopen(FILE3, H5F_ACC_RDWR, H5P_DEFAULT);
-    CHECK(fid1, FAIL, "H5Fopen");
+    fid1 = H5Fopen(FILE_REF_OBJ_DEL, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fopen");
 
     /* Open the dataset */
     dataset = H5Dopen2(fid1, "/Dataset2", H5P_DEFAULT);
-    CHECK(ret, FAIL, "H5Dopen2");
-
-    /* Open undefined reference */
-    dset2 = H5Rdereference2(dataset, H5P_DEFAULT, H5R_OBJECT, &addr);
-    VERIFY(dset2, FAIL, "H5Rdereference2");
+    CHECK(ret, H5I_INVALID_HID, "H5Dopen2");
 
     /* Read selection from disk */
-    HDmemset(&oref, 0, sizeof(hobj_ref_t));
-    ret = H5Dread(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, &oref);
+    ret = H5Dread(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, &oref);
     CHECK(ret, FAIL, "H5Dread");
 
     /* Open deleted dataset object */
-    dset2 = H5Rdereference2(dataset, H5P_DEFAULT, H5R_OBJECT, &oref);
-    VERIFY(dset2, FAIL, "H5Rdereference2");
-
-    /* Open nonsense reference */
-    HDmemset(&oref, 0, sizeof(hobj_ref_t));
-    dset2 = H5Rdereference2(dataset, H5P_DEFAULT, H5R_OBJECT, &oref);
-    VERIFY(dset2, FAIL, "H5Rdereference2");
+    dset2 = H5Ropen_object((const H5R_ref_t *)&oref, H5P_DEFAULT, H5P_DEFAULT);
+    VERIFY(dset2, H5I_INVALID_HID, "H5Ropen_object");
 
     /* Close Dataset */
     ret = H5Dclose(dataset);
@@ -1304,6 +1364,10 @@ test_reference_obj_deleted(void)
     /* Close file */
     ret = H5Fclose(fid1);
     CHECK(ret, FAIL, "H5Fclose");
+
+    /* Destroy reference */
+    ret = H5Rdestroy(&oref);
+    CHECK(ret, FAIL, "H5Rdestroy");
 }   /* test_reference_obj_deleted() */
 
 /****************************************************************
@@ -1359,8 +1423,8 @@ test_reference_group(void)
     hid_t gid = -1, gid2 = -1;  /* Group IDs */
     hid_t did;                  /* Dataset ID */
     hid_t sid;                  /* Dataspace ID */
-    hobj_ref_t wref;            /* Reference to write */
-    hobj_ref_t rref;            /* Reference to read */
+    H5R_ref_t wref;                /* Reference to write */
+    H5R_ref_t rref;                /* Reference to read */
     H5G_info_t ginfo;           /* Group info struct */
     char objname[NAME_SIZE];    /* Buffer to store name */
     H5O_info_t oinfo;           /* Object info struct */
@@ -1369,47 +1433,47 @@ test_reference_group(void)
     herr_t ret;
 
     /* Create file with a group and a dataset containing an object reference to the group */
-    fid = H5Fcreate(FILE1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(fid, FAIL, "H5Fcreate");
+    fid = H5Fcreate(FILE_REF_GRP, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid, H5I_INVALID_HID, "H5Fcreate");
 
     /* Create dataspace to use for dataset */
     sid = H5Screate(H5S_SCALAR);
-    CHECK(sid, FAIL, "H5Screate");
+    CHECK(sid, H5I_INVALID_HID, "H5Screate");
 
     /* Create group to refer to */
     gid = H5Gcreate2(fid, GROUPNAME,  H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(gid, FAIL, "H5Gcreate2");
+    CHECK(gid, H5I_INVALID_HID, "H5Gcreate2");
 
     /* Create nested groups */
     gid2 = H5Gcreate2(gid, GROUPNAME2,  H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(gid2, FAIL, "H5Gcreate2");
+    CHECK(gid2, H5I_INVALID_HID, "H5Gcreate2");
     ret = H5Gclose(gid2);
     CHECK(ret, FAIL, "H5Gclose");
 
     gid2 = H5Gcreate2(gid, GROUPNAME3,  H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(gid2, FAIL, "H5Gcreate2");
+    CHECK(gid2, H5I_INVALID_HID, "H5Gcreate2");
     ret = H5Gclose(gid2);
     CHECK(ret, FAIL, "H5Gclose");
 
     /* Create bottom dataset */
     did = H5Dcreate2(gid, DSETNAME2, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    assert(did > 0);
+    CHECK(did, H5I_INVALID_HID, "H5Dcreate2");
     ret = H5Dclose(did);
-    assert(ret >= 0);
+    CHECK(ret, FAIL, "H5Dclose");
 
     ret = H5Gclose(gid);
     CHECK(ret, FAIL, "H5Gclose");
 
     /* Create dataset */
-    did = H5Dcreate2(fid, DSETNAME, H5T_STD_REF_OBJ, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(did, FAIL, "H5Dcreate2");
+    did = H5Dcreate2(fid, DSETNAME, H5T_STD_REF, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(did, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Create reference to group */
-    ret = H5Rcreate(&wref, fid, GROUPNAME, H5R_OBJECT, (hid_t)-1);
-    CHECK(ret, FAIL, "H5Rcreate");
+    ret = H5Rcreate_object(fid, GROUPNAME, &wref);
+    CHECK(ret, FAIL, "H5Rcreate_object");
 
     /* Write reference to disk */
-    ret = H5Dwrite(did, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, &wref);
+    ret = H5Dwrite(did, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, &wref);
     CHECK(ret, FAIL, "H5Dwrite");
 
     /* Close objects */
@@ -1420,22 +1484,25 @@ test_reference_group(void)
     ret = H5Fclose(fid);
     CHECK(ret, FAIL, "H5Fclose");
 
+    /* Destroy reference */
+    ret = H5Rdestroy(&wref);
+    CHECK(ret, FAIL, "H5Rdestroy");
 
     /* Re-open file */
-    fid = H5Fopen(FILE1, H5F_ACC_RDWR, H5P_DEFAULT);
-    CHECK(fid, FAIL, "H5Fopen");
+    fid = H5Fopen(FILE_REF_GRP, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK(fid, H5I_INVALID_HID, "H5Fopen");
 
     /* Re-open dataset */
     did = H5Dopen2(fid, DSETNAME, H5P_DEFAULT);
-    CHECK(did, FAIL, "H5Dopen2");
+    CHECK(did, H5I_INVALID_HID, "H5Dopen2");
 
     /* Read in the reference */
-    ret = H5Dread(did, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, &rref);
+    ret = H5Dread(did, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, &rref);
     CHECK(ret, FAIL, "H5Dread");
 
     /* Dereference to get the group */
-    gid = H5Rdereference2(did, H5P_DEFAULT, H5R_OBJECT, &rref);
-    CHECK(gid, FAIL, "H5Rdereference2");
+    gid = H5Ropen_object((const H5R_ref_t *)&rref, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(gid, H5I_INVALID_HID, "H5Ropen_object");
 
     /* Iterate through objects in dereferenced group */
     ret = H5Literate(gid, H5_INDEX_NAME, H5_ITER_INC, NULL, test_deref_iter_op, &count);
@@ -1447,7 +1514,7 @@ test_reference_group(void)
     VERIFY(ginfo.nlinks, 3, "H5Gget_info");
 
     size = H5Lget_name_by_idx(gid, ".", H5_INDEX_NAME, H5_ITER_INC, (hsize_t)0, objname, (size_t)NAME_SIZE, H5P_DEFAULT);
-    CHECK(size, FAIL, "H5Lget_name_by_idx");
+    CHECK(size, (-1), "H5Lget_name_by_idx");
     VERIFY_STR(objname, DSETNAME2, "H5Lget_name_by_idx");
 
     ret = H5Oget_info_by_idx2(gid, ".", H5_INDEX_NAME, H5_ITER_INC, (hsize_t)0, &oinfo, H5O_INFO_BASIC, H5P_DEFAULT);
@@ -1469,66 +1536,618 @@ test_reference_group(void)
     CHECK(ret, FAIL, "H5Gclose");
     ret = H5Fclose(fid);
     CHECK(ret, FAIL, "H5Fclose");
+
+    /* Destroy reference */
+    ret = H5Rdestroy(&rref);
+    CHECK(ret, FAIL, "H5Rdestroy");
 }   /* test_reference_group() */
 
