[svn-r23601] Bring revisions #23341 - 23597 from trunk to revise_chunks.

h5committtested.

28 files changed, 1085 insertions, 253 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 31b7f3d..828d2f0 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -490,6 +490,15 @@ SET (H5P_HDRS
 )
 IDE_GENERATED_PROPERTIES ("H5P" "${H5P_HDRS}" "${H5P_SRCS}" )
 
+SET (H5PL_SRCS
+    ${HDF5_SRC_DIR}/H5PL.c
+)
+
+SET (H5PL_HDRS
+    ${HDF5_SRC_DIR}/H5PLextern.h
+)
+IDE_GENERATED_PROPERTIES ("H5PL" "${H5PL_HDRS}" "${H5PL_SRCS}" )
+
 
 SET (H5R_SRCS
     ${HDF5_SRC_DIR}/H5R.c
@@ -675,6 +684,7 @@ SET (common_SRCS
     ${H5MP_SRCS}
     ${H5O_SRCS}
     ${H5P_SRCS}
+    ${H5PL_SRCS}
     ${H5R_SRCS}
     ${H5RC_SRCS}
     ${H5RS_SRCS}
@@ -714,6 +724,7 @@ SET (H5_PUBLIC_HEADERS
     ${H5MP_HDRS}
     ${H5O_HDRS}
     ${H5P_HDRS}
+    ${H5PL_HDRS}
     ${H5R_HDRS}
     ${H5S_HDRS}
     ${H5SM_HDRS}
@@ -752,6 +763,7 @@ SET (H5_PRIVATE_HEADERS
     ${HDF5_SRC_DIR}/H5MPprivate.h
     ${HDF5_SRC_DIR}/H5Oprivate.h
     ${HDF5_SRC_DIR}/H5Pprivate.h
+    ${HDF5_SRC_DIR}/H5PLprivate.h
     ${HDF5_SRC_DIR}/H5RCprivate.h
     ${HDF5_SRC_DIR}/H5Rprivate.h
     ${HDF5_SRC_DIR}/H5RSprivate.h
@@ -838,6 +850,9 @@ SET_SOURCE_FILES_PROPERTIES (${HDF5_BINARY_DIR}/H5overflow.h GENERATED)
 
 ADD_LIBRARY (${HDF5_LIB_TARGET} ${LIB_TYPE} ${common_SRCS} ${H5_PUBLIC_HEADERS} ${H5_PRIVATE_HEADERS})
 TARGET_LINK_LIBRARIES (${HDF5_LIB_TARGET} ${LINK_LIBS})
+IF (NOT WIN32)
+  TARGET_LINK_LIBRARIES (${HDF5_LIB_TARGET} dl)
+ENDIF (NOT WIN32)
 SET_GLOBAL_VARIABLE (HDF5_LIBRARIES_TO_EXPORT ${HDF5_LIB_TARGET})
 H5_SET_LIB_OPTIONS (${HDF5_LIB_TARGET} ${HDF5_LIB_NAME} ${LIB_TYPE})
 SET_TARGET_PROPERTIES (${HDF5_LIB_TARGET} PROPERTIES FOLDER libraries)
diff --git a/src/H5.c b/src/H5.c
index 14ec7ca..25525a4 100644
--- a/src/H5.c
+++ b/src/H5.c
@@ -271,6 +271,7 @@ H5_term_library(void)
             pending += DOWN(Z);
             pending += DOWN(FD);
             pending += DOWN(P);
+            pending += DOWN(PL);
             /* Don't shut down the error code until other APIs which use it are shut down */
             if(pending == 0)
                 pending += DOWN(E);
diff --git a/src/H5AC.c b/src/H5AC.c
index 18289e7..c075069 100644
--- a/src/H5AC.c
+++ b/src/H5AC.c
@@ -263,6 +263,7 @@ H5AC_init_interface(void)
     H5P_genclass_t  *xfer_pclass;   /* Dataset transfer property list class object */
     H5P_genplist_t  *xfer_plist;    /* Dataset transfer property list object */
     unsigned block_before_meta_write; /* "block before meta write" property value */
+    unsigned coll_meta_write;       /* "collective metadata write" property value */
     unsigned library_internal=1;    /* "library internal" property value */
     H5FD_mpio_xfer_t xfer_mode;     /* I/O transfer mode property value */
     herr_t ret_value=SUCCEED;           /* Return value */
@@ -276,6 +277,7 @@ H5AC_init_interface(void)
     if (NULL == (xfer_pclass = H5I_object(H5P_CLS_DATASET_XFER_g)))
         HGOTO_ERROR(H5E_CACHE, H5E_BADATOM, FAIL, "can't get property list class")
 
+
     /* Get an ID for the blocking, collective H5AC dxpl */
     if ((H5AC_dxpl_id=H5P_create_id(xfer_pclass,FALSE)) < 0)
         HGOTO_ERROR(H5E_CACHE, H5E_CANTCREATE, FAIL, "unable to register property list")
@@ -295,10 +297,12 @@ H5AC_init_interface(void)
                   NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL)<0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't insert metadata cache dxpl property")
 
-    /* Set the transfer mode */
-    xfer_mode=H5FD_MPIO_COLLECTIVE;
-    if (H5P_set(xfer_plist,H5D_XFER_IO_XFER_MODE_NAME,&xfer_mode)<0)
-        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "unable to set value")
+    /* Insert 'collective metadata write' property */
+    coll_meta_write = 1;
+    if(H5P_insert(xfer_plist, H5AC_COLLECTIVE_META_WRITE_NAME, H5AC_COLLECTIVE_META_WRITE_SIZE, &coll_meta_write,
+                  NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't insert metadata cache dxpl property")
+
 
     /* Get an ID for the non-blocking, collective H5AC dxpl */
     if ((H5AC_noblock_dxpl_id=H5P_create_id(xfer_pclass,FALSE)) < 0)
@@ -319,10 +323,12 @@ H5AC_init_interface(void)
                   NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL)<0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't insert metadata cache dxpl property")
 