-#ifndef H5_NO_DEPRECATED_SYMBOLS
 /****************************************************************
 **
-**  test_reference_compat(): Test basic H5R (reference) object reference code.
-**      Tests deprecated API routines
+**  test_reference_attr(): Test basic H5R (reference) attribute reference code.
+**      Tests references to attributes on various kinds of objects
 **
 ****************************************************************/
 static void
-test_reference_compat(void)
+test_reference_attr(void)
 {
-    hid_t    fid1;        /* HDF5 File IDs        */
-    hid_t    dataset, dset2;    /* Dataset ID            */
-    hid_t    group, group2;  /* Group ID                     */
-    hid_t    sid1,           /* Dataspace IDs        */
-                sid2;
-    hid_t    tid1, tid2;     /* Datatype ID            */
-    hsize_t    dims1[] = {SPACE1_DIM1},
-                dims2[] = {SPACE2_DIM1, SPACE2_DIM2};
-    hsize_t    start[SPACE2_RANK];     /* Starting location of hyperslab */
-    hsize_t    stride[SPACE2_RANK];    /* Stride of hyperslab */
-    hsize_t    count[SPACE2_RANK];     /* Element count of hyperslab */
-    hsize_t    block[SPACE2_RANK];     /* Block size of hyperslab */
-    hsize_t    coord1[POINT1_NPOINTS][SPACE2_RANK]; /* Coordinates for point selection */
-    hobj_ref_t *wbuf_obj,       /* Buffer to write to disk */
-               *rbuf_obj;       /* Buffer read from disk */
-    hdset_reg_ref_t *wbuf_reg,  /* Buffer to write to disk */
-               *rbuf_reg;       /* Buffer read from disk */
-    H5G_obj_t   obj_type;       /* Object type */
-    herr_t    ret;        /* Generic return value        */
+    hid_t       fid;        /* HDF5 File ID */
+    hid_t       dataset;    /* Dataset ID */
+    hid_t       group;      /* Group ID */
+    hid_t       attr;       /* Attribute ID */
+    hid_t       sid;        /* Dataspace ID */
+    hid_t       tid;        /* Datatype ID */
+    hsize_t     dims[] = {SPACE1_DIM1};
+    hid_t       dapl_id;    /* Dataset access property list */
+    H5R_ref_t      ref_wbuf[SPACE1_DIM1], /* Buffer to write to disk */
+                ref_rbuf[SPACE1_DIM1]; /* Buffer read from disk */
+    unsigned    wbuf[SPACE1_DIM1], rbuf[SPACE1_DIM1];
+    unsigned    *tu32;      /* Temporary pointer to uint32 data */
+    int         i;          /* Local index variables */
+    H5O_type_t  obj_type;   /* Object type */
+    herr_t      ret;        /* Generic return value */
+
+    /* Output message about test being performed */
+    MESSAGE(5, ("Testing Attribute Reference Functions\n"));
+
+    /* Create file */
+    fid = H5Fcreate(FILE_REF_ATTR, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid, H5I_INVALID_HID, "H5Fcreate");
+
+    /* Create dataspace for datasets */
+    sid = H5Screate_simple(SPACE1_RANK, dims, NULL);
+    CHECK(sid, H5I_INVALID_HID, "H5Screate_simple");
+
+    /* Create dataset access property list */
+    dapl_id = H5Pcreate(H5P_DATASET_ACCESS);
+    CHECK(dapl_id, H5I_INVALID_HID, "H5Pcreate");
+
+    /* Create a group */
+    group = H5Gcreate2(fid, "Group1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(group, H5I_INVALID_HID, "H5Gcreate2");
+
+    /* Create an attribute for the dataset */
+    attr = H5Acreate2(group, "Attr2", H5T_NATIVE_UINT, sid, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Acreate2");
+
+    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
+        *tu32++ = (unsigned)((i * 3) + 1);
+
+    /* Write attribute to disk */
+    ret = H5Awrite(attr, H5T_NATIVE_UINT, wbuf);
+    CHECK(ret, FAIL, "H5Awrite");
+
+    /* Close attribute */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Create a dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset1", H5T_NATIVE_UINT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    /* Create an attribute for the dataset */
+    attr = H5Acreate2(dataset, "Attr1", H5T_NATIVE_UINT, sid, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Acreate2");
+
+    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
+        *tu32++ = (unsigned)(i * 3);
+
+    /* Write attribute to disk */
+    ret = H5Awrite(attr, H5T_NATIVE_UINT, wbuf);
+    CHECK(ret, FAIL, "H5Awrite");
+
+    /* Close attribute */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create another dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset2", H5T_NATIVE_UCHAR, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create a datatype to refer to */
+    tid = H5Tcreate(H5T_COMPOUND, sizeof(s1_t));
+    CHECK(tid, H5I_INVALID_HID, "H5Tcreate");
+
+    /* Insert fields */
+    ret = H5Tinsert(tid, "a", HOFFSET(s1_t,a), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid, "b", HOFFSET(s1_t,b), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid, "c", HOFFSET(s1_t,c), H5T_NATIVE_FLOAT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    /* Save datatype for later */
+    ret = H5Tcommit2(group, "Datatype1", tid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Tcommit2");
+
+    /* Create an attribute for the datatype */
+    attr = H5Acreate2(tid, "Attr3", H5T_NATIVE_UINT, sid, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Acreate2");
+
+    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
+        *tu32++ = (unsigned)((i * 3) + 2);
+
+    /* Write attribute to disk */
+    ret = H5Awrite(attr, H5T_NATIVE_UINT, wbuf);
+    CHECK(ret, FAIL, "H5Awrite");
+
+    /* Close attribute */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Close datatype */
+    ret = H5Tclose(tid);
+    CHECK(ret, FAIL, "H5Tclose");
+
+    /* Close group */
+    ret = H5Gclose(group);
+    CHECK(ret, FAIL, "H5Gclose");
+
+    /* Create a dataset */
+    dataset = H5Dcreate2(fid, "Dataset3", H5T_STD_REF, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    /* Create reference to dataset1 attribute */
+    ret = H5Rcreate_attr(fid, "/Group1/Dataset1", "Attr1", &ref_wbuf[0]);
+    CHECK(ret, FAIL, "H5Rcreate_attr");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&ref_wbuf[0], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
+
+    /* Create reference to dataset2 attribute */
+    ret = H5Rcreate_attr(fid, "/Group1/Dataset2", "Attr1", &ref_wbuf[1]);
+    CHECK(ret, FAIL, "H5Rcreate_attr");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&ref_wbuf[1], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
+
+    /* Create reference to group attribute */
+    ret = H5Rcreate_attr(fid, "/Group1", "Attr2", &ref_wbuf[2]);
+    CHECK(ret, FAIL, "H5Rcreate_attr");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&ref_wbuf[2], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_GROUP, "H5Rget_obj_type3");
+
+    /* Create reference to named datatype attribute */
+    ret = H5Rcreate_attr(fid, "/Group1/Datatype1", "Attr3", &ref_wbuf[3]);
+    CHECK(ret, FAIL, "H5Rcreate_attr");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&ref_wbuf[3], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_NAMED_DATATYPE, "H5Rget_obj_type3");
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, ref_wbuf);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close disk dataspace */
+    ret = H5Sclose(sid);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close file */
+    ret = H5Fclose(fid);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Re-open the file */
+    fid = H5Fopen(FILE_REF_ATTR, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK(fid, FAIL, "H5Fopen");
+
+    /* Open the dataset */
+    dataset = H5Dopen2(fid, "/Dataset3", H5P_DEFAULT);
+    CHECK(ret, H5I_INVALID_HID, "H5Dopen2");
+
+    /* Read selection from disk */
+    ret = H5Dread(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, ref_rbuf);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /* Open attribute on dataset object */
+    attr = H5Ropen_attr((const H5R_ref_t *)&ref_rbuf[0], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Ropen_attr");
+
+    /* Check information in referenced dataset */
+    sid = H5Aget_space(attr);
+    CHECK(sid, H5I_INVALID_HID, "H5Aget_space");
+
+    ret = (int)H5Sget_simple_extent_npoints(sid);
+    VERIFY(ret, SPACE1_DIM1, "H5Sget_simple_extent_npoints");
+
+    /* Read from disk */
+    ret = H5Aread(attr, H5T_NATIVE_UINT, rbuf);
+    CHECK(ret, FAIL, "H5Aread");
+
+    for(tu32 = (unsigned *)rbuf, i = 0; i < SPACE1_DIM1; i++, tu32++)
+        VERIFY(*tu32, (uint32_t)(i * 3), "Data");
+
+    /* Close dereferenced Dataset */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Open attribute on group object */
+    attr = H5Ropen_attr((const H5R_ref_t *)&ref_rbuf[2], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Ropen_attr");
+
+    /* Read from disk */
+    ret = H5Aread(attr, H5T_NATIVE_UINT, rbuf);
+    CHECK(ret, FAIL, "H5Aread");
+
+    for(tu32 = (unsigned *)rbuf, i = 0; i < SPACE1_DIM1; i++, tu32++)
+        VERIFY(*tu32, (uint32_t)((i * 3) + 1), "Data");
+
+    /* Close attribute  */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Open attribute on named datatype object */
+    attr = H5Ropen_attr((const H5R_ref_t *)&ref_rbuf[3], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Ropen_attr");
+
+    /* Read from disk */
+    ret = H5Aread(attr, H5T_NATIVE_UINT, rbuf);
+    CHECK(ret, FAIL, "H5Aread");
+
+    for(tu32 = (unsigned *)rbuf, i = 0; i < SPACE1_DIM1; i++, tu32++)
+        VERIFY(*tu32, (uint32_t)((i * 3) + 2), "Data");
+
+    /* Close attribute  */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Close dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close dataset access property list */
+    ret = H5Pclose(dapl_id);
+    CHECK(ret, FAIL, "H5Pclose");
+
+    /* Close file */
+    ret = H5Fclose(fid);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Free memory buffers */
+    for (i = 0; i < SPACE1_DIM1; i++) {
+        ret = H5Rdestroy(&ref_wbuf[i]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+        ret = H5Rdestroy(&ref_rbuf[i]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+    }
+}   /* test_reference_attr() */
+
+/****************************************************************
+**
+**  test_reference_external():
+**      Tests external references on various kinds of objects
+**
+****************************************************************/
+static void
+test_reference_external(void)
+{
+    hid_t       fid1, fid2; /* HDF5 File ID */
+    hid_t       dataset;    /* Dataset ID */
+    hid_t       group;      /* Group ID */
+    hid_t       attr;       /* Attribute ID */
+    hid_t       sid;        /* Dataspace ID */
+    hid_t       tid;        /* Datatype ID */
+    hsize_t     dims[] = {SPACE1_DIM1};
+    hid_t       dapl_id;    /* Dataset access property list */
+    H5R_ref_t      ref_wbuf[SPACE1_DIM1], /* Buffer to write to disk */
+                ref_rbuf[SPACE1_DIM1]; /* Buffer read from disk */
+    unsigned    wbuf[SPACE1_DIM1], rbuf[SPACE1_DIM1];
+    unsigned    *tu32;      /* Temporary pointer to uint32 data */
+    int         i;          /* Local index variables */
+    H5O_type_t  obj_type;   /* Object type */
+    herr_t      ret;        /* Generic return value */
+
+    /* Output message about test being performed */
+    MESSAGE(5, ("Testing External References Functions\n"));
+
+    /* Create file */
+    fid1 = H5Fcreate(FILE_REF_EXT1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fcreate");
+
+    /* Create dataspace for datasets */
+    sid = H5Screate_simple(SPACE1_RANK, dims, NULL);
+    CHECK(sid, H5I_INVALID_HID, "H5Screate_simple");
+
+    /* Create dataset access property list */
+    dapl_id = H5Pcreate(H5P_DATASET_ACCESS);
+    CHECK(dapl_id, H5I_INVALID_HID, "H5Pcreate");
+
+    /* Create a group */
+    group = H5Gcreate2(fid1, "Group1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(group, H5I_INVALID_HID, "H5Gcreate2");
+
+    /* Create an attribute for the dataset */
+    attr = H5Acreate2(group, "Attr2", H5T_NATIVE_UINT, sid, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Acreate2");
+
+    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
+        *tu32++ = (unsigned)((i * 3) + 1);
+
+    /* Write attribute to disk */
+    ret = H5Awrite(attr, H5T_NATIVE_UINT, wbuf);
+    CHECK(ret, FAIL, "H5Awrite");
+
+    /* Close attribute */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Create a dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset1", H5T_NATIVE_UINT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    /* Create an attribute for the dataset */
+    attr = H5Acreate2(dataset, "Attr1", H5T_NATIVE_UINT, sid, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Acreate2");
+
+    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
+        *tu32++ = (unsigned)(i * 3);
+
+    /* Write attribute to disk */
+    ret = H5Awrite(attr, H5T_NATIVE_UINT, wbuf);
+    CHECK(ret, FAIL, "H5Awrite");
+
+    /* Close attribute */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create another dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset2", H5T_NATIVE_UCHAR, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create a datatype to refer to */
+    tid = H5Tcreate(H5T_COMPOUND, sizeof(s1_t));
+    CHECK(tid, H5I_INVALID_HID, "H5Tcreate");
+
+    /* Insert fields */
+    ret = H5Tinsert(tid, "a", HOFFSET(s1_t,a), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid, "b", HOFFSET(s1_t,b), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid, "c", HOFFSET(s1_t,c), H5T_NATIVE_FLOAT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    /* Save datatype for later */
+    ret = H5Tcommit2(group, "Datatype1", tid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Tcommit2");
+
+    /* Create an attribute for the datatype */
+    attr = H5Acreate2(tid, "Attr3", H5T_NATIVE_UINT, sid, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Acreate2");
+
+    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
+        *tu32++ = (unsigned)((i * 3) + 2);
+
+    /* Write attribute to disk */
+    ret = H5Awrite(attr, H5T_NATIVE_UINT, wbuf);
+    CHECK(ret, FAIL, "H5Awrite");
+
+    /* Close attribute */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Close datatype */
+    ret = H5Tclose(tid);
+    CHECK(ret, FAIL, "H5Tclose");
+
+    /* Close group */
+    ret = H5Gclose(group);
+    CHECK(ret, FAIL, "H5Gclose");
+
+    /* Create reference to dataset1 attribute */
+    ret = H5Rcreate_attr(fid1, "/Group1/Dataset1", "Attr1", &ref_wbuf[0]);
+    CHECK(ret, FAIL, "H5Rcreate_attr");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&ref_wbuf[0], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
+
+    /* Create reference to dataset2 attribute */
+    ret = H5Rcreate_attr(fid1, "/Group1/Dataset2", "Attr1", &ref_wbuf[1]);
+    CHECK(ret, FAIL, "H5Rcreate_attr");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&ref_wbuf[1], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
+
+    /* Create reference to group attribute */
+    ret = H5Rcreate_attr(fid1, "/Group1", "Attr2", &ref_wbuf[2]);
+    CHECK(ret, FAIL, "H5Rcreate_attr");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&ref_wbuf[2], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_GROUP, "H5Rget_obj_type3");
+
+    /* Create reference to named datatype attribute */
+    ret = H5Rcreate_attr(fid1, "/Group1/Datatype1", "Attr3", &ref_wbuf[3]);
+    CHECK(ret, FAIL, "H5Rcreate_attr");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&ref_wbuf[3], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_NAMED_DATATYPE, "H5Rget_obj_type3");
+
+    /* Close disk dataspace */
+    ret = H5Sclose(sid);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Create file */
+    fid2 = H5Fcreate(FILE_REF_EXT2, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid2, H5I_INVALID_HID, "H5Fcreate");
+
+    /* Create dataspace for datasets */
+    sid = H5Screate_simple(SPACE1_RANK, dims, NULL);
+    CHECK(sid, H5I_INVALID_HID, "H5Screate_simple");
+
+    /* Create a dataset */
+    dataset = H5Dcreate2(fid2, "Dataset3", H5T_STD_REF, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, ref_wbuf);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close disk dataspace */
+    ret = H5Sclose(sid);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close file */
+    ret = H5Fclose(fid2);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Re-open the file */
+    fid2 = H5Fopen(FILE_REF_EXT2, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK(fid2, FAIL, "H5Fopen");
+
+    /* Open the dataset */
+    dataset = H5Dopen2(fid2, "/Dataset3", H5P_DEFAULT);
+    CHECK(ret, H5I_INVALID_HID, "H5Dopen2");
+
+    /* Read selection from disk */
+    ret = H5Dread(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, ref_rbuf);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /* Open attribute on dataset object */
+    attr = H5Ropen_attr((const H5R_ref_t *)&ref_rbuf[0], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Ropen_attr");
+
+    /* Check information in referenced dataset */
+    sid = H5Aget_space(attr);
+    CHECK(sid, H5I_INVALID_HID, "H5Aget_space");
+
+    ret = (int)H5Sget_simple_extent_npoints(sid);
+    VERIFY(ret, SPACE1_DIM1, "H5Sget_simple_extent_npoints");
+
+    /* Read from disk */
+    ret = H5Aread(attr, H5T_NATIVE_UINT, rbuf);
+    CHECK(ret, FAIL, "H5Aread");
+
+    for(tu32 = (unsigned *)rbuf, i = 0; i < SPACE1_DIM1; i++, tu32++)
+        VERIFY(*tu32, (uint32_t)(i * 3), "Data");
+
+    /* Close dereferenced Dataset */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Open attribute on group object */
+    attr = H5Ropen_attr((const H5R_ref_t *)&ref_rbuf[2], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Ropen_attr");
+
+    /* Read from disk */
+    ret = H5Aread(attr, H5T_NATIVE_UINT, rbuf);
+    CHECK(ret, FAIL, "H5Aread");
+
+    for(tu32 = (unsigned *)rbuf, i = 0; i < SPACE1_DIM1; i++, tu32++)
+        VERIFY(*tu32, (uint32_t)((i * 3) + 1), "Data");
+
+    /* Close attribute  */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Open attribute on named datatype object */
+    attr = H5Ropen_attr((const H5R_ref_t *)&ref_rbuf[3], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(attr, H5I_INVALID_HID, "H5Ropen_attr");
+
+    /* Read from disk */
+    ret = H5Aread(attr, H5T_NATIVE_UINT, rbuf);
+    CHECK(ret, FAIL, "H5Aread");
+
+    for(tu32 = (unsigned *)rbuf, i = 0; i < SPACE1_DIM1; i++, tu32++)
+        VERIFY(*tu32, (uint32_t)((i * 3) + 2), "Data");
+
+    /* Close attribute  */
+    ret = H5Aclose(attr);
+    CHECK(ret, FAIL, "H5Aclose");
+
+    /* Close dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close dataset access property list */
+    ret = H5Pclose(dapl_id);
+    CHECK(ret, FAIL, "H5Pclose");
+
+    /* Close file */
+    ret = H5Fclose(fid2);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Free memory buffers */
+    for (i = 0; i < SPACE1_DIM1; i++) {
+        ret = H5Rdestroy(&ref_wbuf[i]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+        ret = H5Rdestroy(&ref_rbuf[i]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+    }
+}   /* test_reference_external() */
+
+/****************************************************************
+**
+**  test_reference_compat_conv(): Test basic H5R (reference) object reference code.
+**      Tests deprecated API routines and type conversion.
+**
+****************************************************************/
+static void
+test_reference_compat_conv(void)
+{
+    hid_t   fid1;               /* HDF5 File IDs            */
+    hid_t   dataset, dset2;     /* Dataset ID               */
+    hid_t   group, group2;      /* Group ID                 */
+    hid_t   sid1, sid2, sid3;   /* Dataspace IDs            */
+    hid_t   tid1, tid2;         /* Datatype ID              */
+    hsize_t dims1[] = {SPACE1_DIM1},
+            dims2[] = {SPACE2_DIM1, SPACE2_DIM2},
+            dims3[] = {2};
+    hsize_t start[SPACE2_RANK]; /* Starting location of hyperslab */
+    hsize_t stride[SPACE2_RANK];/* Stride of hyperslab      */
+    hsize_t count[SPACE2_RANK]; /* Element count of hyperslab */
+    hsize_t block[SPACE2_RANK]; /* Block size of hyperslab  */
+    hsize_t coord1[POINT1_NPOINTS][SPACE2_RANK]; /* Coordinates for point selection */
+    hobj_ref_t *wbuf_obj;       /* Buffer to write to disk  */
+    H5R_ref_t     *rbuf_obj;       /* Buffer read from disk    */
+    hdset_reg_ref_t  *wbuf_reg; /* Buffer to write to disk  */
+    H5R_ref_t           *rbuf_reg; /* Buffer read from disk    */
+    H5O_type_t       obj_type;  /* Object type              */
+    herr_t  ret;                /* Generic return value     */
+    unsigned int     i;         /* Counter                  */
 
     /* Output message about test being performed */
     MESSAGE(5, ("Testing Deprecated Object Reference Functions\n"));
 
     /* Allocate write & read buffers */
     wbuf_obj = (hobj_ref_t *)HDcalloc(sizeof(hobj_ref_t), SPACE1_DIM1);
-    rbuf_obj = (hobj_ref_t *)HDmalloc(sizeof(hobj_ref_t) * SPACE1_DIM1);
-    wbuf_reg = (hdset_reg_ref_t *)HDcalloc(sizeof(hdset_reg_ref_t), SPACE1_DIM1);
-    rbuf_reg = (hdset_reg_ref_t *)HDmalloc(sizeof(hdset_reg_ref_t) * SPACE1_DIM1);
+    rbuf_obj = (H5R_ref_t *)HDcalloc(sizeof(H5R_ref_t), SPACE1_DIM1);
+    wbuf_reg = (hdset_reg_ref_t *)HDcalloc(sizeof(hdset_reg_ref_t), 2);
+    rbuf_reg = (H5R_ref_t *)HDcalloc(sizeof(H5R_ref_t), 2);
 
     /* Create file */
-    fid1 = H5Fcreate(FILE1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(fid1, FAIL, "H5Fcreate");
+    fid1 = H5Fcreate(FILE_REF_COMPAT, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fcreate");
 
     /* Create dataspace for datasets */
     sid1 = H5Screate_simple(SPACE1_RANK, dims1, NULL);
-    CHECK(sid1, FAIL, "H5Screate_simple");
+    CHECK(sid1, H5I_INVALID_HID, "H5Screate_simple");
 
     /* Create another dataspace for datasets */
     sid2 = H5Screate_simple(SPACE2_RANK, dims2, NULL);
-    CHECK(sid2, FAIL, "H5Screate_simple");
+    CHECK(sid2, H5I_INVALID_HID, "H5Screate_simple");
+
+    /* Create another dataspace for datasets */
+    sid3 = H5Screate_simple(SPACE1_RANK, dims3, NULL);
+    CHECK(sid3, H5I_INVALID_HID, "H5Screate_simple");
 
     /* Create a group */
     group = H5Gcreate2(fid1, "Group1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(group, FAIL, "H5Gcreate2");
+    CHECK(group, H5I_INVALID_HID, "H5Gcreate2");
 
     /* Create a dataset (inside Group1) */
     dataset = H5Dcreate2(group, "Dataset1", H5T_NATIVE_UINT, sid2, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(dataset, FAIL, "H5Dcreate2");
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Close Dataset */
     ret = H5Dclose(dataset);
@@ -1536,7 +2155,7 @@ test_reference_compat(void)
 
     /* Create another dataset (inside Group1) */
     dataset = H5Dcreate2(group, "Dataset2", H5T_NATIVE_UCHAR, sid2, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(dataset, FAIL, "H5Dcreate2");
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Close Dataset */
     ret = H5Dclose(dataset);
@@ -1544,7 +2163,7 @@ test_reference_compat(void)
 
     /* Create a datatype to refer to */
     tid1 = H5Tcreate(H5T_COMPOUND, sizeof(s1_t));
-    CHECK(tid1, FAIL, "H5Tcreate");
+    CHECK(tid1, H5I_INVALID_HID, "H5Tcreate");
 
     /* Insert fields */
     ret = H5Tinsert(tid1, "a", HOFFSET(s1_t,a), H5T_NATIVE_INT);
@@ -1568,25 +2187,24 @@ test_reference_compat(void)
     ret = H5Gclose(group);
     CHECK(ret, FAIL, "H5Gclose");
 
-
     /* Create a dataset with object reference datatype */
     dataset = H5Dcreate2(fid1, "Dataset3", H5T_STD_REF_OBJ, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(ret, FAIL, "H5Dcreate2");
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
 
     /* Create reference to dataset */
-    ret = H5Rcreate(&wbuf_obj[0], fid1, "/Group1/Dataset1", H5R_OBJECT, (hid_t)-1);
+    ret = H5Rcreate(&wbuf_obj[0], fid1, "/Group1/Dataset1", H5R_OBJECT, H5I_INVALID_HID);
     CHECK(ret, FAIL, "H5Rcreate");
 
     /* Create reference to dataset */
-    ret = H5Rcreate(&wbuf_obj[1], fid1, "/Group1/Dataset2", H5R_OBJECT, (hid_t)-1);
+    ret = H5Rcreate(&wbuf_obj[1], fid1, "/Group1/Dataset2", H5R_OBJECT, H5I_INVALID_HID);
     CHECK(ret, FAIL, "H5Rcreate");
 