-    /* Set the transfer mode */
-    xfer_mode=H5FD_MPIO_COLLECTIVE;
-    if (H5P_set(xfer_plist,H5D_XFER_IO_XFER_MODE_NAME,&xfer_mode)<0)
-        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "unable to set value")
+    /* Insert 'collective metadata write' property */
+    coll_meta_write = 1;
+    if(H5P_insert(xfer_plist, H5AC_COLLECTIVE_META_WRITE_NAME, H5AC_COLLECTIVE_META_WRITE_SIZE, &coll_meta_write,
+                  NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't insert metadata cache dxpl property")
+
 
     /* Get an ID for the non-blocking, independent H5AC dxpl */
     if ((H5AC_ind_dxpl_id=H5P_create_id(xfer_pclass,FALSE)) < 0)
@@ -343,10 +349,11 @@ H5AC_init_interface(void)
                   NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL)<0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't insert metadata cache dxpl property")
 
-    /* Set the transfer mode */
-    xfer_mode=H5FD_MPIO_INDEPENDENT;
-    if (H5P_set(xfer_plist,H5D_XFER_IO_XFER_MODE_NAME,&xfer_mode)<0)
-        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "unable to set value")
+    /* Insert 'collective metadata write' property */
+    coll_meta_write = 0;
+    if(H5P_insert(xfer_plist, H5AC_COLLECTIVE_META_WRITE_NAME, H5AC_COLLECTIVE_META_WRITE_SIZE, &coll_meta_write,
+                  NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't insert metadata cache dxpl property")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -3014,7 +3021,7 @@ done:
  *-------------------------------------------------------------------------
  */
 #ifdef H5_HAVE_PARALLEL
-herr_t
+static herr_t
 H5AC_construct_candidate_list(H5AC_t * cache_ptr,
                               H5AC_aux_t * aux_ptr,
                               int sync_point_op)
@@ -3228,7 +3235,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-herr_t
+static herr_t
 H5AC_ext_config_2_int_config(H5AC_cache_config_t * ext_conf_ptr,
                              H5C_auto_size_ctl_t * int_conf_ptr)
 {
@@ -4173,7 +4180,7 @@ done:
  *-------------------------------------------------------------------------
  */
 #ifdef H5_HAVE_PARALLEL
-herr_t
+static herr_t
 H5AC_propagate_flushed_and_still_clean_entries_list(H5F_t  * f,
                                                     hid_t    dxpl_id,
                                                     H5AC_t * cache_ptr)
diff --git a/src/H5ACprivate.h b/src/H5ACprivate.h
index 16a28f9..2f26094 100644
--- a/src/H5ACprivate.h
+++ b/src/H5ACprivate.h
@@ -208,6 +208,11 @@ typedef H5C_t	H5AC_t;
 #define H5AC_BLOCK_BEFORE_META_WRITE_SIZE       sizeof(unsigned)
 #define H5AC_BLOCK_BEFORE_META_WRITE_DEF        0
 
+/* Definitions for "collective metadata write" property */
+#define H5AC_COLLECTIVE_META_WRITE_NAME         "H5AC_collective_metadata_write"
+#define H5AC_COLLECTIVE_META_WRITE_SIZE         sizeof(unsigned)
+#define H5AC_COLLECTIVE_META_WRITE_DEF          0
+
 /* Definitions for "library internal" property */
 #define H5AC_LIBRARY_INTERNAL_NAME       "H5AC_library_internal"
 #define H5AC_LIBRARY_INTERNAL_SIZE       sizeof(unsigned)
diff --git a/src/H5C.c b/src/H5C.c
index 4d7788f..a653a17 100644
--- a/src/H5C.c
+++ b/src/H5C.c
@@ -75,6 +75,9 @@
 
 
 #include "H5private.h"		/* Generic Functions			*/
+#ifdef H5_HAVE_PARALLEL
+#include "H5ACprivate.h"        /* Metadata cache                       */
+#endif /* H5_HAVE_PARALLEL */
 #include "H5Cpkg.h"		/* Cache				*/
 #include "H5Dprivate.h"		/* Dataset functions			*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
@@ -8124,37 +8127,27 @@ H5C_flush_single_entry(H5F_t *	   	   f,
 
 #ifdef H5_HAVE_PARALLEL
 #ifndef NDEBUG
-
         /* If MPI based VFD is used, do special parallel I/O sanity checks.
          * Note that we only do these sanity checks when the clear_only flag
          * is not set, and the entry to be flushed is dirty.  Don't bother
          * otherwise as no file I/O can result.
          */
-        if ( ( ! clear_only ) &&
-             ( entry_ptr->is_dirty ) &&
-             (H5F_HAS_FEATURE(f, H5FD_FEAT_HAS_MPI) ) ) {
-
-            H5P_genplist_t *dxpl;           /* Dataset transfer property list */
-            H5FD_mpio_xfer_t xfer_mode;     /* I/O xfer mode property value */
+        if(!clear_only && entry_ptr->is_dirty &&
+                H5F_HAS_FEATURE(f, H5FD_FEAT_HAS_MPI)) {
+            H5P_genplist_t *dxpl;       /* Dataset transfer property list */
+            unsigned coll_meta;         /* Collective metadata write flag */
 
             /* Get the dataset transfer property list */
-            if ( NULL == (dxpl = H5I_object(primary_dxpl_id)) ) {
-
-                HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, \
-                            "not a dataset transfer property list")
-            }
+            if(NULL == (dxpl = H5I_object(primary_dxpl_id)))
+                HGOTO_ERROR(H5E_CACHE, H5E_BADTYPE, FAIL, "not a dataset transfer property list")
 
-            /* Get the transfer mode property */
-            if( H5P_get(dxpl, H5D_XFER_IO_XFER_MODE_NAME, &xfer_mode) < 0 ) {
-
-                HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, \
-                            "can't retrieve xfer mode")
-            }
-
-            /* Sanity check transfer mode */
-            HDassert( xfer_mode == H5FD_MPIO_COLLECTIVE );
-        }
+            /* Get the collective metadata write property */
+            if(H5P_get(dxpl, H5AC_COLLECTIVE_META_WRITE_NAME, &coll_meta) < 0)
+                HGOTO_ERROR(H5E_CACHE, H5E_CANTGET, FAIL, "can't retrieve xfer mode")
 