     /* Create reference to group */
-    ret = H5Rcreate(&wbuf_obj[2], fid1, "/Group1", H5R_OBJECT, (hid_t)-1);
+    ret = H5Rcreate(&wbuf_obj[2], fid1, "/Group1", H5R_OBJECT, H5I_INVALID_HID);
     CHECK(ret, FAIL, "H5Rcreate");
 
     /* Create reference to named datatype */
-    ret = H5Rcreate(&wbuf_obj[3], fid1, "/Group1/Datatype1", H5R_OBJECT, (hid_t)-1);
+    ret = H5Rcreate(&wbuf_obj[3], fid1, "/Group1/Datatype1", H5R_OBJECT, H5I_INVALID_HID);
     CHECK(ret, FAIL, "H5Rcreate");
 
     /* Write references to disk */
@@ -1597,16 +2215,19 @@ test_reference_compat(void)
     ret = H5Dclose(dataset);
     CHECK(ret, FAIL, "H5Dclose");
 
-
     /* Create a dataset with region reference datatype */
-    dataset = H5Dcreate2(fid1, "Dataset4", H5T_STD_REF_DSETREG, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK(ret, FAIL, "H5Dcreate2");
+    dataset = H5Dcreate2(fid1, "Dataset4", H5T_STD_REF_DSETREG, sid3, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
 
     /* Select 6x6 hyperslab for first reference */
-    start[0] = 2; start[1] = 2;
-    stride[0] = 1; stride[1] = 1;
-    count[0] = 1; count[1] = 1;
-    block[0] = 6; block[1] = 6;
+    start[0]  = 2;
+    start[1]  = 2;
+    stride[0] = 1;
+    stride[1] = 1;
+    count[0]  = 1;
+    count[1]  = 1;
+    block[0]  = 6;
+    block[1]  = 6;
     ret = H5Sselect_hyperslab(sid2, H5S_SELECT_SET, start, stride, count, block);
     CHECK(ret, FAIL, "H5Sselect_hyperslab");
 
@@ -1640,69 +2261,69 @@ test_reference_compat(void)
     ret = H5Dclose(dataset);
     CHECK(ret, FAIL, "H5Dclose");
 
-
     /* Close disk dataspaces */
     ret = H5Sclose(sid1);
     CHECK(ret, FAIL, "H5Sclose");
     ret = H5Sclose(sid2);
     CHECK(ret, FAIL, "H5Sclose");
+    ret = H5Sclose(sid3);
+    CHECK(ret, FAIL, "H5Sclose");
 
     /* Close file */
     ret = H5Fclose(fid1);
     CHECK(ret, FAIL, "H5Fclose");
 
-
     /* Re-open the file */
-    fid1 = H5Fopen(FILE1, H5F_ACC_RDWR, H5P_DEFAULT);
+    fid1 = H5Fopen(FILE_REF_COMPAT, H5F_ACC_RDWR, H5P_DEFAULT);
     CHECK(fid1, FAIL, "H5Fopen");
 
     /* Open the object reference dataset */
     dataset = H5Dopen2(fid1, "/Dataset3", H5P_DEFAULT);
-    CHECK(ret, FAIL, "H5Dopen2");
+    CHECK(dataset, FAIL, "H5Dopen2");
 
     /* Read selection from disk */
-    ret = H5Dread(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf_obj);
+    ret = H5Dread(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf_obj);
     CHECK(ret, FAIL, "H5Dread");
 
     /* Verify type of objects pointed at */
-    obj_type = H5Rget_obj_type1(dataset, H5R_OBJECT, &rbuf_obj[0]);
-    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
-    VERIFY(obj_type, H5G_DATASET, "H5Rget_obj_type1");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&rbuf_obj[0], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
 
-    obj_type = H5Rget_obj_type1(dataset, H5R_OBJECT, &rbuf_obj[1]);
-    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
-    VERIFY(obj_type, H5G_DATASET, "H5Rget_obj_type1");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&rbuf_obj[1], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
 
-    obj_type = H5Rget_obj_type1(dataset, H5R_OBJECT, &rbuf_obj[2]);
-    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
-    VERIFY(obj_type, H5G_GROUP, "H5Rget_obj_type1");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&rbuf_obj[2], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_GROUP, "H5Rget_obj_type3");
 
-    obj_type = H5Rget_obj_type1(dataset, H5R_OBJECT, &rbuf_obj[3]);
-    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
-    VERIFY(obj_type, H5G_TYPE, "H5Rget_obj_type1");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&rbuf_obj[3], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_NAMED_DATATYPE, "H5Rget_obj_type3");
 
 
     /* Make sure the referenced objects can be opened */
-    dset2 = H5Rdereference1(dataset, H5R_OBJECT, &rbuf_obj[0]);
-    CHECK(dset2, FAIL, "H5Rdereference1");
+    dset2 = H5Ropen_object((const H5R_ref_t *)&rbuf_obj[0], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dset2, H5I_INVALID_HID, "H5Ropen_object");
 
     ret = H5Dclose(dset2);
     CHECK(ret, FAIL, "H5Dclose");
 
-    dset2 = H5Rdereference1(dataset, H5R_OBJECT, &rbuf_obj[1]);
-    CHECK(dset2, FAIL, "H5Rdereference1");
+    dset2 = H5Ropen_object((const H5R_ref_t *)&rbuf_obj[1], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dset2, H5I_INVALID_HID, "H5Ropen_object");
 
     ret = H5Dclose(dset2);
     CHECK(ret, FAIL, "H5Dclose");
 
-    group2 = H5Rdereference1(dataset, H5R_OBJECT, &rbuf_obj[2]);
-    CHECK(group2, FAIL, "H5Rdereference1");
+    group2 = H5Ropen_object((const H5R_ref_t *)&rbuf_obj[2], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(group2, H5I_INVALID_HID, "H5Ropen_object");
 
     ret = H5Gclose(group2);
     CHECK(ret, FAIL, "H5Gclose");
 
-    tid2 = H5Rdereference1(dataset, H5R_OBJECT, &rbuf_obj[3]);
-    CHECK(tid2, FAIL, "H5Rdereference1");
+    tid2 = H5Ropen_object((const H5R_ref_t *)&rbuf_obj[3], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(tid2, H5I_INVALID_HID, "H5Ropen_object");
 
     ret = H5Tclose(tid2);
     CHECK(ret, FAIL, "H5Tclose");
@@ -1714,36 +2335,30 @@ test_reference_compat(void)
 
     /* Open the dataset region reference dataset */
     dataset = H5Dopen2(fid1, "/Dataset4", H5P_DEFAULT);
-    CHECK(ret, FAIL, "H5Dopen2");
+    CHECK(ret, H5I_INVALID_HID, "H5Dopen2");
 
     /* Read selection from disk */
-    ret = H5Dread(dataset, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf_reg);
+    ret = H5Dread(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf_reg);
     CHECK(ret, FAIL, "H5Dread");
 
     /* Verify type of objects pointed at */
-    obj_type = H5Rget_obj_type1(dataset, H5R_DATASET_REGION, &rbuf_reg[0]);
-    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
-    VERIFY(obj_type, H5G_DATASET, "H5Rget_obj_type1");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&rbuf_reg[0], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
 
-    obj_type = H5Rget_obj_type1(dataset, H5R_DATASET_REGION, &rbuf_reg[1]);
-    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
-    VERIFY(obj_type, H5G_DATASET, "H5Rget_obj_type1");
-
-    obj_type = H5Rget_obj_type1(dataset, H5R_DATASET_REGION, &rbuf_reg[2]);
-    VERIFY(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
-
-    obj_type = H5Rget_obj_type1(dataset, H5R_DATASET_REGION, &rbuf_reg[3]);
-    VERIFY(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&rbuf_reg[1], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
 
     /* Make sure the referenced objects can be opened */
-    dset2 = H5Rdereference1(dataset, H5R_DATASET_REGION, &rbuf_reg[0]);
-    CHECK(dset2, FAIL, "H5Rdereference1");
+    dset2 = H5Ropen_object((const H5R_ref_t *)&rbuf_reg[0], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dset2, H5I_INVALID_HID, "H5Ropen_object");
 
     ret = H5Dclose(dset2);
     CHECK(ret, FAIL, "H5Dclose");
 
-    dset2 = H5Rdereference1(dataset, H5R_DATASET_REGION, &rbuf_reg[1]);
-    CHECK(dset2, FAIL, "H5Rdereference1");
+    dset2 = H5Ropen_object((const H5R_ref_t *)&rbuf_reg[1], H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dset2, H5I_INVALID_HID, "H5Ropen_object");
 
     ret = H5Dclose(dset2);
     CHECK(ret, FAIL, "H5Dclose");
@@ -1756,13 +2371,424 @@ test_reference_compat(void)
     ret = H5Fclose(fid1);
     CHECK(ret, FAIL, "H5Fclose");
 
+    /* Destroy references */
+    for(i = 0; i < dims1[0]; i++) {
+        ret = H5Rdestroy(&rbuf_obj[i]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+    }
+    for(i = 0; i < dims3[0]; i++) {
+        ret = H5Rdestroy(&rbuf_reg[i]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+    }
+
     /* Free memory buffers */
     HDfree(wbuf_obj);
     HDfree(rbuf_obj);
     HDfree(wbuf_reg);
     HDfree(rbuf_reg);
 }   /* test_reference_compat() */
-#endif /* H5_NO_DEPRECATED_SYMBOLS */
+
+/****************************************************************
+**
+**  test_reference_perf(): Test basic H5R (reference) object reference
+**  performance.
+**
+****************************************************************/
+static void
+test_reference_perf(void)
+{
+    hid_t       fid1;       /* HDF5 File IDs                    */
+    hid_t       dataset,    /* Dataset ID                       */
+                dset2;      /* Dereferenced dataset ID          */
+    hid_t       group;      /* Group ID                         */
+    hid_t       sid1;       /* Dataspace ID                     */
+    hid_t       tid1;       /* Datatype ID                      */
+    hsize_t     dims1[] = {1};
+    hid_t       dapl_id;    /* Dataset access property list     */
+    H5R_ref_t     *wbuf,       /* buffer to write to disk          */
+               *rbuf,       /* buffer read from disk            */
+               *tbuf;       /* temp. buffer read from disk      */
+    H5R_ref_t     *wbuf_reg,    /* buffer to write to disk          */
+               *rbuf_reg;   /* buffer read from disk            */
+    hobj_ref_t *wbuf_deprec,/* deprecated references            */
+               *rbuf_deprec;/* deprecated references            */
+    hdset_reg_ref_t *wbuf_reg_deprec,   /* deprecated references*/
+               *rbuf_reg_deprec;        /* deprecated references*/
+    unsigned   *tu32;       /* Temporary pointer to uint32 data */
+    int         i, j;       /* Counters                         */
+    H5O_type_t  obj_type;   /* Object type                      */
+    herr_t      ret;        /* Generic return value             */
+    double      t1, t2, t;  /* Timers                           */
+
+    /* Output message about test being performed */
+    MESSAGE(5, ("Testing Object Reference Performance\n"));
+
+    /* Allocate write & read buffers */
+    wbuf = (H5R_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(H5R_ref_t)), SPACE1_DIM1);
+    wbuf_deprec = (hobj_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)), SPACE1_DIM1);
+    rbuf = (H5R_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(H5R_ref_t)), SPACE1_DIM1);
+    rbuf_deprec = (hobj_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)), SPACE1_DIM1);
+    tbuf = (H5R_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(H5R_ref_t)), SPACE1_DIM1);
+    wbuf_reg = (H5R_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(H5R_ref_t)), SPACE1_DIM1);
+    rbuf_reg = (H5R_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(H5R_ref_t)), SPACE1_DIM1);
+    wbuf_reg_deprec = (hdset_reg_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(hdset_reg_ref_t)), SPACE1_DIM1);
+    rbuf_reg_deprec = (hdset_reg_ref_t *)HDcalloc(MAX(sizeof(unsigned), sizeof(hdset_reg_ref_t)), SPACE1_DIM1);
+
+    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
+        *tu32++ = (unsigned)i * 3;
+
+    /* Create file */
+    fid1 = H5Fcreate(FILE_REF_OBJ, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fcreate");
+
+    /* Create dataspace for datasets */
+    sid1 = H5Screate_simple(SPACE1_RANK, dims1, NULL);
+    CHECK(sid1, H5I_INVALID_HID, "H5Screate_simple");
+
+    /* Create dataset access property list */
+    dapl_id = H5Pcreate(H5P_DATASET_ACCESS);
+    CHECK(dapl_id, H5I_INVALID_HID, "H5Pcreate");
+
+    /* Create a group */
+    group = H5Gcreate2(fid1, "Group1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(group, H5I_INVALID_HID, "H5Gcreate2");
+
+    /* Create a dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset1", H5T_NATIVE_UINT, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dataset, H5T_NATIVE_UINT, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create another dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset2", H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create a datatype to refer to */
+    tid1 = H5Tcreate(H5T_COMPOUND, sizeof(s1_t));
+    CHECK(tid1, H5I_INVALID_HID, "H5Tcreate");
+
+    /* Insert fields */
+    ret = H5Tinsert(tid1, "a", HOFFSET(s1_t,a), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid1, "b", HOFFSET(s1_t,b), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid1, "c", HOFFSET(s1_t,c), H5T_NATIVE_FLOAT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    /* Save datatype for later */
+    ret = H5Tcommit2(group, "Datatype1", tid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Tcommit2");
+
+    /* Close datatype */
+    ret = H5Tclose(tid1);
+    CHECK(ret, FAIL, "H5Tclose");
+
+    /* Close group */
+    ret = H5Gclose(group);
+    CHECK(ret, FAIL, "H5Gclose");
+
+    /* Create a dataset */
+    dataset = H5Dcreate2(fid1, "Dataset3", H5T_STD_REF, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_CREATE; i++) {
+        t1 = H5_get_time();
+        ret = H5Rcreate_object(fid1, "/Group1/Dataset1", &wbuf[0]);
+        CHECK(ret, FAIL, "H5Rcreate_object");
+        t2 = H5_get_time();
+        t += t2 - t1;
+        ret = H5Rdestroy(&wbuf[0]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+    }
+    HDprintf("--- Object reference create time: %lfs\n", t / MAX_ITER_CREATE);
+
+    /* Create reference to dataset */
+    ret = H5Rcreate_object(fid1, "/Group1/Dataset1", &wbuf[0]);
+    CHECK(ret, FAIL, "H5Rcreate_object");
+    ret = H5Rget_obj_type3((const H5R_ref_t *)&wbuf[0], H5P_DEFAULT, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type3");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type3");
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_WRITE; i++) {
+        t1 = H5_get_time();
+        /* Write selection to disk */
+        ret = H5Dwrite(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
+        CHECK(ret, FAIL, "H5Dwrite");
+        t2 = H5_get_time();
+        t += t2 - t1;
+    }
+    HDprintf("--- Object reference  write time: %lfs\n", t / MAX_ITER_WRITE);
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create a dataset */
+    dataset = H5Dcreate2(fid1, "Dataset4", H5T_STD_REF_OBJ, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_CREATE; i++) {
+        t1 = H5_get_time();
+        ret = H5Rcreate(&wbuf_deprec[0], fid1, "/Group1/Dataset1", H5R_OBJECT1, H5I_INVALID_HID);
+        CHECK(ret, FAIL, "H5Rcreate");
+        t2 = H5_get_time();
+        t += t2 - t1;
+    }
+    HDprintf("--- Deprecated object reference create time: %lfs\n", t / MAX_ITER_CREATE);
+
+    /* Create reference to dataset */
+    ret = H5Rcreate(&wbuf_deprec[0], fid1, "/Group1/Dataset1", H5R_OBJECT1, H5I_INVALID_HID);
+    CHECK(ret, FAIL, "H5Rcreate");
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_WRITE; i++) {
+        t1 = H5_get_time();
+        /* Write selection to disk */
+        ret = H5Dwrite(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf_deprec);
+        CHECK(ret, FAIL, "H5Dwrite");
+        t2 = H5_get_time();
+        t += t2 - t1;
+    }
+    HDprintf("--- Deprecated object reference  write time: %lfs\n", t / MAX_ITER_WRITE);
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create a dataset */
+    dataset = H5Dcreate2(fid1, "Dataset5", H5T_STD_REF, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_CREATE; i++) {
+        t1 = H5_get_time();
+        /* Store first dataset region */
+        ret = H5Rcreate_region(fid1, "/Group1/Dataset1", sid1, &wbuf_reg[0]);
+        CHECK(ret, FAIL, "H5Rcreate_region");
+        t2 = H5_get_time();
+        t += t2 - t1;
+        ret = H5Rdestroy(&wbuf_reg[0]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+    }
+    HDprintf("--- Region reference create time: %lfs\n", t / MAX_ITER_CREATE);
+
+    /* Store first dataset region */
+    ret = H5Rcreate_region(fid1, "/Group1/Dataset1", sid1, &wbuf_reg[0]);
+    CHECK(ret, FAIL, "H5Rcreate_region");
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_WRITE; i++) {
+        t1 = H5_get_time();
+        /* Write selection to disk */
+        ret = H5Dwrite(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf_reg);
+        CHECK(ret, FAIL, "H5Dwrite");
+        t2 = H5_get_time();
+        t += t2 - t1;
+    }
+    HDprintf("--- Region reference  write time: %lfs\n", t / MAX_ITER_WRITE);
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create a dataset */
+    dataset = H5Dcreate2(fid1, "Dataset6", H5T_STD_REF_DSETREG, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dcreate2");
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_CREATE; i++) {
+        t1 = H5_get_time();
+        /* Store first dataset region */
+        ret = H5Rcreate(&wbuf_reg_deprec[0], fid1, "/Group1/Dataset1", H5R_DATASET_REGION1, sid1);
+        CHECK(ret, FAIL, "H5Rcreate");
+        t2 = H5_get_time();
+        t += t2 - t1;
+    }
+    HDprintf("--- Deprecated region reference create time: %lfs\n", t / MAX_ITER_CREATE);
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_WRITE; i++) {
+        t1 = H5_get_time();
+        /* Write selection to disk */
+        ret = H5Dwrite(dataset, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf_reg_deprec);
+        CHECK(ret, FAIL, "H5Dwrite");
+        t2 = H5_get_time();
+        t += t2 - t1;
+    }
+    HDprintf("--- Deprecated region reference  write time: %lfs\n", t / MAX_ITER_WRITE);
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close disk dataspace */
+    ret = H5Sclose(sid1);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Re-open the file */
+    fid1 = H5Fopen(FILE_REF_OBJ, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK(fid1, H5I_INVALID_HID, "H5Fopen");
+
+    /* Open the dataset */
+    dataset = H5Dopen2(fid1, "/Dataset3", H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dopen2");
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_READ; i++) {
+        t1 = H5_get_time();
+        /* Read selection from disk */
+        ret = H5Dread(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf);
+        CHECK(ret, FAIL, "H5Dread");
+        t2 = H5_get_time();
+        t += t2 - t1;
+        ret = H5Rdestroy(&rbuf[0]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+    }
+    HDprintf("--- Object reference read time: %lfs\n", t / MAX_ITER_READ);
+
+    /* Read selection from disk */
+    ret = H5Dread(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /* Open dataset object */
+    dset2 = H5Ropen_object((const H5R_ref_t *)&rbuf[0], H5P_DEFAULT, dapl_id);
+    CHECK(dset2, H5I_INVALID_HID, "H5Ropen_object");
+
+    /* Check information in referenced dataset */
+    sid1 = H5Dget_space(dset2);
+    CHECK(sid1, H5I_INVALID_HID, "H5Dget_space");
+
+    ret = (int)H5Sget_simple_extent_npoints(sid1);
+    VERIFY(ret, dims1[0], "H5Sget_simple_extent_npoints");
+
+    /* Read from disk */
+    ret = H5Dread(dset2, H5T_NATIVE_UINT, H5S_ALL, H5S_ALL, H5P_DEFAULT, tbuf);
+    CHECK(ret, FAIL, "H5Dread");
+
+    for(tu32 = (unsigned *)tbuf, i = 0; i < (int)dims1[0]; i++, tu32++)
+        VERIFY(*tu32, (uint32_t)(i*3), "Data");
+
+    /* Close dereferenced Dataset */
+    ret = H5Dclose(dset2);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Open the dataset */
+    dataset = H5Dopen2(fid1, "/Dataset4", H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dopen2");
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_READ; i++) {
+        t1 = H5_get_time();
+        /* Read selection from disk */
+        ret = H5Dread(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf_deprec);
+        CHECK(ret, FAIL, "H5Dread");
+        t2 = H5_get_time();
+        t += t2 - t1;
+    }
+    HDprintf("--- Deprecated object reference read time: %lfs\n", t / MAX_ITER_READ);
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Open the dataset */
+    dataset = H5Dopen2(fid1, "/Dataset5", H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dopen2");
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_READ; i++) {
+        t1 = H5_get_time();
+        /* Read selection from disk */
+        ret = H5Dread(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf_reg);
+        CHECK(ret, FAIL, "H5Dread");
+        t2 = H5_get_time();
+        t += t2 - t1;
+        ret = H5Rdestroy(&rbuf_reg[0]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+    }
+    HDprintf("--- Region reference read time: %lfs\n", t / MAX_ITER_READ);
+
+    /* Read selection from disk */
+    ret = H5Dread(dataset, H5T_STD_REF, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf_reg);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Open the dataset */
+    dataset = H5Dopen2(fid1, "/Dataset6", H5P_DEFAULT);
+    CHECK(dataset, H5I_INVALID_HID, "H5Dopen2");
+
+    t = 0;
+    for(i = 0; i < MAX_ITER_READ; i++) {
+        t1 = H5_get_time();
+        /* Read selection from disk */
+        ret = H5Dread(dataset, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf_reg_deprec);
+        CHECK(ret, FAIL, "H5Dread");
+        t2 = H5_get_time();
+        t += t2 - t1;
+    }
+    HDprintf("--- Deprecated region reference read time: %lfs\n", t / MAX_ITER_READ);
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close dataset access property list */
+    ret = H5Pclose(dapl_id);
+    CHECK(ret, FAIL, "H5Pclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Destroy references */
+    for(j = 0; j < (int)dims1[0]; j++) {
+        ret = H5Rdestroy(&wbuf[j]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+        ret = H5Rdestroy(&wbuf_reg[j]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+        ret = H5Rdestroy(&rbuf[j]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+        ret = H5Rdestroy(&rbuf_reg[j]);
+        CHECK(ret, FAIL, "H5Rdestroy");
+    }
+
+    /* Free memory buffers */
+    HDfree(wbuf);
+    HDfree(rbuf);
+    HDfree(wbuf_reg);
+    HDfree(rbuf_reg);
+    HDfree(wbuf_deprec);
+    HDfree(rbuf_deprec);
+    HDfree(wbuf_reg_deprec);
+    HDfree(rbuf_reg_deprec);
+    HDfree(tbuf);
+}   /* test_reference_perf() */
 