+            /* Sanity check collective metadata write flag */
+            HDassert(coll_meta);
+        } /* end if */
 #endif /* NDEBUG */
 #endif /* H5_HAVE_PARALLEL */
 
diff --git a/src/H5Dchunk.c b/src/H5Dchunk.c
index fb4f35f..0678eba 100644
--- a/src/H5Dchunk.c
+++ b/src/H5Dchunk.c
@@ -2237,7 +2237,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-herr_t
+static herr_t
 H5D__chunk_cinfo_cache_reset(H5D_chunk_cached_t *last)
 {
     FUNC_ENTER_PACKAGE_NOERR
diff --git a/src/H5Edefin.h b/src/H5Edefin.h
index 2ae79e5..183f72c 100644
--- a/src/H5Edefin.h
+++ b/src/H5Edefin.h
@@ -25,6 +25,7 @@ hid_t H5E_FUNC_g           = FAIL;      /* Function entry/exit */
 hid_t H5E_FILE_g           = FAIL;      /* File accessibilty */
 hid_t H5E_SOHM_g           = FAIL;      /* Shared Object Header Messages */
 hid_t H5E_SYM_g            = FAIL;      /* Symbol table */
+hid_t H5E_PLUGIN_g         = FAIL;      /* Plugin for dynamically loaded library */
 hid_t H5E_VFL_g            = FAIL;      /* Virtual File Layer */
 hid_t H5E_INTERNAL_g       = FAIL;      /* Internal error (too specific to document in detail) */
 hid_t H5E_BTREE_g          = FAIL;      /* B-Tree node */
@@ -131,6 +132,9 @@ hid_t H5E_PATH_g           = FAIL;      /* Problem with path to object */
 /* No error */
 hid_t H5E_NONE_MINOR_g     = FAIL;      /* No error */
 
+/* Plugin errors */
+hid_t H5E_OPENERROR_g      = FAIL;      /* Can't open directory or file */
+
 /* File accessibilty errors */
 hid_t H5E_FILEEXISTS_g     = FAIL;      /* File already exists */
 hid_t H5E_FILEOPEN_g       = FAIL;      /* File already open */
diff --git a/src/H5Einit.h b/src/H5Einit.h
index a2eb02f..9724748 100644
--- a/src/H5Einit.h
+++ b/src/H5Einit.h
@@ -44,6 +44,11 @@ if((msg = H5E_create_msg(cls, H5E_MAJOR, "Symbol table"))==NULL)
     HGOTO_ERROR(H5E_ERROR, H5E_CANTINIT, FAIL, "error message initialization failed")
 if((H5E_SYM_g = H5I_register(H5I_ERROR_MSG, msg, FALSE))<0)
     HGOTO_ERROR(H5E_ERROR, H5E_CANTREGISTER, FAIL, "can't register error message")
+assert(H5E_PLUGIN_g==(-1));
+if((msg = H5E_create_msg(cls, H5E_MAJOR, "Plugin for dynamically loaded library"))==NULL)
+    HGOTO_ERROR(H5E_ERROR, H5E_CANTINIT, FAIL, "error message initialization failed")
+if((H5E_PLUGIN_g = H5I_register(H5I_ERROR_MSG, msg, FALSE))<0)
+    HGOTO_ERROR(H5E_ERROR, H5E_CANTREGISTER, FAIL, "can't register error message")
 assert(H5E_VFL_g==(-1));
 if((msg = H5E_create_msg(cls, H5E_MAJOR, "Virtual File Layer"))==NULL)
     HGOTO_ERROR(H5E_ERROR, H5E_CANTINIT, FAIL, "error message initialization failed")
@@ -477,6 +482,13 @@ if((msg = H5E_create_msg(cls, H5E_MINOR, "No error"))==NULL)
 if((H5E_NONE_MINOR_g = H5I_register(H5I_ERROR_MSG, msg, FALSE))<0)
     HGOTO_ERROR(H5E_ERROR, H5E_CANTREGISTER, FAIL, "can't register error message")
 
+/* Plugin errors */
+assert(H5E_OPENERROR_g==(-1));
+if((msg = H5E_create_msg(cls, H5E_MINOR, "Can't open directory or file"))==NULL)
+    HGOTO_ERROR(H5E_ERROR, H5E_CANTINIT, FAIL, "error message initialization failed")
+if((H5E_OPENERROR_g = H5I_register(H5I_ERROR_MSG, msg, FALSE))<0)
+    HGOTO_ERROR(H5E_ERROR, H5E_CANTREGISTER, FAIL, "can't register error message")
+
 /* File accessibilty errors */
 assert(H5E_FILEEXISTS_g==(-1));
 if((msg = H5E_create_msg(cls, H5E_MINOR, "File already exists"))==NULL)
diff --git a/src/H5Epubgen.h b/src/H5Epubgen.h
index ddfb1d3..e79106f 100644
--- a/src/H5Epubgen.h
+++ b/src/H5Epubgen.h
@@ -28,6 +28,7 @@
 #define H5E_FILE             (H5OPEN H5E_FILE_g)
 #define H5E_SOHM             (H5OPEN H5E_SOHM_g)
 #define H5E_SYM              (H5OPEN H5E_SYM_g)
+#define H5E_PLUGIN           (H5OPEN H5E_PLUGIN_g)
 #define H5E_VFL              (H5OPEN H5E_VFL_g)
 #define H5E_INTERNAL         (H5OPEN H5E_INTERNAL_g)
 #define H5E_BTREE            (H5OPEN H5E_BTREE_g)
@@ -60,6 +61,7 @@ H5_DLLVAR hid_t H5E_FUNC_g;          /* Function entry/exit */
 H5_DLLVAR hid_t H5E_FILE_g;          /* File accessibilty */
 H5_DLLVAR hid_t H5E_SOHM_g;          /* Shared Object Header Messages */
 H5_DLLVAR hid_t H5E_SYM_g;           /* Symbol table */
+H5_DLLVAR hid_t H5E_PLUGIN_g;        /* Plugin for dynamically loaded library */
 H5_DLLVAR hid_t H5E_VFL_g;           /* Virtual File Layer */
 H5_DLLVAR hid_t H5E_INTERNAL_g;      /* Internal error (too specific to document in detail) */
 H5_DLLVAR hid_t H5E_BTREE_g;         /* B-Tree node */
@@ -221,6 +223,10 @@ H5_DLLVAR hid_t H5E_PATH_g;          /* Problem with path to object */
 #define H5E_NONE_MINOR       (H5OPEN H5E_NONE_MINOR_g)
 H5_DLLVAR hid_t H5E_NONE_MINOR_g;    /* No error */
 