 /****************************************************************
 **
@@ -1794,11 +2820,13 @@ test_reference(void)
         } /* end high bound */
     } /* end low bound */
 
-    test_reference_obj_deleted(); /* Test H5R object reference code for deleted objects */
-    test_reference_group();     /* Test operations on dereferenced groups */
-#ifndef H5_NO_DEPRECATED_SYMBOLS
-    test_reference_compat();    /* Test operations with old API routines */
-#endif /* H5_NO_DEPRECATED_SYMBOLS */
+    test_reference_obj_deleted();   /* Test H5R object reference code for deleted objects */
+    test_reference_group();         /* Test operations on dereferenced groups */
+    test_reference_attr();          /* Test attribute references */
+    test_reference_external();      /* Test external references */
+    test_reference_compat_conv();   /* Test operations with old types */
+
+    test_reference_perf();
 
 }   /* test_reference() */
 
@@ -1820,8 +2848,14 @@ test_reference(void)
 void
 cleanup_reference(void)
 {
-    remove(FILE1);
-    remove(FILE2);
-    remove(FILE3);
+    HDremove(FILE_REF_PARAM);
+    HDremove(FILE_REF_OBJ);
+    HDremove(FILE_REF_REG);
+    HDremove(FILE_REF_REG_1D);
+    HDremove(FILE_REF_OBJ_DEL);
+    HDremove(FILE_REF_GRP);
+    HDremove(FILE_REF_ATTR);
+    HDremove(FILE_REF_EXT1);
+    HDremove(FILE_REF_EXT2);
+    HDremove(FILE_REF_COMPAT);
 }
-
diff --git a/test/trefer_deprec.c b/test/trefer_deprec.c
new file mode 100644
index 0000000..949f41b
--- /dev/null
+++ b/test/trefer_deprec.c
@@ -0,0 +1,1827 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the COPYING file, which can be found at the root of the source code       *
+ * distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.  *
+ * If you do not have access to either file, you may request a copy from     *
+ * help@hdfgroup.org.                                                        *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/***********************************************************
+*
+* Test program:     trefer_deprec
+*
+* Test the Reference functionality
+*
+*************************************************************/
+
+#include "testhdf5.h"
+
+#define FILE1    "trefer1.h5"
+#define FILE2    "trefer2.h5"
+#define FILE3    "trefer3.h5"
+
+/* 1-D dataset with fixed dimensions */
+#define SPACE1_RANK    1
+#define SPACE1_DIM1    4
+
+/* 2-D dataset with fixed dimensions */
+#define SPACE2_RANK    2
+#define SPACE2_DIM1    10
+#define SPACE2_DIM2    10
+
+/* Larger 1-D dataset with fixed dimensions */
+#define SPACE3_RANK    1
+#define SPACE3_DIM1    100
+
+/* Element selection information */
+#define POINT1_NPOINTS 10
+
+/* Compound datatype */
+typedef struct s1_t {
+    unsigned int a;
+    unsigned int b;
+    float c;
+} s1_t;
+
+#define GROUPNAME       "/group"
+#define GROUPNAME2      "group2"
+#define GROUPNAME3      "group3"
+#define DSETNAME        "/dset"
+#define DSETNAME2       "dset2"
+#define NAME_SIZE       16
+
+
+/****************************************************************
+**
+**  test_reference_params(): Test basic H5R (reference) parameters
+**                           for correct processing
+**
+****************************************************************/
+static void
+test_reference_params(void)
+{
+    hid_t       fid1;       /* HDF5 File IDs        */
+    hid_t       dataset,    /* Dataset ID           */
+                dset2;      /* Dereferenced dataset ID */
+    hid_t       group;      /* Group ID             */
+    hid_t       sid1;       /* Dataspace ID         */
+    hid_t       tid1;       /* Datatype ID          */
+    hid_t       dapl_id;    /* Dataset access property list */
+    hsize_t     dims1[] = {SPACE1_DIM1};
+    hobj_ref_t *wbuf,       /* buffer to write to disk */
+               *rbuf,       /* buffer read from disk */
+               *tbuf;       /* temp. buffer read from disk */
+    unsigned   *tu32;       /* Temporary pointer to uint32 data */
+    int         i;          /* counting variables */
+    const char *write_comment = "Foo!"; /* Comments for group */
+    hid_t    ret_id;        /* Generic hid_t return value    */
+    ssize_t     name_size;  /* Size of reference name */
+    herr_t      ret;        /* Generic return value     */
+
+    /* Output message about test being performed */
+    MESSAGE(5, ("Testing Reference Parameters\n"));
+
+    /* Allocate write & read buffers */
+    wbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
+    rbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
+    tbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
+
+    /* Create file */
+    fid1 = H5Fcreate(FILE1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid1, FAIL, "H5Fcreate");
+
+    /* Create dataspace for datasets */
+    sid1 = H5Screate_simple(SPACE1_RANK, dims1, NULL);
+    CHECK(sid1, FAIL, "H5Screate_simple");
+
+    /* Create dataset access property list */
+    dapl_id = H5Pcreate(H5P_DATASET_ACCESS);
+    CHECK(dapl_id, FAIL, "H5Pcreate");
+
+    /* Create a group */
+    group = H5Gcreate2(fid1, "Group1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(group, FAIL, "H5Gcreate2");
+
+    /* Set group's comment */
+    ret = H5Oset_comment(group, write_comment);
+    CHECK(ret, FAIL, "H5Oset_comment");
+
+    /* Create a dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset1", H5T_NATIVE_UINT, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
+        *tu32++ = (unsigned)i * 3;
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dataset, H5T_NATIVE_UINT, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create another dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset2", H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create a datatype to refer to */
+    tid1 = H5Tcreate(H5T_COMPOUND, sizeof(s1_t));
+    CHECK(tid1, FAIL, "H5Tcreate");
+
+    /* Insert fields */
+    ret = H5Tinsert(tid1, "a", HOFFSET(s1_t,a), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid1, "b", HOFFSET(s1_t,b), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid1, "c", HOFFSET(s1_t,c), H5T_NATIVE_FLOAT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    /* Save datatype for later */
+    ret = H5Tcommit2(group, "Datatype1", tid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Tcommit2");
+
+    /* Close datatype */
+    ret = H5Tclose(tid1);
+    CHECK(ret, FAIL, "H5Tclose");
+
+    /* Close group */
+    ret = H5Gclose(group);
+    CHECK(ret, FAIL, "H5Gclose");
+
+    /* Create a dataset */
+    dataset = H5Dcreate2(fid1, "Dataset3", H5T_STD_REF_OBJ, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Dcreate2");
+
+    /* Test parameters to H5Rcreate */
+    ret = H5Rcreate(NULL, fid1, "/Group1/Dataset1", H5R_OBJECT, (hid_t)-1);
+    VERIFY(ret, FAIL, "H5Rcreate ref");
+    ret = H5Rcreate(&wbuf[0], (hid_t)-1, "/Group1/Dataset1", H5R_OBJECT, (hid_t)-1);
+    VERIFY(ret, FAIL, "H5Rcreate loc_id");
+    ret = H5Rcreate(&wbuf[0], fid1, NULL, H5R_OBJECT, (hid_t)-1);
+    VERIFY(ret, FAIL, "H5Rcreate name");
+    ret = H5Rcreate(&wbuf[0], fid1, "", H5R_OBJECT, (hid_t)-1);
+    VERIFY(ret, FAIL, "H5Rcreate null name");
+    ret = H5Rcreate(&wbuf[0], fid1, "/Group1/Dataset1", H5R_MAXTYPE, (hid_t)-1);
+    VERIFY(ret, FAIL, "H5Rcreate type");
+    ret = H5Rcreate(&wbuf[0], fid1, "/Group1/Dataset1", H5R_DATASET_REGION, (hid_t)-1);
+    VERIFY(ret, FAIL, "H5Rcreate region space");
+    ret = H5Rcreate(&wbuf[0], fid1, "/Group1/Dataset1", H5R_MAXTYPE, (hid_t)0);
+    VERIFY(ret, FAIL, "H5Rcreate space");
+
+    /* Test parameters to H5Rdereference */
+    dset2 = H5Rdereference2((hid_t)-1, H5P_DEFAULT, H5R_OBJECT, &rbuf[0]);
+    VERIFY(dset2, FAIL, "H5Rdereference2 loc_id");
+    dset2 = H5Rdereference2(dataset, (hid_t)-1, H5R_OBJECT, &rbuf[0]);
+    VERIFY(dset2, FAIL, "H5Rdereference2 oapl_id");
+    dset2 = H5Rdereference2(dataset, dapl_id, H5R_OBJECT, NULL);
+    VERIFY(dset2, FAIL, "H5Rdereference2 ref");
+    dset2 = H5Rdereference2(dataset, dapl_id, H5R_MAXTYPE, &rbuf[0]);
+    VERIFY(dset2, FAIL, "H5Rdereference2 type");
+
+    /* Test parameters to H5Rget_obj_type2 */
+    ret = H5Rget_obj_type2((hid_t)-1, H5R_OBJECT, &rbuf[0], NULL);
+    VERIFY(ret, FAIL, "H5Rget_obj_type2 loc_id");
+    ret = H5Rget_obj_type2(fid1, H5R_OBJECT, NULL, NULL);
+    VERIFY(ret, FAIL, "H5Rget_obj_type2 ref");
+    ret = H5Rget_obj_type2(fid1, H5R_MAXTYPE, &rbuf[0], NULL);
+    VERIFY(ret, FAIL, "H5Rget_obj_type2 type");
+
+    /* Test parameters to H5Rget_name */
+    name_size = H5Rget_name((hid_t)-1, H5R_DATASET_REGION, &rbuf[0], NULL, 0);
+    VERIFY(name_size, FAIL, "H5Rget_name loc_id");
+    name_size = H5Rget_name(fid1, H5R_DATASET_REGION, NULL, NULL, 0);
+    VERIFY(name_size, FAIL, "H5Rget_name ref");
+    name_size = H5Rget_name(fid1, H5R_MAXTYPE, &rbuf[0], NULL, 0);
+    VERIFY(name_size, FAIL, "H5Rget_name type");
+
+    /* Test parameters to H5Rget_region */
+    ret_id = H5Rget_region((hid_t)-1, H5R_OBJECT, &rbuf[0]);
+    VERIFY(ret_id, FAIL, "H5Rget_region loc_id");
+    ret_id = H5Rget_region(fid1, H5R_OBJECT, NULL);
+    VERIFY(ret_id, FAIL, "H5Rget_region ref");
+    ret_id = H5Rget_region(fid1, H5R_OBJECT, &rbuf[0]);
+    VERIFY(ret_id, FAIL, "H5Rget_region type");
+
+    /* Close disk dataspace */
+    ret = H5Sclose(sid1);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close dataset access property list */
+    ret = H5Pclose(dapl_id);
+    CHECK(ret, FAIL, "H5Pclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Free memory buffers */
+    HDfree(wbuf);
+    HDfree(rbuf);
+    HDfree(tbuf);
+}   /* test_reference_obj() */
+
+/****************************************************************
+**
+**  test_reference_obj(): Test basic H5R (reference) object reference code.
+**      Tests references to various kinds of objects
+**
+****************************************************************/
+static void
+test_reference_obj(void)
+{
+    hid_t        fid1;        /* HDF5 File IDs        */
+    hid_t        dataset,    /* Dataset ID            */
+                        dset2;      /* Dereferenced dataset ID */
+    hid_t        group;      /* Group ID             */
+    hid_t        sid1;       /* Dataspace ID            */
+    hid_t        tid1;       /* Datatype ID            */
+    hsize_t        dims1[] = {SPACE1_DIM1};
+    hid_t               dapl_id;    /* Dataset access property list */
+    hobj_ref_t          *wbuf,      /* buffer to write to disk */
+                        *rbuf,      /* buffer read from disk */
+                        *tbuf;      /* temp. buffer read from disk */
+    hobj_ref_t  nvrbuf[3]={0,101,1000000000}; /* buffer with non-valid refs */
+    unsigned            *tu32;      /* Temporary pointer to uint32 data */
+    int                 i, j;       /* counting variables */
+    const char *write_comment="Foo!"; /* Comments for group */
+    char read_comment[10];
+    H5O_type_t          obj_type;   /* Object type */
+    ssize_t             size;       /* Comment length */
+    herr_t        ret;        /* Generic return value        */
+
+    /* Output message about test being performed */
+    MESSAGE(5, ("Testing Object Reference Functions\n"));
+
+    /* Allocate write & read buffers */
+    wbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
+    rbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
+    tbuf = (hobj_ref_t *)HDmalloc(MAX(sizeof(unsigned), sizeof(hobj_ref_t)) * SPACE1_DIM1);
+
+    /* Create file */
+    fid1 = H5Fcreate(FILE1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid1, FAIL, "H5Fcreate");
+
+    /* Create dataspace for datasets */
+    sid1 = H5Screate_simple(SPACE1_RANK, dims1, NULL);
+    CHECK(sid1, FAIL, "H5Screate_simple");
+
+    /* Create dataset access property list */
+    dapl_id = H5Pcreate(H5P_DATASET_ACCESS);
+    CHECK(dapl_id, FAIL, "H5Pcreate");
+
+    /* Create a group */
+    group = H5Gcreate2(fid1, "Group1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(group, FAIL, "H5Gcreate2");
+
+    /* Set group's comment */
+    ret = H5Oset_comment(group, write_comment);
+    CHECK(ret, FAIL, "H5Oset_comment");
+
+    /* Create a dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset1", H5T_NATIVE_UINT, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    for(tu32 = (unsigned *)wbuf, i = 0; i < SPACE1_DIM1; i++)
+        *tu32++ = (unsigned)i * 3;
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dataset, H5T_NATIVE_UINT, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create another dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset2", H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create a datatype to refer to */
+    tid1 = H5Tcreate(H5T_COMPOUND, sizeof(s1_t));
+    CHECK(tid1, FAIL, "H5Tcreate");
+
+    /* Insert fields */
+    ret = H5Tinsert(tid1, "a", HOFFSET(s1_t,a), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid1, "b", HOFFSET(s1_t,b), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid1, "c", HOFFSET(s1_t,c), H5T_NATIVE_FLOAT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    /* Save datatype for later */
+    ret = H5Tcommit2(group, "Datatype1", tid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Tcommit2");
+
+    /* Close datatype */
+    ret = H5Tclose(tid1);
+    CHECK(ret, FAIL, "H5Tclose");
+
+    /* Close group */
+    ret = H5Gclose(group);
+    CHECK(ret, FAIL, "H5Gclose");
+
+    /* Create a dataset */
+    dataset = H5Dcreate2(fid1, "Dataset3", H5T_STD_REF_OBJ, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    /* Create reference to dataset */
+    ret = H5Rcreate(&wbuf[0], fid1, "/Group1/Dataset1", H5R_OBJECT, (hid_t)-1);
+    CHECK(ret, FAIL, "H5Rcreate");
+    ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &wbuf[0], &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type2");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+
+    /* Create reference to dataset */
+    ret = H5Rcreate(&wbuf[1], fid1, "/Group1/Dataset2", H5R_OBJECT, (hid_t)-1);
+    CHECK(ret, FAIL, "H5Rcreate");
+    ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &wbuf[1], &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type2");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+
+    /* Create reference to group */
+    ret = H5Rcreate(&wbuf[2], fid1, "/Group1", H5R_OBJECT, (hid_t)-1);
+    CHECK(ret, FAIL, "H5Rcreate");
+    ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &wbuf[2], &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type2");
+    VERIFY(obj_type, H5O_TYPE_GROUP, "H5Rget_obj_type2");
+
+    /* Create reference to named datatype */
+    ret = H5Rcreate(&wbuf[3], fid1, "/Group1/Datatype1", H5R_OBJECT, (hid_t)-1);
+    CHECK(ret, FAIL, "H5Rcreate");
+    ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &wbuf[3], &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type2");
+    VERIFY(obj_type, H5O_TYPE_NAMED_DATATYPE, "H5Rget_obj_type2");
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close disk dataspace */
+    ret = H5Sclose(sid1);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Re-open the file */
+    fid1 = H5Fopen(FILE1, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK(fid1, FAIL, "H5Fopen");
+
+    /* Open the dataset */
+    dataset = H5Dopen2(fid1, "/Dataset3", H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dopen2");
+
+    /* Read selection from disk */
+    ret = H5Dread(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /* Open dataset object */
+    dset2 = H5Rdereference2(dataset, dapl_id, H5R_OBJECT, &rbuf[0]);
+    CHECK(dset2, FAIL, "H5Rdereference2");
+
+    /* Check information in referenced dataset */
+    sid1 = H5Dget_space(dset2);
+    CHECK(sid1, FAIL, "H5Dget_space");
+
+    ret = (int)H5Sget_simple_extent_npoints(sid1);
+    VERIFY(ret, 4, "H5Sget_simple_extent_npoints");
+
+    /* Read from disk */
+    ret = H5Dread(dset2, H5T_NATIVE_UINT, H5S_ALL, H5S_ALL, H5P_DEFAULT, tbuf);
+    CHECK(ret, FAIL, "H5Dread");
+
+    for(tu32 = (unsigned *)tbuf, i = 0; i < SPACE1_DIM1; i++, tu32++)
+        VERIFY(*tu32, (uint32_t)(i*3), "Data");
+
+    /* Close dereferenced Dataset */
+    ret = H5Dclose(dset2);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Open group object.  GAPL isn't supported yet.  But it's harmless to pass in */
+    group = H5Rdereference2(dataset, H5P_DEFAULT, H5R_OBJECT, &rbuf[2]);
+    CHECK(group, FAIL, "H5Rdereference2");
+
+    /* Get group's comment */
+    size = H5Oget_comment(group, read_comment, (size_t)10);
+    CHECK(size, FAIL, "H5Oget_comment");
+
+    /* Check for correct comment value */
+    if(HDstrcmp(write_comment, read_comment) != 0)
+        TestErrPrintf("Error! Incorrect group comment, wanted: %s, got: %s\n",write_comment,read_comment);
+
+    /* Close group */
+    ret = H5Gclose(group);
+    CHECK(ret, FAIL, "H5Gclose");
+
+    /* Open datatype object. TAPL isn't supported yet.  But it's harmless to pass in */
+    tid1 = H5Rdereference2(dataset, H5P_DEFAULT, H5R_OBJECT, &rbuf[3]);
+    CHECK(tid1, FAIL, "H5Rdereference2");
+
+    /* Verify correct datatype */
+    {
+        H5T_class_t tclass;
+
+        tclass = H5Tget_class(tid1);
+        VERIFY(tclass, H5T_COMPOUND, "H5Tget_class");
+
+        ret= H5Tget_nmembers(tid1);
+        VERIFY(ret, 3, "H5Tget_nmembers");
+    }
+
+    /* Attempting to retrieve type of object using non-valid refs */
+    for(j = 0; j < 3; j++) {
+        H5E_BEGIN_TRY {
+            ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &nvrbuf[j], &obj_type);
+        } H5E_END_TRY;
+        VERIFY(ret, FAIL, "H5Rget_obj_type2");
+    } /* end for */
+
+    /* Close datatype */
+    ret = H5Tclose(tid1);
+    CHECK(ret, FAIL, "H5Tclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close dataset access property list */
+    ret = H5Pclose(dapl_id);
+    CHECK(ret, FAIL, "H5Pclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Free memory buffers */
+    HDfree(wbuf);
+    HDfree(rbuf);
+    HDfree(tbuf);
+}   /* test_reference_obj() */
+
+/****************************************************************
+**
+**  test_reference_region(): Test basic H5R (reference) object reference code.
+**      Tests references to various kinds of objects
+**
+**  Note: The libver_low/libver_high parameters are added to create the file
+**        with the low and high bounds setting in fapl.  
+**        Please see the RFC for "H5Sencode/H5Sdecode Format Change".
+**
+****************************************************************/
+static void
+test_reference_region(H5F_libver_t libver_low, H5F_libver_t libver_high)
+{
+    hid_t fid1;         /* HDF5 File IDs */
+    hid_t fapl = -1;    /* File access property list */
+    hid_t dset1,        /* Dataset ID */
+          dset2;        /* Dereferenced dataset ID */
+    hid_t sid1,         /* Dataspace ID #1 */
+          sid2;         /* Dataspace ID #2 */
+    hid_t dapl_id;      /* Dataset access property list */
+    hsize_t dims1[] = {SPACE1_DIM1},
+            dims2[] = {SPACE2_DIM1, SPACE2_DIM2};
+    hsize_t start[SPACE2_RANK];     /* Starting location of hyperslab */
+    hsize_t stride[SPACE2_RANK];    /* Stride of hyperslab */
+    hsize_t count[SPACE2_RANK];     /* Element count of hyperslab */
+    hsize_t block[SPACE2_RANK];     /* Block size of hyperslab */
+    hsize_t coord1[POINT1_NPOINTS][SPACE2_RANK]; /* Coordinates for point selection */
+    hsize_t *coords;            /* Coordinate buffer */
+    hsize_t low[SPACE2_RANK];   /* Selection bounds */
+    hsize_t high[SPACE2_RANK];  /* Selection bounds */
+    hdset_reg_ref_t *wbuf,      /* buffer to write to disk */
+                    *rbuf;      /* buffer read from disk */
+    hdset_reg_ref_t  nvrbuf[3]={{0},{101},{255}}; /* buffer with non-valid refs */
+    uint8_t *dwbuf,             /* Buffer for writing numeric data to disk */
+            *drbuf;             /* Buffer for reading numeric data from disk */
+    uint8_t *tu8;               /* Temporary pointer to uint8 data */
+    H5O_type_t obj_type;        /* Type of object */
+    int i, j;                   /* counting variables */
+    hssize_t hssize_ret;        /* hssize_t return value */
+    htri_t tri_ret;             /* htri_t return value */
+    herr_t ret;                 /* Generic return value     */
+    hdset_reg_ref_t undef_reg[1];   /* test for undefined reference */
+    hid_t dset_NA;              /* Dataset id for undefined reference */
+    hid_t space_NA;             /* Dataspace id for undefined reference */
+    hsize_t dims_NA[1] = {1};   /* Dims array for undefined reference */
+    hdset_reg_ref_t wdata_NA[1],    /* Write buffer */
+                    rdata_NA[1];    /* Read buffer */
+
+    /* Output message about test being performed */
+    MESSAGE(5, ("Testing Dataset Region Reference Functions\n"));
+
+    /* Allocate write & read buffers */
+    wbuf = (hdset_reg_ref_t *)HDcalloc(sizeof(hdset_reg_ref_t), (size_t)SPACE1_DIM1);
+    rbuf = (hdset_reg_ref_t *)HDmalloc(sizeof(hdset_reg_ref_t) * SPACE1_DIM1);
+    dwbuf = (uint8_t *)HDmalloc(sizeof(uint8_t) * SPACE2_DIM1 * SPACE2_DIM2);
+    drbuf = (uint8_t *)HDcalloc(sizeof(uint8_t), (size_t)(SPACE2_DIM1 * SPACE2_DIM2));
+
+    /* Create file access property list */
+    fapl = H5Pcreate(H5P_FILE_ACCESS);
+    CHECK(fapl, FAIL, "H5Pcreate");
+
+    /* Set the low/high version bounds in fapl */
+    ret = H5Pset_libver_bounds(fapl, libver_low, libver_high);
+    CHECK(ret, FAIL, "H5Pset_libver_bounds");
+
+    /* Create file with the fapl */
+    fid1 = H5Fcreate(FILE2, H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
+    CHECK(fid1, FAIL, "H5Fcreate");
+
+    /* Create dataspace for datasets */
+    sid2 = H5Screate_simple(SPACE2_RANK, dims2, NULL);
+    CHECK(sid2, FAIL, "H5Screate_simple");
+
+    /* Create dataset access property list */
+    dapl_id = H5Pcreate(H5P_DATASET_ACCESS);
+    CHECK(dapl_id, FAIL, "H5Pcreate");
+
+    /* Create a dataset */
+    dset2 = H5Dcreate2(fid1, "Dataset2", H5T_STD_U8LE, sid2, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dset2, FAIL, "H5Dcreate2");
+
+    for(tu8 = dwbuf, i = 0; i < (SPACE2_DIM1 * SPACE2_DIM2); i++)
+        *tu8++ = (uint8_t)(i * 3);
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dset2, H5T_STD_U8LE, H5S_ALL, H5S_ALL, H5P_DEFAULT, dwbuf);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close Dataset */
+    ret = H5Dclose(dset2);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create dataspace for the reference dataset */
+    sid1 = H5Screate_simple(SPACE1_RANK, dims1, NULL);
+    CHECK(sid1, FAIL, "H5Screate_simple");
+
+    /* Create a dataset */
+    dset1 = H5Dcreate2(fid1, "Dataset1", H5T_STD_REF_DSETREG, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dset1, FAIL, "H5Dcreate2");
+
+    /* Create references */
+
+    /* Select 6x6 hyperslab for first reference */
+    start[0] = 2; start[1] = 2;
+    stride[0] = 1; stride[1] = 1;
+    count[0] = 1; count[1] = 1;
+    block[0] = 6; block[1] = 6;
+    ret = H5Sselect_hyperslab(sid2, H5S_SELECT_SET, start, stride, count, block);
+    CHECK(ret, FAIL, "H5Sselect_hyperslab");
+
+    ret = (int)H5Sget_select_npoints(sid2);
+    VERIFY(ret, 36, "H5Sget_select_npoints");
+
+    /* Store first dataset region */
+    ret = H5Rcreate(&wbuf[0], fid1, "/Dataset2", H5R_DATASET_REGION, sid2);
+    CHECK(ret, FAIL, "H5Rcreate");
+    ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &wbuf[0], &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type2");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+
+    /* Select sequence of ten points for second reference */
+    coord1[0][0] = 6; coord1[0][1] = 9;
+    coord1[1][0] = 2; coord1[1][1] = 2;
+    coord1[2][0] = 8; coord1[2][1] = 4;
+    coord1[3][0] = 1; coord1[3][1] = 6;
+    coord1[4][0] = 2; coord1[4][1] = 8;
+    coord1[5][0] = 3; coord1[5][1] = 2;
+    coord1[6][0] = 0; coord1[6][1] = 4;
+    coord1[7][0] = 9; coord1[7][1] = 0;
+    coord1[8][0] = 7; coord1[8][1] = 1;
+    coord1[9][0] = 3; coord1[9][1] = 3;
+    ret = H5Sselect_elements(sid2, H5S_SELECT_SET, (size_t)POINT1_NPOINTS, (const hsize_t *)coord1);
+    CHECK(ret, FAIL, "H5Sselect_elements");
+
+    ret = (int)H5Sget_select_npoints(sid2);
+    VERIFY(ret, 10, "H5Sget_select_npoints");
+
+    /* Store second dataset region */
+    ret = H5Rcreate(&wbuf[1], fid1, "/Dataset2", H5R_DATASET_REGION, sid2);
+    CHECK(ret, FAIL, "H5Rcreate");
+
+    /* Select unlimited hyperslab for third reference */
+    start[0] = 1; start[1] = 8;
+    stride[0] = 4; stride[1] = 1;
+    count[0] = H5S_UNLIMITED; count[1] = 1;
+    block[0] = 2; block[1] = 2;
+    ret = H5Sselect_hyperslab(sid2, H5S_SELECT_SET, start, stride, count, block);
+    CHECK(ret, FAIL, "H5Sselect_hyperslab");
+
+    hssize_ret = H5Sget_select_npoints(sid2);
+    VERIFY(hssize_ret, (hssize_t)H5S_UNLIMITED, "H5Sget_select_npoints");
+
+    /* Store third dataset region */
+    H5E_BEGIN_TRY {
+        ret = H5Rcreate(&wbuf[2], fid1, "/Dataset2", H5R_DATASET_REGION, sid2);
+    } H5E_END_TRY;
+
+    if(libver_high < H5F_LIBVER_V110)
+        VERIFY(ret, FAIL, "H5Rcreate");
+    else
+        CHECK(ret, FAIL, "H5Rcreate");
+
+    ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &wbuf[0], &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type2");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dset1, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /*
+     * Store a dataset region reference which will not get written to disk
+     */
+
+    /* Create reference to an element in dset1 */
+    ret = H5Sselect_elements(sid2, H5S_SELECT_SET, (size_t)1, (const hsize_t *)coord1);
+    CHECK(ret, FAIL, "H5Sselect_elements");
+    ret = H5Rcreate(&wdata_NA[0], fid1, "/Dataset1", H5R_DATASET_REGION, sid2);
+    CHECK(ret, FAIL, "H5Rcreate");
+
+    /* Create the dataspace of the region references */
+    space_NA = H5Screate_simple(1, dims_NA, NULL);
+    CHECK(space_NA, FAIL, "H5Screate_simple");
+
+    /* Create the dataset and write the region references to it */
+    dset_NA = H5Dcreate2(fid1, "DS_NA", H5T_STD_REF_DSETREG, space_NA, H5P_DEFAULT,
+                H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dset_NA, FAIL, "H5Dcreate");
+
+    /* Close and release resources for undefined region reference tests */
+    ret = H5Dclose(dset_NA);
+    CHECK(ret, FAIL, "H5Dclose");
+    ret = H5Sclose(space_NA);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close disk dataspace */
+    ret = H5Sclose(sid1);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dset1);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close uint8 dataset dataspace */
+    ret = H5Sclose(sid2);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Re-open the file */
+    fid1 = H5Fopen(FILE2, H5F_ACC_RDWR, fapl);
+    CHECK(fid1, FAIL, "H5Fopen");
+
+    /*
+     * Start the test of an undefined reference
+     */
+
+    /* Open the dataset of the undefined references */
+    dset_NA = H5Dopen2(fid1, "DS_NA", H5P_DEFAULT);
+    CHECK(dset_NA, FAIL, "H5Dopen2");
+
+    /* Read the data */
+    ret = H5Dread(dset_NA, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, rdata_NA);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /*
+     * Dereference an undefined reference (should fail)
+     */
+    H5E_BEGIN_TRY {