+/* Plugin errors */
+#define H5E_OPENERROR        (H5OPEN H5E_OPENERROR_g)
+H5_DLLVAR hid_t H5E_OPENERROR_g;     /* Can't open directory or file */
+
 /* File accessibilty errors */
 #define H5E_FILEEXISTS       (H5OPEN H5E_FILEEXISTS_g)
 #define H5E_FILEOPEN         (H5OPEN H5E_FILEOPEN_g)
diff --git a/src/H5Eterm.h b/src/H5Eterm.h
index 6c621bc..5db503c 100644
--- a/src/H5Eterm.h
+++ b/src/H5Eterm.h
@@ -26,6 +26,7 @@ H5E_FUNC_g=
 H5E_FILE_g=    
 H5E_SOHM_g=    
 H5E_SYM_g=    
+H5E_PLUGIN_g=    
 H5E_VFL_g=    
 H5E_INTERNAL_g=    
 H5E_BTREE_g=    
@@ -133,6 +134,9 @@ H5E_PATH_g=
 /* No error */    
 H5E_NONE_MINOR_g=
 
+/* Plugin errors */    
+H5E_OPENERROR_g=
+
 /* File accessibilty errors */    
 H5E_FILEEXISTS_g=    
 H5E_FILEOPEN_g=    
diff --git a/src/H5FDmulti.c b/src/H5FDmulti.c
index 5bdfbbe..a3ce7f8 100644
--- a/src/H5FDmulti.c
+++ b/src/H5FDmulti.c
@@ -73,10 +73,6 @@
 
 #define END_MEMBERS	}}
 
-
-#define H5FD_MULTI_DXPL_PROP_NAME       "H5FD_MULTI_DXPL"
-#define H5FD_MULTI_DXPL_PROP_SIZE       sizeof(H5FD_multi_dxpl_t)
-
 #define H5FD_MULT_MAX_FILE_NAME_LEN     1024
 
 /* The driver identification number, initialized at runtime */
@@ -726,150 +722,6 @@ H5FD_multi_dxpl_cls_cb(const char *name, size_t size, void *_dx)
     return 0;
 } /* end H5FD_multi_dxpl_cls_cb() */
 
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5Pset_dxpl_multi
- *
- * Purpose:	Set the data transfer property list DXPL_ID to use the multi
- *		driver with the specified data transfer properties for each
- *		memory usage type MEMB_DXPL[] (after the usage map is
- *		applied).
- *
- * Return:	Success:	0
- *
- *		Failure:	-1
- *
- * Programmer:	Robb Matzke
- *              Tuesday, August 10, 1999
- *
- * Modifications:
- *
- *-------------------------------------------------------------------------
- */
-herr_t
-H5Pset_dxpl_multi(hid_t dxpl_id, const hid_t *memb_dxpl)
-{
-    H5FD_multi_dxpl_t	dx;
-    H5FD_mem_t		mt;
-    htri_t              prop_exists;            /* Whether the multi VFD DXPL property already exists */
-    static const char *func = "H5FDset_dxpl_multi";  /* Function Name for error reporting */
-
-    /*NO TRACE*/
-
-    /* Clear the error stack */
-    H5Eclear2(H5E_DEFAULT);
-
-    /* Check arguments */
-    if(TRUE != H5Pisa_class(dxpl_id,  H5P_DATASET_XFER))
-        H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_BADTYPE, "not a data transfer property list", -1)
-    if(!memb_dxpl)
-        H5Epush_ret(func, H5E_ERR_CLS, H5E_INTERNAL, H5E_BADVALUE, "invalid pointer", -1)
-    for(mt = H5FD_MEM_DEFAULT; mt < H5FD_MEM_NTYPES; mt = (H5FD_mem_t)(mt + 1)) {
-        if(memb_dxpl[mt] != H5P_DEFAULT && TRUE != H5Pisa_class(memb_dxpl[mt], H5P_DATASET_XFER))
-            H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_BADTYPE, "not a data transfer property list", -1)
-    } /* end for */
-
-    /* Check for existence of multi VFD DXPL property in DXPL */
-    if((prop_exists = H5Pexist(dxpl_id, H5FD_MULTI_DXPL_PROP_NAME)) < 0)
-        H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTGET, "can't check for multi VFD property", -1)
-
-    /* Copy the DXPLs to internal property, converting "generic" default
-     * property lists into default dataset transfer property lists */
-    for(mt = H5FD_MEM_DEFAULT; mt < H5FD_MEM_NTYPES; mt = (H5FD_mem_t)(mt + 1)) {
-        if(memb_dxpl[mt] == H5P_DEFAULT)
-            dx.memb_dxpl[mt] = H5P_DATASET_XFER_DEFAULT;
-        else {
-            if((dx.memb_dxpl[mt] = H5Pcopy(memb_dxpl[mt])) < 0)
-                H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTCOPY, "can't copy dataset transfer property list", -1)
-        } /* end else */
-    } /* end for */
-
-    /* Clear previous property, if it exists */
-    if(prop_exists) {
-        H5FD_multi_dxpl_t	old_dx;
-
-        /* Get the old DXPL value */
-        if(H5Pget(dxpl_id, H5FD_MULTI_DXPL_PROP_NAME, &old_dx) < 0)
-            H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTGET, "can't get previous property value", -1)
-
-        ALL_MEMBERS(mt) {
-            if(old_dx.memb_dxpl[mt] >= 0)
-                if(H5Pclose(old_dx.memb_dxpl[mt]) < 0)
-                    H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTCLOSEOBJ, "can't close property list", -1)
-        } END_MEMBERS;
-
-        /* Set the new value */
-        if(H5Pset(dxpl_id, H5FD_MULTI_DXPL_PROP_NAME, &dx) < 0)
-            H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTGET, "can't get previous property value", -1)
-    } /* end if */
-    else {
-        /* Insert multi VFD DXPL property into property list */
-        if(H5Pinsert2(dxpl_id, H5FD_MULTI_DXPL_PROP_NAME, H5FD_MULTI_DXPL_PROP_SIZE, &dx, NULL, NULL, NULL, H5FD_multi_dxpl_copy_cb, H5FD_multi_dxpl_cmp_cb, H5FD_multi_dxpl_cls_cb) < 0)
-            H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTINSERT, "can't insert multi VFD DXPL property", -1)
-    } /* end else */
-
-    return 0;
-} /* end H5Pset_dxpl_multi() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5Pget_dxpl_multi
- *
- * Purpose:	Returns information which was set with H5Pset_dxpl_multi()
- *		above.
- *
- * Return:	Success:	0
- *
- *		Failure:	-1
- *
- * Programmer:	Robb Matzke
- *              Tuesday, August 10, 1999
- *
- * Modifications:
- *
- *-------------------------------------------------------------------------
- */
-herr_t
-H5Pget_dxpl_multi(hid_t dxpl_id, hid_t *memb_dxpl/*out*/)
-{
-    H5FD_multi_dxpl_t	dx;
-    H5FD_mem_t		mt;
-    htri_t              prop_exists;            /* Whether the multi VFD DXPL property already exists */
-    static const char *func = "H5FDget_dxpl_multi";  /* Function Name for error reporting */
-
-    /*NO TRACE*/
-
-    /* Clear the error stack */
-    H5Eclear2(H5E_DEFAULT);
-
-    /* Argument checking */
-    if(TRUE != H5Pisa_class(dxpl_id, H5P_DATASET_XFER))
-        H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_BADTYPE, "not a file access property list", -1)
-
-    if(memb_dxpl) {
-        /* Check for existence of multi VFD DXPL property in DXPL */
-        if((prop_exists = H5Pexist(dxpl_id, H5FD_MULTI_DXPL_PROP_NAME)) < 0)
-            H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTGET, "can't check for multi VFD property", -1)
-        if(!prop_exists)
-            H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTGET, "multi VFD DXPL property not set", -1)
-
-        /* Get the DXPL value */
-        if(H5Pget(dxpl_id, H5FD_MULTI_DXPL_PROP_NAME, &dx) < 0)
-            H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTGET, "can't get property value", -1)
-
-        /* Deep copy the multi VFD DXPL value */
-	for(mt = H5FD_MEM_DEFAULT; mt < H5FD_MEM_NTYPES; mt = (H5FD_mem_t)(mt + 1)) {
-	    if(dx.memb_dxpl[mt] >= 0)
-		memb_dxpl[mt] = H5Pcopy(dx.memb_dxpl[mt]);
-	    else
-		memb_dxpl[mt] = dx.memb_dxpl[mt]; /*default or bad ID */
-	} /* end for */
-    } /* end if */
-
-    return 0;
-} /* end H5Pget_dxpl_multi() */
-
 