+      dset2 = H5Rdereference2(dset_NA, H5P_DEFAULT, H5R_DATASET_REGION, &rdata_NA[0]);
+    } H5E_END_TRY;
+    VERIFY(dset2, FAIL, "H5Rdereference2");
+
+    /* Close and release resources. */
+    ret = H5Dclose(dset_NA);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* This close should fail since H5Rdereference2 never created
+     * the id of the referenced object. */
+    H5E_BEGIN_TRY {
+      ret = H5Dclose(dset2);
+    } H5E_END_TRY;
+    VERIFY(ret, FAIL, "H5Dclose");
+
+    /*
+     * End the test of an undefined reference
+     */
+
+    /* Open the dataset */
+    dset1 = H5Dopen2(fid1, "/Dataset1", H5P_DEFAULT);
+    CHECK(dset1, FAIL, "H5Dopen2");
+
+    /* Read selection from disk */
+    ret = H5Dread(dset1, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /* Try to read an unaddressed dataset */
+    dset2 = H5Rdereference2(dset1, dapl_id, H5R_DATASET_REGION, undef_reg);
+    VERIFY(dset2, FAIL, "H5Rdereference2 haddr_undef");
+
+    /* Try to open objects */
+    dset2 = H5Rdereference2(dset1, dapl_id, H5R_DATASET_REGION, &rbuf[0]);
+    CHECK(dset2, FAIL, "H5Rdereference2");
+
+    /* Check what H5Rget_obj_type2 function returns */
+    ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &rbuf[0], &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type2");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+
+    /* Check information in referenced dataset */
+    sid1 = H5Dget_space(dset2);
+    CHECK(sid1, FAIL, "H5Dget_space");
+
+    ret = (int)H5Sget_simple_extent_npoints(sid1);
+    VERIFY(ret, 100, "H5Sget_simple_extent_npoints");
+
+    /* Read from disk */
+    ret = H5Dread(dset2, H5T_STD_U8LE, H5S_ALL, H5S_ALL, H5P_DEFAULT, drbuf);
+    CHECK(ret, FAIL, "H5Dread");
+
+    for(tu8 = (uint8_t *)drbuf, i = 0; i < (SPACE2_DIM1 * SPACE2_DIM2); i++, tu8++)
+        VERIFY(*tu8, (uint8_t)(i * 3), "Data");
+
+    /* Get the hyperslab selection */
+    sid2 = H5Rget_region(dset1, H5R_DATASET_REGION, &rbuf[0]);
+    CHECK(sid2, FAIL, "H5Rget_region");
+
+    /* Verify correct hyperslab selected */
+    ret = (int)H5Sget_select_npoints(sid2);
+    VERIFY(ret, 36, "H5Sget_select_npoints");
+    ret = (int)H5Sget_select_hyper_nblocks(sid2);
+    VERIFY(ret, 1, "H5Sget_select_hyper_nblocks");
+    coords = (hsize_t *)HDmalloc((size_t)ret * SPACE2_RANK * sizeof(hsize_t) * 2); /* allocate space for the hyperslab blocks */
+    ret = H5Sget_select_hyper_blocklist(sid2, (hsize_t)0, (hsize_t)ret, coords);
+    CHECK(ret, FAIL, "H5Sget_select_hyper_blocklist");
+    VERIFY(coords[0], 2, "Hyperslab Coordinates");
+    VERIFY(coords[1], 2, "Hyperslab Coordinates");
+    VERIFY(coords[2], 7, "Hyperslab Coordinates");
+    VERIFY(coords[3], 7, "Hyperslab Coordinates");
+    HDfree(coords);
+    ret = H5Sget_select_bounds(sid2, low, high);
+    CHECK(ret, FAIL, "H5Sget_select_bounds");
+    VERIFY(low[0], 2, "Selection Bounds");
+    VERIFY(low[1], 2, "Selection Bounds");
+    VERIFY(high[0], 7, "Selection Bounds");
+    VERIFY(high[1], 7, "Selection Bounds");
+
+    /* Close region space */
+    ret = H5Sclose(sid2);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Get the element selection */
+    sid2 = H5Rget_region(dset1, H5R_DATASET_REGION, &rbuf[1]);
+    CHECK(sid2, FAIL, "H5Rget_region");
+
+    /* Verify correct elements selected */
+    ret = (int)H5Sget_select_npoints(sid2);
+    VERIFY(ret, 10, "H5Sget_select_npoints");
+    ret = (int)H5Sget_select_elem_npoints(sid2);
+    VERIFY(ret, 10, "H5Sget_select_elem_npoints");
+    coords = (hsize_t *)HDmalloc((size_t)ret * SPACE2_RANK * sizeof(hsize_t)); /* allocate space for the element points */
+    ret = H5Sget_select_elem_pointlist(sid2, (hsize_t)0, (hsize_t)ret, coords);
+    CHECK(ret, FAIL, "H5Sget_select_elem_pointlist");
+    VERIFY(coords[0], coord1[0][0], "Element Coordinates");
+    VERIFY(coords[1], coord1[0][1], "Element Coordinates");
+    VERIFY(coords[2], coord1[1][0], "Element Coordinates");
+    VERIFY(coords[3], coord1[1][1], "Element Coordinates");
+    VERIFY(coords[4], coord1[2][0], "Element Coordinates");
+    VERIFY(coords[5], coord1[2][1], "Element Coordinates");
+    VERIFY(coords[6], coord1[3][0], "Element Coordinates");
+    VERIFY(coords[7], coord1[3][1], "Element Coordinates");
+    VERIFY(coords[8], coord1[4][0], "Element Coordinates");
+    VERIFY(coords[9], coord1[4][1], "Element Coordinates");
+    VERIFY(coords[10], coord1[5][0], "Element Coordinates");
+    VERIFY(coords[11], coord1[5][1], "Element Coordinates");
+    VERIFY(coords[12], coord1[6][0], "Element Coordinates");
+    VERIFY(coords[13], coord1[6][1], "Element Coordinates");
+    VERIFY(coords[14], coord1[7][0], "Element Coordinates");
+    VERIFY(coords[15], coord1[7][1], "Element Coordinates");
+    VERIFY(coords[16], coord1[8][0], "Element Coordinates");
+    VERIFY(coords[17], coord1[8][1], "Element Coordinates");
+    VERIFY(coords[18], coord1[9][0], "Element Coordinates");
+    VERIFY(coords[19], coord1[9][1], "Element Coordinates");
+    HDfree(coords);
+    ret = H5Sget_select_bounds(sid2, low, high);
+    CHECK(ret, FAIL, "H5Sget_select_bounds");
+    VERIFY(low[0], 0, "Selection Bounds");
+    VERIFY(low[1], 0, "Selection Bounds");
+    VERIFY(high[0], 9, "Selection Bounds");
+    VERIFY(high[1], 9, "Selection Bounds");
+
+    /* Close region space */
+    ret = H5Sclose(sid2);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    if(libver_high >= H5F_LIBVER_V110) {
+        /* Get the unlimited selection */
+        sid2 = H5Rget_region(dset1, H5R_DATASET_REGION, &rbuf[2]);
+        CHECK(sid2, FAIL, "H5Rget_region");
+
+        /* Verify correct hyperslab selected */
+        hssize_ret = H5Sget_select_npoints(sid2);
+        VERIFY(hssize_ret, (hssize_t)H5S_UNLIMITED, "H5Sget_select_npoints");
+        tri_ret = H5Sis_regular_hyperslab(sid2);
+        CHECK(tri_ret, FAIL, "H5Sis_regular_hyperslab");
+        VERIFY(tri_ret, TRUE, "H5Sis_regular_hyperslab Result");
+        ret = H5Sget_regular_hyperslab(sid2, start, stride, count, block);
+        CHECK(ret, FAIL, "H5Sget_regular_hyperslab");
+        VERIFY(start[0], (hsize_t)1, "Hyperslab Coordinates");
+        VERIFY(start[1], (hsize_t)8, "Hyperslab Coordinates");
+        VERIFY(stride[0], (hsize_t)4, "Hyperslab Coordinates");
+        VERIFY(stride[1], (hsize_t)1, "Hyperslab Coordinates");
+        VERIFY(count[0], H5S_UNLIMITED, "Hyperslab Coordinates");
+        VERIFY(count[1], (hsize_t)1, "Hyperslab Coordinates");
+        VERIFY(block[0], (hsize_t)2, "Hyperslab Coordinates");
+        VERIFY(block[1], (hsize_t)2, "Hyperslab Coordinates");
+
+        /* Close region space */
+        ret = H5Sclose(sid2);
+        CHECK(ret, FAIL, "H5Sclose");
+    }
+
+    /* Close first space */
+    ret = H5Sclose(sid1);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close dereferenced Dataset */
+    ret = H5Dclose(dset2);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Attempting to retrieve type of object using non-valid refs */
+    for(j = 0; j < 3; j++) {
+        H5E_BEGIN_TRY {
+            ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &nvrbuf[j], &obj_type);
+        } H5E_END_TRY;
+        VERIFY(ret, FAIL, "H5Rget_obj_type2");
+    } /* end for */
+
+    /* Close Dataset */
+    ret = H5Dclose(dset1);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close dataset access property list */
+    ret = H5Pclose(dapl_id);
+    CHECK(ret, FAIL, "H5Pclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Free memory buffers */
+    HDfree(wbuf);
+    HDfree(rbuf);
+    HDfree(dwbuf);
+    HDfree(drbuf);
+}   /* test_reference_region() */
+
+/****************************************************************
+**
+**  test_reference_region_1D(): Test H5R (reference) object reference code.
+**      Tests 1-D references to various kinds of objects
+**
+**  Note: The libver_low/libver_high parameters are added to create the file
+**        with the low and high bounds setting in fapl.
+**        Please see the RFC for "H5Sencode/H5Sdecode Format Change".
+**
+****************************************************************/
+static void
+test_reference_region_1D(H5F_libver_t libver_low, H5F_libver_t libver_high)
+{
+    hid_t fid1;        /* HDF5 File IDs        */
+    hid_t fapl = -1;    /* File access property list */
+    hid_t dset1,        /* Dataset ID            */
+          dset3;        /* Dereferenced dataset ID */
+    hid_t sid1,         /* Dataspace ID    #1        */
+          sid3;         /* Dataspace ID    #3        */
+    hid_t dapl_id;      /* Dataset access property list */
+    hsize_t dims1[] = {SPACE1_DIM1},
+            dims3[] = {SPACE3_DIM1};
+    hsize_t start[SPACE3_RANK];     /* Starting location of hyperslab */
+    hsize_t stride[SPACE3_RANK];    /* Stride of hyperslab */
+    hsize_t count[SPACE3_RANK];     /* Element count of hyperslab */
+    hsize_t block[SPACE3_RANK];     /* Block size of hyperslab */
+    hsize_t coord1[POINT1_NPOINTS][SPACE3_RANK]; /* Coordinates for point selection */
+    hsize_t *coords;                /* Coordinate buffer */
+    hsize_t low[SPACE3_RANK];       /* Selection bounds */
+    hsize_t high[SPACE3_RANK];      /* Selection bounds */
+    hdset_reg_ref_t *wbuf,          /* buffer to write to disk */
+                    *rbuf;          /* buffer read from disk */
+    uint8_t *dwbuf,  /* Buffer for writing numeric data to disk */
+            *drbuf;  /* Buffer for reading numeric data from disk */
+    uint8_t *tu8;    /* Temporary pointer to uint8 data */
+    H5O_type_t obj_type;            /* Object type */
+    int i;          /* counting variables */
+    herr_t ret;     /* Generic return value */
+
+    /* Output message about test being performed */
+    MESSAGE(5, ("Testing 1-D Dataset Region Reference Functions\n"));
+
+    /* Allocate write & read buffers */
+    wbuf = (hdset_reg_ref_t *)HDcalloc(sizeof(hdset_reg_ref_t), (size_t)SPACE1_DIM1);
+    rbuf = (hdset_reg_ref_t *)HDmalloc(sizeof(hdset_reg_ref_t) * SPACE1_DIM1);
+    dwbuf = (uint8_t *)HDmalloc(sizeof(uint8_t) * SPACE3_DIM1);
+    drbuf = (uint8_t *)HDcalloc(sizeof(uint8_t), (size_t)SPACE3_DIM1);
+
+    /* Create the file access property list */
+    fapl = H5Pcreate(H5P_FILE_ACCESS);
+    CHECK(fapl, FAIL, "H5Pcreate");
+
+    /* Set the low/high version bounds in fapl */
+    ret = H5Pset_libver_bounds(fapl, libver_low, libver_high);
+    CHECK(ret, FAIL, "H5Pset_libver_bounds");
+
+    /* Create file with the fapl */
+    fid1 = H5Fcreate(FILE2, H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
+    CHECK(fid1, FAIL, "H5Fcreate");
+
+    /* Create dataspace for datasets */
+    sid3 = H5Screate_simple(SPACE3_RANK, dims3, NULL);
+    CHECK(sid3, FAIL, "H5Screate_simple");
+
+    /* Create dataset access property list */
+    dapl_id = H5Pcreate(H5P_DATASET_ACCESS);
+    CHECK(dapl_id, FAIL, "H5Pcreate");
+
+    /* Create a dataset */
+    dset3 = H5Dcreate2(fid1, "Dataset2", H5T_STD_U8LE, sid3, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dset3, FAIL, "H5Dcreate2");
+
+    for(tu8 = dwbuf, i = 0; i < SPACE3_DIM1; i++)
+        *tu8++ = (uint8_t)(i * 3);
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dset3, H5T_STD_U8LE, H5S_ALL, H5S_ALL, H5P_DEFAULT, dwbuf);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close Dataset */
+    ret = H5Dclose(dset3);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create dataspace for the reference dataset */
+    sid1 = H5Screate_simple(SPACE1_RANK, dims1, NULL);
+    CHECK(sid1, FAIL, "H5Screate_simple");
+
+    /* Create a dataset */
+    dset1 = H5Dcreate2(fid1, "Dataset1", H5T_STD_REF_DSETREG, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Dcreate2");
+
+    /* Create references */
+
+    /* Select 15 2x1 hyperslabs for first reference */
+    start[0] = 2;
+    stride[0] = 5;
+    count[0] = 15;
+    block[0] = 2;
+    ret = H5Sselect_hyperslab(sid3, H5S_SELECT_SET, start, stride, count, block);
+    CHECK(ret, FAIL, "H5Sselect_hyperslab");
+
+    ret = (int)H5Sget_select_npoints(sid3);
+    VERIFY(ret, 30, "H5Sget_select_npoints");
+
+    /* Store first dataset region */
+    ret = H5Rcreate(&wbuf[0], fid1, "/Dataset2", H5R_DATASET_REGION, sid3);
+    CHECK(ret, FAIL, "H5Rcreate");
+    ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &wbuf[0], &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type2");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+
+    /* Select sequence of ten points for second reference */
+    coord1[0][0] = 16;
+    coord1[1][0] = 22;
+    coord1[2][0] = 38;
+    coord1[3][0] = 41;
+    coord1[4][0] = 52;
+    coord1[5][0] = 63;
+    coord1[6][0] = 70;
+    coord1[7][0] = 89;
+    coord1[8][0] = 97;
+    coord1[9][0] = 03;
+    ret = H5Sselect_elements(sid3, H5S_SELECT_SET, (size_t)POINT1_NPOINTS, (const hsize_t *)coord1);
+    CHECK(ret, FAIL, "H5Sselect_elements");
+
+    ret = (int)H5Sget_select_npoints(sid3);
+    VERIFY(ret, 10, "H5Sget_select_npoints");
+
+    /* Store second dataset region */
+    ret = H5Rcreate(&wbuf[1], fid1, "/Dataset2", H5R_DATASET_REGION, sid3);
+    CHECK(ret, FAIL, "H5Rcreate");
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dset1, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close disk dataspace */
+    ret = H5Sclose(sid1);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dset1);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close uint8 dataset dataspace */
+    ret = H5Sclose(sid3);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Re-open the file */
+    fid1 = H5Fopen(FILE2, H5F_ACC_RDWR, fapl);
+    CHECK(fid1, FAIL, "H5Fopen");
+
+    /* Open the dataset */
+    dset1 = H5Dopen2(fid1, "/Dataset1", H5P_DEFAULT);
+    CHECK(dset1, FAIL, "H5Dopen2");
+
+    /* Read selection from disk */
+    ret = H5Dread(dset1, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /* Try to open objects */
+    dset3 = H5Rdereference2(dset1, dapl_id, H5R_DATASET_REGION, &rbuf[0]);
+    CHECK(dset3, FAIL, "H5Rdereference2");
+
+    /* Check what H5Rget_obj_type2 function returns */
+    ret = H5Rget_obj_type2(dset1, H5R_DATASET_REGION, &rbuf[0], &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type2");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+
+    /* Check information in referenced dataset */
+    sid1 = H5Dget_space(dset3);
+    CHECK(sid1, FAIL, "H5Dget_space");
+
+    ret = (int)H5Sget_simple_extent_npoints(sid1);
+    VERIFY(ret, 100, "H5Sget_simple_extent_npoints");
+
+    /* Read from disk */
+    ret = H5Dread(dset3, H5T_STD_U8LE, H5S_ALL, H5S_ALL, H5P_DEFAULT, drbuf);
+    CHECK(ret, FAIL, "H5Dread");
+
+    for(tu8 = (uint8_t *)drbuf, i = 0; i < SPACE3_DIM1; i++, tu8++)
+        VERIFY(*tu8, (uint8_t)(i * 3), "Data");
+
+    /* Get the hyperslab selection */
+    sid3 = H5Rget_region(dset1, H5R_DATASET_REGION, &rbuf[0]);
+    CHECK(sid3, FAIL, "H5Rget_region");
+
+    /* Verify correct hyperslab selected */
+    ret = (int)H5Sget_select_npoints(sid3);
+    VERIFY(ret, 30, "H5Sget_select_npoints");
+    ret = (int)H5Sget_select_hyper_nblocks(sid3);
+    VERIFY(ret, 15, "H5Sget_select_hyper_nblocks");
+    coords = (hsize_t *)HDmalloc((size_t)ret * SPACE3_RANK * sizeof(hsize_t) * 2); /* allocate space for the hyperslab blocks */
+    ret = H5Sget_select_hyper_blocklist(sid3, (hsize_t)0, (hsize_t)ret, coords);
+    CHECK(ret, FAIL, "H5Sget_select_hyper_blocklist");
+    VERIFY(coords[0],   2, "Hyperslab Coordinates");
+    VERIFY(coords[1],   3, "Hyperslab Coordinates");
+    VERIFY(coords[2],   7, "Hyperslab Coordinates");
+    VERIFY(coords[3],   8, "Hyperslab Coordinates");
+    VERIFY(coords[4],  12, "Hyperslab Coordinates");
+    VERIFY(coords[5],  13, "Hyperslab Coordinates");
+    VERIFY(coords[6],  17, "Hyperslab Coordinates");
+    VERIFY(coords[7],  18, "Hyperslab Coordinates");
+    VERIFY(coords[8],  22, "Hyperslab Coordinates");
+    VERIFY(coords[9],  23, "Hyperslab Coordinates");
+    VERIFY(coords[10], 27, "Hyperslab Coordinates");
+    VERIFY(coords[11], 28, "Hyperslab Coordinates");
+    VERIFY(coords[12], 32, "Hyperslab Coordinates");
+    VERIFY(coords[13], 33, "Hyperslab Coordinates");
+    VERIFY(coords[14], 37, "Hyperslab Coordinates");
+    VERIFY(coords[15], 38, "Hyperslab Coordinates");
+    VERIFY(coords[16], 42, "Hyperslab Coordinates");
+    VERIFY(coords[17], 43, "Hyperslab Coordinates");
+    VERIFY(coords[18], 47, "Hyperslab Coordinates");
+    VERIFY(coords[19], 48, "Hyperslab Coordinates");
+    VERIFY(coords[20], 52, "Hyperslab Coordinates");
+    VERIFY(coords[21], 53, "Hyperslab Coordinates");
+    VERIFY(coords[22], 57, "Hyperslab Coordinates");
+    VERIFY(coords[23], 58, "Hyperslab Coordinates");
+    VERIFY(coords[24], 62, "Hyperslab Coordinates");
+    VERIFY(coords[25], 63, "Hyperslab Coordinates");
+    VERIFY(coords[26], 67, "Hyperslab Coordinates");
+    VERIFY(coords[27], 68, "Hyperslab Coordinates");
+    VERIFY(coords[28], 72, "Hyperslab Coordinates");
+    VERIFY(coords[29], 73, "Hyperslab Coordinates");
+    HDfree(coords);
+    ret = H5Sget_select_bounds(sid3, low, high);
+    CHECK(ret, FAIL, "H5Sget_select_bounds");
+    VERIFY(low[0], 2, "Selection Bounds");
+    VERIFY(high[0], 73, "Selection Bounds");
+
+    /* Close region space */
+    ret = H5Sclose(sid3);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Get the element selection */
+    sid3 = H5Rget_region(dset1, H5R_DATASET_REGION, &rbuf[1]);
+    CHECK(sid3, FAIL, "H5Rget_region");
+
+    /* Verify correct elements selected */
+    ret = (int)H5Sget_select_npoints(sid3);
+    VERIFY(ret, 10, "H5Sget_select_npoints");
+    ret = (int)H5Sget_select_elem_npoints(sid3);
+    VERIFY(ret, 10, "H5Sget_select_elem_npoints");
+    coords = (hsize_t *)HDmalloc((size_t)ret * SPACE3_RANK * sizeof(hsize_t)); /* allocate space for the element points */
+    ret = H5Sget_select_elem_pointlist(sid3, (hsize_t)0, (hsize_t)ret, coords);
+    CHECK(ret, FAIL, "H5Sget_select_elem_pointlist");
+    VERIFY(coords[0], coord1[0][0], "Element Coordinates");
+    VERIFY(coords[1], coord1[1][0], "Element Coordinates");
+    VERIFY(coords[2], coord1[2][0], "Element Coordinates");
+    VERIFY(coords[3], coord1[3][0], "Element Coordinates");
+    VERIFY(coords[4], coord1[4][0], "Element Coordinates");
+    VERIFY(coords[5], coord1[5][0], "Element Coordinates");
+    VERIFY(coords[6], coord1[6][0], "Element Coordinates");
+    VERIFY(coords[7], coord1[7][0], "Element Coordinates");
+    VERIFY(coords[8], coord1[8][0], "Element Coordinates");
+    VERIFY(coords[9], coord1[9][0], "Element Coordinates");
+    HDfree(coords);
+    ret = H5Sget_select_bounds(sid3, low, high);
+    CHECK(ret, FAIL, "H5Sget_select_bounds");
+    VERIFY(low[0], 3, "Selection Bounds");
+    VERIFY(high[0], 97, "Selection Bounds");
+
+    /* Close region space */
+    ret = H5Sclose(sid3);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close first space */
+    ret = H5Sclose(sid1);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close dereferenced Dataset */
+    ret = H5Dclose(dset3);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dset1);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close dataset access property list */
+    ret = H5Pclose(dapl_id);
+    CHECK(ret, FAIL, "H5Pclose");
+
+    /* Close file access property list */
+    ret = H5Pclose(fapl);
+    CHECK(ret, FAIL, "H5Pclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Free memory buffers */
+    HDfree(wbuf);
+    HDfree(rbuf);
+    HDfree(dwbuf);
+    HDfree(drbuf);
+}   /* test_reference_region_1D() */
+
+/****************************************************************
+**
+**  test_reference_obj_deleted(): Test H5R (reference) object reference code.
+**      Tests for correct failures for deleted and non-existent objects
+**
+****************************************************************/
+static void
+test_reference_obj_deleted(void)
+{
+    hid_t        fid1;        /* HDF5 File IDs        */
+    hid_t        dataset,    /* Dataset ID            */
+                dset2;      /* Dereferenced dataset ID */
+    hid_t        sid1;       /* Dataspace ID            */
+    hobj_ref_t  oref;       /* Object Reference to test */
+    H5O_type_t          obj_type;       /* Object type */
+    haddr_t addr = HADDR_UNDEF; /* test for undefined reference */
+    herr_t        ret;        /* Generic return value        */
+
+    /* Create file */
+    fid1 = H5Fcreate(FILE3, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid1, FAIL, "H5Fcreate");
+
+    /* Create scalar dataspace for datasets */
+    sid1 = H5Screate_simple(0, NULL, NULL);
+    CHECK(sid1, FAIL, "H5Screate_simple");
+
+    /* Create a dataset to reference (deleted later) */
+    dataset = H5Dcreate2(fid1, "Dataset1", H5T_NATIVE_INT, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create a dataset */
+    dataset = H5Dcreate2(fid1, "Dataset2", H5T_STD_REF_OBJ, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    /* Create reference to dataset */
+    ret = H5Rcreate(&oref, fid1, "/Dataset1", H5R_OBJECT, (hid_t)-1);
+    CHECK(ret, FAIL, "H5Rcreate");
+    ret = H5Rget_obj_type2(dataset, H5R_OBJECT, &oref, &obj_type);
+    CHECK(ret, FAIL, "H5Rget_obj_type2");
+    VERIFY(obj_type, H5O_TYPE_DATASET, "H5Rget_obj_type2");
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, &oref);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Delete referenced dataset */
+    ret = H5Ldelete(fid1, "/Dataset1", H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Ldelete");
+
+    /* Close disk dataspace */
+    ret = H5Sclose(sid1);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Re-open the file */
+    fid1 = H5Fopen(FILE3, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK(fid1, FAIL, "H5Fopen");
+
+    /* Open the dataset */
+    dataset = H5Dopen2(fid1, "/Dataset2", H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Dopen2");
+
+    /* Open undefined reference */
+    dset2 = H5Rdereference2(dataset, H5P_DEFAULT, H5R_OBJECT, &addr);
+    VERIFY(dset2, FAIL, "H5Rdereference2");
+
+    /* Read selection from disk */
+    HDmemset(&oref, 0, sizeof(hobj_ref_t));
+    ret = H5Dread(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, &oref);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /* Open deleted dataset object */
+    dset2 = H5Rdereference2(dataset, H5P_DEFAULT, H5R_OBJECT, &oref);
+    VERIFY(dset2, FAIL, "H5Rdereference2");
+
+    /* Open nonsense reference */
+    HDmemset(&oref, 0, sizeof(hobj_ref_t));
+    dset2 = H5Rdereference2(dataset, H5P_DEFAULT, H5R_OBJECT, &oref);
+    VERIFY(dset2, FAIL, "H5Rdereference2");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+}   /* test_reference_obj_deleted() */
+
+/****************************************************************
+**
+**  test_deref_iter_op(): Iterator callback for test_reference_group_iterate()
+**      test.
+**
+****************************************************************/
+static herr_t
+test_deref_iter_op(hid_t H5_ATTR_UNUSED group, const char *name, const H5L_info_t H5_ATTR_UNUSED *info,
+    void *op_data)
+{
+    int *count = (int *)op_data;        /* Pointer to name counter */
+    herr_t ret_value;
+
+    /* Simple check for correct names */
+    if(*count == 0) {
+        if(HDstrcmp(name, DSETNAME2) == 0)
+            ret_value = 0;
+        else
+            ret_value = -1;
+    } /* end if */
+    else if(*count == 1) {
+        if(HDstrcmp(name, GROUPNAME2) == 0)
+            ret_value = 0;
+        else
+            ret_value = -1;
+    } /* end if */
+    else if(*count == 2) {
+        if(HDstrcmp(name, GROUPNAME3) == 0)
+            ret_value = 0;
+        else
+            ret_value = -1;
+    } /* end if */
+    else
+        ret_value = -1;
+
+    (*count)++;
+
+    return(ret_value);
+} /* end test_deref_iter_op() */
+
+/****************************************************************
+**
+**  test_reference_group(): Test H5R (reference) object reference code.
+**      Tests for correct behavior of various routines on dereferenced group
+**
+****************************************************************/
+static void
+test_reference_group(void)
+{
+    hid_t fid = -1;             /* File ID */
+    hid_t gid = -1, gid2 = -1;  /* Group IDs */
+    hid_t did;                  /* Dataset ID */
+    hid_t sid;                  /* Dataspace ID */
+    hobj_ref_t wref;            /* Reference to write */
+    hobj_ref_t rref;            /* Reference to read */
+    H5G_info_t ginfo;           /* Group info struct */
+    char objname[NAME_SIZE];    /* Buffer to store name */
+    H5O_info_t oinfo;           /* Object info struct */
+    int count = 0;              /* Count within iterated group */
+    ssize_t size;               /* Name length */
+    herr_t ret;
+
+    /* Create file with a group and a dataset containing an object reference to the group */
+    fid = H5Fcreate(FILE1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid, FAIL, "H5Fcreate");
+
+    /* Create dataspace to use for dataset */
+    sid = H5Screate(H5S_SCALAR);
+    CHECK(sid, FAIL, "H5Screate");
+
+    /* Create group to refer to */
+    gid = H5Gcreate2(fid, GROUPNAME,  H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(gid, FAIL, "H5Gcreate2");
+
+    /* Create nested groups */
+    gid2 = H5Gcreate2(gid, GROUPNAME2,  H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(gid2, FAIL, "H5Gcreate2");
+    ret = H5Gclose(gid2);
+    CHECK(ret, FAIL, "H5Gclose");
+
+    gid2 = H5Gcreate2(gid, GROUPNAME3,  H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(gid2, FAIL, "H5Gcreate2");
+    ret = H5Gclose(gid2);
+    CHECK(ret, FAIL, "H5Gclose");
+
+    /* Create bottom dataset */
+    did = H5Dcreate2(gid, DSETNAME2, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    assert(did > 0);
+    ret = H5Dclose(did);
+    assert(ret >= 0);
+
+    ret = H5Gclose(gid);
+    CHECK(ret, FAIL, "H5Gclose");
+
+    /* Create dataset */
+    did = H5Dcreate2(fid, DSETNAME, H5T_STD_REF_OBJ, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(did, FAIL, "H5Dcreate2");
+
+    /* Create reference to group */
+    ret = H5Rcreate(&wref, fid, GROUPNAME, H5R_OBJECT, (hid_t)-1);
+    CHECK(ret, FAIL, "H5Rcreate");
+
+    /* Write reference to disk */
+    ret = H5Dwrite(did, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, &wref);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close objects */
+    ret = H5Dclose(did);
+    CHECK(ret, FAIL, "H5Dclose");
+    ret = H5Sclose(sid);
+    CHECK(ret, FAIL, "H5Sclose");
+    ret = H5Fclose(fid);
+    CHECK(ret, FAIL, "H5Fclose");
+
+
+    /* Re-open file */
+    fid = H5Fopen(FILE1, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK(fid, FAIL, "H5Fopen");
+
+    /* Re-open dataset */
+    did = H5Dopen2(fid, DSETNAME, H5P_DEFAULT);
+    CHECK(did, FAIL, "H5Dopen2");
+
+    /* Read in the reference */
+    ret = H5Dread(did, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, &rref);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /* Dereference to get the group */
+    gid = H5Rdereference2(did, H5P_DEFAULT, H5R_OBJECT, &rref);
+    CHECK(gid, FAIL, "H5Rdereference2");
+
+    /* Iterate through objects in dereferenced group */
+    ret = H5Literate(gid, H5_INDEX_NAME, H5_ITER_INC, NULL, test_deref_iter_op, &count);