 /*-------------------------------------------------------------------------
  * Function:	H5FD_multi_sb_size
@@ -1936,18 +1788,6 @@ H5FD_multi_read(H5FD_t *_file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr,
     /* Clear the error stack */
     H5Eclear2(H5E_DEFAULT);
 
-    /* Get the data transfer properties */
-    if(H5P_FILE_ACCESS_DEFAULT != dxpl_id) {
-        /* Check for existence of multi VFD DXPL property in DXPL */
-        if((prop_exists = H5Pexist(dxpl_id, H5FD_MULTI_DXPL_PROP_NAME)) < 0)
-            H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTGET, "can't check for multi VFD property", -1)
-
-        /* Get the DXPL value, if it exists */
-        if(prop_exists)
-            if(H5Pget(dxpl_id, H5FD_MULTI_DXPL_PROP_NAME, &dx) < 0)
-                H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTGET, "can't get property value", -1)
-    } /* end if */
-
     /* Find the file to which this address belongs */
     for(mt = H5FD_MEM_SUPER; mt < H5FD_MEM_NTYPES; mt = (H5FD_mem_t)(mt + 1)) {
 	mmt = file->fa.memb_map[mt];
@@ -2000,18 +1840,6 @@ H5FD_multi_write(H5FD_t *_file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr,
     /* Clear the error stack */
     H5Eclear2(H5E_DEFAULT);
 