+    CHECK(ret, FAIL, "H5Literate");
+
+    /* Various queries on the group opened */
+    ret = H5Gget_info(gid, &ginfo);
+    CHECK(ret, FAIL, "H5Gget_info");
+    VERIFY(ginfo.nlinks, 3, "H5Gget_info");
+
+    size = H5Lget_name_by_idx(gid, ".", H5_INDEX_NAME, H5_ITER_INC, (hsize_t)0, objname, (size_t)NAME_SIZE, H5P_DEFAULT);
+    CHECK(size, FAIL, "H5Lget_name_by_idx");
+    VERIFY_STR(objname, DSETNAME2, "H5Lget_name_by_idx");
+
+    ret = H5Oget_info_by_idx2(gid, ".", H5_INDEX_NAME, H5_ITER_INC, (hsize_t)0, &oinfo, H5O_INFO_BASIC, H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Oget_info_by_idx");
+    VERIFY(oinfo.type, H5O_TYPE_DATASET, "H5Oget_info_by_idx");
+
+    /* Unlink one of the objects in the dereferenced group */
+    ret = H5Ldelete(gid, GROUPNAME2, H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Ldelete");
+
+    /* Delete dataset object in dereferenced group (with other dataset still open) */
+    ret = H5Ldelete(gid, DSETNAME2, H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Ldelete");
+
+    /* Close objects */
+    ret = H5Dclose(did);
+    CHECK(ret, FAIL, "H5Dclose");
+    ret = H5Gclose(gid);
+    CHECK(ret, FAIL, "H5Gclose");
+    ret = H5Fclose(fid);
+    CHECK(ret, FAIL, "H5Fclose");
+}   /* test_reference_group() */
+
+#ifndef H5_NO_DEPRECATED_SYMBOLS
+/****************************************************************
+**
+**  test_reference_compat(): Test basic H5R (reference) object reference code.
+**      Tests deprecated API routines
+**
+****************************************************************/
+static void
+test_reference_compat(void)
+{
+    hid_t    fid1;        /* HDF5 File IDs        */
+    hid_t    dataset, dset2;    /* Dataset ID            */
+    hid_t    group, group2;  /* Group ID                     */
+    hid_t    sid1,           /* Dataspace IDs        */
+                sid2;
+    hid_t    tid1, tid2;     /* Datatype ID            */
+    hsize_t    dims1[] = {SPACE1_DIM1},
+                dims2[] = {SPACE2_DIM1, SPACE2_DIM2};
+    hsize_t    start[SPACE2_RANK];     /* Starting location of hyperslab */
+    hsize_t    stride[SPACE2_RANK];    /* Stride of hyperslab */
+    hsize_t    count[SPACE2_RANK];     /* Element count of hyperslab */
+    hsize_t    block[SPACE2_RANK];     /* Block size of hyperslab */
+    hsize_t    coord1[POINT1_NPOINTS][SPACE2_RANK]; /* Coordinates for point selection */
+    hobj_ref_t *wbuf_obj,       /* Buffer to write to disk */
+               *rbuf_obj;       /* Buffer read from disk */
+    hdset_reg_ref_t *wbuf_reg,  /* Buffer to write to disk */
+               *rbuf_reg;       /* Buffer read from disk */
+    H5G_obj_t   obj_type;       /* Object type */
+    herr_t    ret;        /* Generic return value        */
+
+    /* Output message about test being performed */
+    MESSAGE(5, ("Testing Deprecated Object Reference Functions\n"));
+
+    /* Allocate write & read buffers */
+    wbuf_obj = (hobj_ref_t *)HDcalloc(sizeof(hobj_ref_t), SPACE1_DIM1);
+    rbuf_obj = (hobj_ref_t *)HDmalloc(sizeof(hobj_ref_t) * SPACE1_DIM1);
+    wbuf_reg = (hdset_reg_ref_t *)HDcalloc(sizeof(hdset_reg_ref_t), SPACE1_DIM1);
+    rbuf_reg = (hdset_reg_ref_t *)HDmalloc(sizeof(hdset_reg_ref_t) * SPACE1_DIM1);
+
+    /* Create file */
+    fid1 = H5Fcreate(FILE1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(fid1, FAIL, "H5Fcreate");
+
+    /* Create dataspace for datasets */
+    sid1 = H5Screate_simple(SPACE1_RANK, dims1, NULL);
+    CHECK(sid1, FAIL, "H5Screate_simple");
+
+    /* Create another dataspace for datasets */
+    sid2 = H5Screate_simple(SPACE2_RANK, dims2, NULL);
+    CHECK(sid2, FAIL, "H5Screate_simple");
+
+    /* Create a group */
+    group = H5Gcreate2(fid1, "Group1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(group, FAIL, "H5Gcreate2");
+
+    /* Create a dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset1", H5T_NATIVE_UINT, sid2, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create another dataset (inside Group1) */
+    dataset = H5Dcreate2(group, "Dataset2", H5T_NATIVE_UCHAR, sid2, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Create a datatype to refer to */
+    tid1 = H5Tcreate(H5T_COMPOUND, sizeof(s1_t));
+    CHECK(tid1, FAIL, "H5Tcreate");
+
+    /* Insert fields */
+    ret = H5Tinsert(tid1, "a", HOFFSET(s1_t,a), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid1, "b", HOFFSET(s1_t,b), H5T_NATIVE_INT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    ret = H5Tinsert(tid1, "c", HOFFSET(s1_t,c), H5T_NATIVE_FLOAT);
+    CHECK(ret, FAIL, "H5Tinsert");
+
+    /* Save datatype for later */
+    ret = H5Tcommit2(group, "Datatype1", tid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Tcommit2");
+
+    /* Close datatype */
+    ret = H5Tclose(tid1);
+    CHECK(ret, FAIL, "H5Tclose");
+
+    /* Close group */
+    ret = H5Gclose(group);
+    CHECK(ret, FAIL, "H5Gclose");
+
+
+    /* Create a dataset with object reference datatype */
+    dataset = H5Dcreate2(fid1, "Dataset3", H5T_STD_REF_OBJ, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    /* Create reference to dataset */
+    ret = H5Rcreate(&wbuf_obj[0], fid1, "/Group1/Dataset1", H5R_OBJECT, (hid_t)-1);
+    CHECK(ret, FAIL, "H5Rcreate");
+
+    /* Create reference to dataset */
+    ret = H5Rcreate(&wbuf_obj[1], fid1, "/Group1/Dataset2", H5R_OBJECT, (hid_t)-1);
+    CHECK(ret, FAIL, "H5Rcreate");
+
+    /* Create reference to group */
+    ret = H5Rcreate(&wbuf_obj[2], fid1, "/Group1", H5R_OBJECT, (hid_t)-1);
+    CHECK(ret, FAIL, "H5Rcreate");
+
+    /* Create reference to named datatype */
+    ret = H5Rcreate(&wbuf_obj[3], fid1, "/Group1/Datatype1", H5R_OBJECT, (hid_t)-1);
+    CHECK(ret, FAIL, "H5Rcreate");
+
+    /* Write references to disk */
+    ret = H5Dwrite(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf_obj);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+
+    /* Create a dataset with region reference datatype */
+    dataset = H5Dcreate2(fid1, "Dataset4", H5T_STD_REF_DSETREG, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dcreate2");
+
+    /* Select 6x6 hyperslab for first reference */
+    start[0] = 2; start[1] = 2;
+    stride[0] = 1; stride[1] = 1;
+    count[0] = 1; count[1] = 1;
+    block[0] = 6; block[1] = 6;
+    ret = H5Sselect_hyperslab(sid2, H5S_SELECT_SET, start, stride, count, block);
+    CHECK(ret, FAIL, "H5Sselect_hyperslab");
+
+    /* Create first dataset region */
+    ret = H5Rcreate(&wbuf_reg[0], fid1, "/Group1/Dataset1", H5R_DATASET_REGION, sid2);
+    CHECK(ret, FAIL, "H5Rcreate");
+
+    /* Select sequence of ten points for second reference */
+    coord1[0][0] = 6; coord1[0][1] = 9;
+    coord1[1][0] = 2; coord1[1][1] = 2;
+    coord1[2][0] = 8; coord1[2][1] = 4;
+    coord1[3][0] = 1; coord1[3][1] = 6;
+    coord1[4][0] = 2; coord1[4][1] = 8;
+    coord1[5][0] = 3; coord1[5][1] = 2;
+    coord1[6][0] = 0; coord1[6][1] = 4;
+    coord1[7][0] = 9; coord1[7][1] = 0;
+    coord1[8][0] = 7; coord1[8][1] = 1;
+    coord1[9][0] = 3; coord1[9][1] = 3;
+    ret = H5Sselect_elements(sid2, H5S_SELECT_SET, (size_t)POINT1_NPOINTS, (const hsize_t *)coord1);
+    CHECK(ret, FAIL, "H5Sselect_elements");
+
+    /* Create second dataset region */
+    ret = H5Rcreate(&wbuf_reg[1], fid1, "/Group1/Dataset2", H5R_DATASET_REGION, sid2);
+    CHECK(ret, FAIL, "H5Rcreate");
+
+    /* Write selection to disk */
+    ret = H5Dwrite(dataset, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, wbuf_reg);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+
+    /* Close disk dataspaces */
+    ret = H5Sclose(sid1);
+    CHECK(ret, FAIL, "H5Sclose");
+    ret = H5Sclose(sid2);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+
+    /* Re-open the file */
+    fid1 = H5Fopen(FILE1, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK(fid1, FAIL, "H5Fopen");
+
+    /* Open the object reference dataset */
+    dataset = H5Dopen2(fid1, "/Dataset3", H5P_DEFAULT);
+    CHECK(dataset, FAIL, "H5Dopen2");
+
+    /* Read selection from disk */
+    ret = H5Dread(dataset, H5T_STD_REF_OBJ, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf_obj);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /* Verify type of objects pointed at */
+    obj_type = H5Rget_obj_type1(dataset, H5R_OBJECT, &rbuf_obj[0]);
+    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
+    VERIFY(obj_type, H5G_DATASET, "H5Rget_obj_type1");
+
+    obj_type = H5Rget_obj_type1(dataset, H5R_OBJECT, &rbuf_obj[1]);
+    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
+    VERIFY(obj_type, H5G_DATASET, "H5Rget_obj_type1");
+
+    obj_type = H5Rget_obj_type1(dataset, H5R_OBJECT, &rbuf_obj[2]);
+    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
+    VERIFY(obj_type, H5G_GROUP, "H5Rget_obj_type1");
+
+    obj_type = H5Rget_obj_type1(dataset, H5R_OBJECT, &rbuf_obj[3]);
+    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
+    VERIFY(obj_type, H5G_TYPE, "H5Rget_obj_type1");
+
+
+    /* Make sure the referenced objects can be opened */
+    dset2 = H5Rdereference1(dataset, H5R_OBJECT, &rbuf_obj[0]);
+    CHECK(dset2, FAIL, "H5Rdereference1");
+
+    ret = H5Dclose(dset2);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    dset2 = H5Rdereference1(dataset, H5R_OBJECT, &rbuf_obj[1]);
+    CHECK(dset2, FAIL, "H5Rdereference1");
+
+    ret = H5Dclose(dset2);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    group2 = H5Rdereference1(dataset, H5R_OBJECT, &rbuf_obj[2]);
+    CHECK(group2, FAIL, "H5Rdereference1");
+
+    ret = H5Gclose(group2);
+    CHECK(ret, FAIL, "H5Gclose");
+
+    tid2 = H5Rdereference1(dataset, H5R_OBJECT, &rbuf_obj[3]);
+    CHECK(tid2, FAIL, "H5Rdereference1");
+
+    ret = H5Tclose(tid2);
+    CHECK(ret, FAIL, "H5Tclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+
+    /* Open the dataset region reference dataset */
+    dataset = H5Dopen2(fid1, "/Dataset4", H5P_DEFAULT);
+    CHECK(ret, FAIL, "H5Dopen2");
+
+    /* Read selection from disk */
+    ret = H5Dread(dataset, H5T_STD_REF_DSETREG, H5S_ALL, H5S_ALL, H5P_DEFAULT, rbuf_reg);
+    CHECK(ret, FAIL, "H5Dread");
+
+    /* Verify type of objects pointed at */
+    obj_type = H5Rget_obj_type1(dataset, H5R_DATASET_REGION, &rbuf_reg[0]);
+    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
+    VERIFY(obj_type, H5G_DATASET, "H5Rget_obj_type1");
+
+    obj_type = H5Rget_obj_type1(dataset, H5R_DATASET_REGION, &rbuf_reg[1]);
+    CHECK(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
+    VERIFY(obj_type, H5G_DATASET, "H5Rget_obj_type1");
+
+    obj_type = H5Rget_obj_type1(dataset, H5R_DATASET_REGION, &rbuf_reg[2]);
+    VERIFY(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
+
+    obj_type = H5Rget_obj_type1(dataset, H5R_DATASET_REGION, &rbuf_reg[3]);
+    VERIFY(obj_type, H5G_UNKNOWN, "H5Rget_obj_type1");
+
+    /* Make sure the referenced objects can be opened */
+    dset2 = H5Rdereference1(dataset, H5R_DATASET_REGION, &rbuf_reg[0]);
+    CHECK(dset2, FAIL, "H5Rdereference1");
+
+    ret = H5Dclose(dset2);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    dset2 = H5Rdereference1(dataset, H5R_DATASET_REGION, &rbuf_reg[1]);
+    CHECK(dset2, FAIL, "H5Rdereference1");
+
+    ret = H5Dclose(dset2);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close Dataset */
+    ret = H5Dclose(dataset);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    /* Close file */
+    ret = H5Fclose(fid1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /* Free memory buffers */
+    HDfree(wbuf_obj);
+    HDfree(rbuf_obj);
+    HDfree(wbuf_reg);
+    HDfree(rbuf_reg);
+}   /* test_reference_compat() */
+#endif /* H5_NO_DEPRECATED_SYMBOLS */
+
+/****************************************************************
+**
+**  test_reference_deprec(): Main H5R reference testing routine.
+**
+****************************************************************/
+void
+test_reference_deprec(void)
+{
+    H5F_libver_t low, high;     /* Low and high bounds */
+
+    /* Output message about test being performed */
+    MESSAGE(5, ("Testing Deprecated References\n"));
+
+    test_reference_params();    /* Test for correct parameter checking */
+    test_reference_obj();       /* Test basic H5R object reference code */
+
+    /* Loop through all the combinations of low/high version bounds */
+    for(low = H5F_LIBVER_EARLIEST; low < H5F_LIBVER_NBOUNDS; H5_INC_ENUM(H5F_libver_t, low)) {
+        for(high = H5F_LIBVER_EARLIEST; high < H5F_LIBVER_NBOUNDS; H5_INC_ENUM(H5F_libver_t, high)) {
+
+            /* Invalid combinations, just continue */
+            if(high == H5F_LIBVER_EARLIEST || high < low)
+                continue;
+
+            test_reference_region(low, high);       /* Test basic H5R dataset region reference code */
+            test_reference_region_1D(low, high);    /* Test H5R dataset region reference code for 1-D datasets */
+
+        } /* end high bound */
+    } /* end low bound */
+
+    test_reference_obj_deleted(); /* Test H5R object reference code for deleted objects */
+    test_reference_group();     /* Test operations on dereferenced groups */
+#ifndef H5_NO_DEPRECATED_SYMBOLS
+    test_reference_compat();    /* Test operations with old API routines */
+#endif /* H5_NO_DEPRECATED_SYMBOLS */
+
+}   /* test_reference() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    cleanup_reference
+ *
+ * Purpose:    Cleanup temporary test files
+ *
+ * Return:    none
+ *
+ * Programmer:    Quincey Koziol
+ *              September 8, 1998
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+void
+cleanup_reference_deprec(void)
+{
+    HDremove(FILE1);
+    HDremove(FILE2);
+    HDremove(FILE3);
+}
+