-    /* Get the data transfer properties */
-    if(H5P_FILE_ACCESS_DEFAULT != dxpl_id) {
-        /* Check for existence of multi VFD DXPL property in DXPL */
-        if((prop_exists = H5Pexist(dxpl_id, H5FD_MULTI_DXPL_PROP_NAME)) < 0)
-            H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTGET, "can't check for multi VFD property", -1)
-
-        /* Get the DXPL value, if it exists */
-        if(prop_exists)
-            if(H5Pget(dxpl_id, H5FD_MULTI_DXPL_PROP_NAME, &dx) < 0)
-                H5Epush_ret(func, H5E_ERR_CLS, H5E_PLIST, H5E_CANTGET, "can't get property value", -1)
-    } /* end if */
-
     /* Find the file to which this address belongs */
     for(mt = H5FD_MEM_SUPER; mt < H5FD_MEM_NTYPES; mt = (H5FD_mem_t)(mt + 1)) {
 	mmt = file->fa.memb_map[mt];
diff --git a/src/H5FDmulti.h b/src/H5FDmulti.h
index da16b0c..e819e74 100644
--- a/src/H5FDmulti.h
+++ b/src/H5FDmulti.h
@@ -34,9 +34,6 @@ H5_DLL herr_t H5Pset_fapl_multi(hid_t fapl_id, const H5FD_mem_t *memb_map,
 H5_DLL herr_t H5Pget_fapl_multi(hid_t fapl_id, H5FD_mem_t *memb_map/*out*/,
 			 hid_t *memb_fapl/*out*/, char **memb_name/*out*/,
 			 haddr_t *memb_addr/*out*/, hbool_t *relax/*out*/);
-H5_DLL herr_t H5Pset_dxpl_multi(hid_t dxpl_id, const hid_t *memb_dxpl);
-H5_DLL herr_t H5Pget_dxpl_multi(hid_t dxpl_id, hid_t *memb_dxpl/*out*/);
-
 H5_DLL herr_t H5Pset_fapl_split(hid_t fapl, const char *meta_ext,
 			 hid_t meta_plist_id, const char *raw_ext,
 			 hid_t raw_plist_id);
diff --git a/src/H5HFsection.c b/src/H5HFsection.c
index 7f5f233..7f8efbd 100644
--- a/src/H5HFsection.c
+++ b/src/H5HFsection.c
@@ -449,7 +449,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-herr_t
+static herr_t
 H5HF_sect_node_free(H5HF_free_section_t *sect, H5HF_indirect_t *iblock)
 {
     herr_t ret_value = SUCCEED;               /* Return value */
diff --git a/src/H5PL.c b/src/H5PL.c
new file mode 100644
index 0000000..07e90af
--- /dev/null
+++ b/src/H5PL.c
@@ -0,0 +1,661 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * 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 files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic document set and is     *
+ * linked from the top-level documents page.  It can also be found at        *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have access   *
+ * to either file, you may request a copy from help@hdfgroup.org.            *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/****************/
+/* Module Setup */
+/****************/
+
+/* Interface initialization */
+#define H5_INTERFACE_INIT_FUNC	H5PL__init_interface
+
+
+/***********/
+/* Headers */
+/***********/
+#include "H5private.h"		/* Generic Functions			*/
+#include "H5Eprivate.h"		/* Error handling		  	*/
+#include "H5MMprivate.h"	/* Memory management			*/
+#include "H5PLprivate.h"	/* Plugin       			*/
+#include "H5Zprivate.h"		/* Filter pipeline			*/
+
+
+/****************/
+/* Local Macros */
+/****************/
+
+#define H5PL_MAX_PATH_NUM       16
+
+/****************************/
+/* Macros for supporting 
+ * both Windows and Unix */
+/****************************/
+/* Windows support */
+#ifdef H5_HAVE_WIN32_API
+
+#define H5PL_DEFAULT_PATH       "%ALLUSERSPROFILE%/hdf5/lib/plugin"
+#define H5PL_PATH_SEPARATOR     ";"
+
+/* Handle for dynamic library */
+#define H5PL_HANDLE HINSTANCE
+
+/* Get a handle to a plugin library.  Windows: TEXT macro handles Unicode strings */
+#define H5PL_OPEN_DLIB(S) LoadLibraryEx(TEXT(S), NULL, LOAD_WITH_ALTERED_SEARCH_PATH)
+
+/* Get the address of a symbol in dynamic library */
+#define H5PL_GET_LIB_FUNC(H,N) GetProcAddress(H,N)
+
+/* Close dynamic library */
+#define H5PL_CLOSE_LIB(H) FreeLibrary(H)
+
+/* Clear error - nothing to do */
+#define H5PL_CLR_ERROR
+
+typedef const void *(__cdecl *H5PL_get_plugin_info_t)(void);
+
+/* Unix support */
+#else /* H5_HAVE_WIN32_API */
+
+#define H5PL_DEFAULT_PATH       "/usr/local/hdf5/lib/plugin"
+#define H5PL_PATH_SEPARATOR     ":"
+
+/* Handle for dynamic library */
+#define H5PL_HANDLE void *
+
+/* Get a handle to a plugin library.  Windows: TEXT macro handles Unicode strings */
+#define H5PL_OPEN_DLIB(S) dlopen(S, RTLD_NOW)
+
+/* Get the address of a symbol in dynamic library */
+#define H5PL_GET_LIB_FUNC(H,N) dlsym(H,N)
+
+/* Close dynamic library */
+#define H5PL_CLOSE_LIB(H) dlclose(H)
+
+/* Clear error */
+#define H5PL_CLR_ERROR dlerror()
+
+typedef const void *(*H5PL_get_plugin_info_t)(void);
+#endif /* H5_HAVE_WIN32_API */
+
+/* Special symbol to indicate no plugin loading */
+#define H5PL_NO_PLUGIN          "::"
+
+/******************/
+/* Local Typedefs */
+/******************/
+
+/* Type for the list of info for opened plugin libraries */
+typedef struct H5PL_table_t {
+    H5PL_type_t pl_type;			/* plugin type	     */
+    int         pl_id;                          /* ID for the plugin */
+    H5PL_HANDLE handle;			/* plugin handle     */
+} H5PL_table_t;
+
+
+/********************/
+/* Local Prototypes */
+/********************/
+
+static herr_t H5PL__init_path_table(void);
+static htri_t H5PL__find(H5PL_type_t plugin_type, int type_id, char *dir, const void **info);
+static htri_t H5PL__open(H5PL_type_t pl_type, char *libname, int plugin_id, const void **pl_info);
+static htri_t H5PL__search_table(H5PL_type_t plugin_type, int type_id, const void **info);
+static herr_t H5PL__close(H5PL_HANDLE handle);
+
+
+/*********************/
+/* Package Variables */
+/*********************/
+
+
+/*****************************/
+/* Library Private Variables */
+/*****************************/
+
+
+/*******************/
+/* Local Variables */
+/*******************/
+
+/* Table for opened plugin libraries */
+static size_t		H5PL_table_alloc_g = 0;
+static size_t		H5PL_table_used_g = 0;
+static H5PL_table_t     *H5PL_table_g = NULL;
+
+/* Table of location paths for plugin libraries */
+static char             *H5PL_path_table_g[H5PL_MAX_PATH_NUM];
+static size_t           H5PL_num_paths_g = 0;
+static hbool_t          H5PL_path_found_g = FALSE;
+
+/* Whether to preload pathnames for plugin libraries */
+static hbool_t          H5PL_no_plugin_g = FALSE;
+
+
+/*--------------------------------------------------------------------------
+NAME
+   H5PL__init_interface -- Initialize interface-specific information
+USAGE
+    herr_t H5PL__init_interface()
+RETURNS
+    Non-negative on success/Negative on failure
+DESCRIPTION
+    Initializes any interface-specific data or routines.
+
+--------------------------------------------------------------------------*/
+static herr_t
+H5PL__init_interface(void)
+{
+    char        *preload_path;
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Retrieve pathnames from HDF5_PLUGIN_PRELOAD if the user sets it
+     * to tell the library to load plugin libraries without search.
+     */
+    if(NULL != (preload_path = HDgetenv("HDF5_PLUGIN_PRELOAD"))) {
+        /* Special symbal "::" means no plugin during data reading. */
+        if(!HDstrcmp(preload_path, H5PL_NO_PLUGIN))
+            H5PL_no_plugin_g = TRUE;
+    } /* end if */
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5PL__init_interface() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5PL_no_plugin
+ *
+ * Purpose:	Quick way for filter module to query whether to load plugin 
+ *
+ * Return:	TRUE:	No plugin loading during data reading
+ *
+ * 		FALSE:	Load plugin during data reading
+ *
+ * Programmer:	Raymond Lu
+ *              20 February 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+htri_t
+H5PL_no_plugin(void)
+{
+    htri_t ret_value;
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    ret_value = (htri_t)H5PL_no_plugin_g;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5PL_no_plugin() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5PL_term_interface
+ *
+ * Purpose:	Terminate the H5PL interface: release all memory, reset all
+ *		global variables to initial values. This only happens if all
+ *		types have been destroyed from other interfaces.
+ *
+ * Return:	Success:	Positive if any action was taken that might
+ *				affect some other interface; zero otherwise.
+ *
+ * 		Failure:	Negative.
+ *
+ * Programmer:	Raymond Lu
+ *              20 February 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+H5PL_term_interface(void)
+{
+    int  i = 0;
+    
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+
+    if(H5_interface_initialize_g) {
+        size_t u;       /* Local index variable */
+
+	/* Close opened dynamic libraries */
+        for(u = 0; u < H5PL_table_used_g; u++)
+            H5PL__close((H5PL_table_g[u]).handle);
+
+	/* Free the table of dynamic libraries */
+	H5PL_table_g = (H5PL_table_t *)H5MM_xfree(H5PL_table_g);
+	H5PL_table_used_g = H5PL_table_alloc_g = 0;
+
+        /* Free the table of search paths */
+        for(u = 0; u < H5PL_num_paths_g; u++)
+            if(H5PL_path_table_g[u])
+                H5PL_path_table_g[u] = (char *)H5MM_xfree(H5PL_path_table_g[u]);
+        H5PL_num_paths_g = 0;
+        H5PL_path_found_g = FALSE;
+
+	H5_interface_initialize_g = 0;
+        i = 1;
+    } /* end if */
+
+    FUNC_LEAVE_NOAPI(i)
+} /* end H5PL_term_interface() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5PL_load
+ *
+ * Purpose:	Given the plugin type and identifier, this function searches
+ *              and/or loads a dynamic plugin library first among the already
+ *              opened libraries then in the designated location paths.
+ *
+ * Return:	Non-NULL on success/NULL on failure
+ *
+ * Programmer:	Raymond Lu
+ *              13 February 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+const void *
+H5PL_load(H5PL_type_t type, int id)
+{
+    htri_t      found;               /* Whether the plugin was found */
+    const void  *plugin_info = NULL;
+    const void  *ret_value = NULL;
+
+    FUNC_ENTER_NOAPI(NULL)
+
+    /* Initialize the location paths for dynamic libraries, if they aren't
+     * already set up.
+     */
+    if(FALSE == H5PL_path_found_g)
+        if(H5PL__init_path_table() < 0)
+            HGOTO_ERROR(H5E_PLUGIN, H5E_CANTINIT, NULL, "can't initialize search path table")
+
+    /* Search in the table of already loaded plugin libraries */
+    if((found = H5PL__search_table(type, id, &plugin_info)) < 0)
+        HGOTO_ERROR(H5E_PLUGIN, H5E_CANTGET, NULL, "search in table failed")
+
+    /* If not found, iterate through the path table to find the right dynamic library */
+    if(!found) {
+        size_t	   i;                   /* Local index variable */
+
+        for(i = 0; i < H5PL_num_paths_g; i++) {
+            if((found = H5PL__find(type, id, H5PL_path_table_g[i], &plugin_info)) < 0)
+                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTGET, NULL, "search in paths failed")
+     
+            /* Break out if found */
+            if(found) {
+                HDassert(plugin_info);
+                break;
+            } /* end if */
+        } /* end for */
+    } /* end if */
+
+    /* Check if we found the plugin */
+    if(found)
+        ret_value = plugin_info;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5PL_load() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5PL__init_path_table
+ *
+ * Purpose:	Initialize the path table.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              18 March 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5PL__init_path_table(void)
+{
+    char        *dl_path = NULL;
+    char        *origin_dl_path;
+    char        *dir;
+    herr_t      ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Retrieve paths from HDF5_PLUGIN_PATH if the user sets it
+     * or from the default paths if it isn't set.
+     */
+    origin_dl_path = HDgetenv("HDF5_PLUGIN_PATH");
+    if(NULL == origin_dl_path)
+        dl_path = HDstrdup(H5PL_DEFAULT_PATH);
+    else
+        dl_path = HDstrdup(origin_dl_path);
+    if(NULL == dl_path)
+        HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "can't allocate memory for path")
+
+    /* Put paths in the path table.  They are separated by ":" */
+    dir = HDstrtok(dl_path, H5PL_PATH_SEPARATOR);
+    while(dir) {
+        /* Check for too many directories in path */
+        if(H5PL_num_paths_g == H5PL_MAX_PATH_NUM)
+            HGOTO_ERROR(H5E_PLUGIN, H5E_NOSPACE, FAIL, "too many directories in path for table")
+        if(NULL == (H5PL_path_table_g[H5PL_num_paths_g] = HDstrdup(dir)))
+            HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "can't allocate memory for path")
+        H5PL_num_paths_g++;
+        dir = HDstrtok(NULL, H5PL_PATH_SEPARATOR);
+    } /* end while */
+
+    H5PL_path_found_g = TRUE;
+
+done:
+    if(dl_path)
+        dl_path = (char *)H5MM_xfree(dl_path);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5PL__init_path_table() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5PL__find
+ *
+ * Purpose:     Given a path, this function opens the directory and envokes
+ *              another function to go through all files to find the right 
+ *              plugin library. Two function definitions are for Unix and 
+ *              Windows.
+ *
+ * Return:	TRUE on success, 
+ *              FALSE on not found,
+ *              negative on failure
+ *
+ * Programmer:	Raymond Lu
+ *              13 February 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef H5_HAVE_WIN32_API
+static htri_t
+H5PL__find(H5PL_type_t plugin_type, int type_id, char *dir, const void **info)
+{
+    char           *pathname = NULL;
+    DIR            *dirp = NULL;
+    struct dirent  *dp;
+    htri_t         ret_value = FALSE;
+
+    FUNC_ENTER_STATIC
+
+    /* Open the directory */  
+    if(!(dirp = HDopendir(dir)))
+        HGOTO_ERROR(H5E_PLUGIN, H5E_OPENERROR, FAIL, "can't open directory")
+
+    /* Iterates through all entries in the directory to find the right plugin library */
+    while(NULL != (dp = HDreaddir(dirp))) {
+        /* The library we are looking for should be called libxxx.so... on Unix 
+         * or libxxx.xxx.dylib on Mac.
+         */ 
+        if(!HDstrncmp(dp->d_name, "lib", (size_t)3) && 
+                (HDstrstr(dp->d_name, ".so") || HDstrstr(dp->d_name, ".dylib"))) {
+            h5_stat_t   my_stat;
+            size_t      pathname_len;
+            htri_t      found_in_dir;
+
+            /* Allocate & initialize the path name */
+            pathname_len = HDstrlen(dir) + HDstrlen(dp->d_name) + 2;
+            if(NULL == (pathname = (char *)H5MM_malloc(pathname_len)))
+                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "can't allocate memory for path")
+            HDsnprintf(pathname, pathname_len, "%s/%s", dir, dp->d_name);
+
+            /* Get info for directory entry */
+            if(HDstat(pathname, &my_stat) == -1)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "can't stat file: %s", strerror(errno))
+
+            /* If it is a directory, skip it */ 
+            if(S_ISDIR(my_stat.st_mode))
+                continue;
+
+            /* Attempt to open the dynamic library as a filter library */
+            if((found_in_dir = H5PL__open(plugin_type, pathname, type_id, info)) < 0)
+                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTGET, FAIL, "search in directory failed")
+            if(found_in_dir) {
+                /* Indicate success */
+                HGOTO_DONE(TRUE)
+            } /* end if */
+            else
+                HDassert(pathname);
+                pathname = (char *)H5MM_xfree(pathname);
+        } /* end if */
+    } /* end while */
+
+done:
+    if(dirp) 
+        if(HDclosedir(dirp) < 0)
+            HDONE_ERROR(H5E_FILE, H5E_CLOSEERROR, FAIL, "can't close directory: %s", strerror(errno))
+    if(pathname) 
+        pathname = (char *)H5MM_xfree(pathname);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5PL__find() */
+#else /* H5_HAVE_WIN32_API */
+static htri_t
+H5PL__find(H5PL_type_t plugin_type, int type_id, char *dir, const void **info)
+{
+    WIN32_FIND_DATA fdFile;
+    HANDLE          hFind;
+    char           *pathname = NULL;
+    char            service[2048];
+    htri_t          ret_value = FALSE;
+
+    FUNC_ENTER_STATIC
+
+    /* Specify a file mask. *.* = We want everything! */
+    sprintf(service, "%s\/*.dll", dir);
+    if((hFind = FindFirstFile(service, &fdFile)) == INVALID_HANDLE_VALUE)
+        HGOTO_ERROR(H5E_PLUGIN, H5E_OPENERROR, FAIL, "can't open directory")
+
+    do {
+        /* Find first file will always return "."
+         * and ".." as the first two directories.
+         */
+        if(HDstrcmp(fdFile.cFileName, ".") != 0 && HDstrcmp(fdFile.cFileName, "..") != 0) {
+            size_t      pathname_len;
+            htri_t      found_in_dir;
+
+            /* Allocate & initialize the path name */
+            pathname_len = HDstrlen(dir) + HDstrlen(fdFile.cFileName) + 2;
+	    if(NULL == (pathname = (char *)H5MM_malloc(pathname_len)))
+                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTALLOC, FAIL, "can't allocate memory for path")
+            HDsnprintf(pathname, pathname_len, "%s\\%s", dir, fdFile.cFileName);
+
+            /* Is the entity a File or Folder? */
+            if(fdFile.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
+                continue;
+
+            if((found_in_dir = H5PL__open(plugin_type, pathname, type_id, info)) < 0)
+                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTGET, FAIL, "search in directory failed")
+            if(found_in_dir) {
+                /* Indicate success */
+                HGOTO_DONE(TRUE)
+            } /* end if */
+            else
+	        HDassert(pathname);
+                pathname = (char *)H5MM_xfree(pathname);
+        } /* end if */
+    } while(FindNextFile(hFind, &fdFile)); /* Find the next file. */
+
+done:
+    if(hFind) 
+        FindClose(hFind);
+    if(pathname) 
+        pathname = (char *)H5MM_xfree(pathname);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5PL__find() */
+#endif /* H5_HAVE_WIN32_API */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5PL__open
+ *
+ * Purpose:     Iterates through all files to find the right plugin library.
+ *              It loads the dynamic plugin library and keeps it on the list 
+ *              of loaded libraries. 	
+ *
+ * Return:	TRUE on success, 
+ *              FALSE on not found,
+ *              negative on failure
+ *
+ * Programmer:	Raymond Lu
+ *              13 February 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+static htri_t
+H5PL__open(H5PL_type_t pl_type, char *libname, int pl_id, const void **pl_info)
+{
+    H5PL_HANDLE    handle = NULL;
+    htri_t         ret_value = FALSE;
+
+    FUNC_ENTER_STATIC
+
+    /* There are different reasons why a library can't be open, e.g. wrong architecture.
+     * simply continue if we can't open it.
+     */
+    if(NULL == (handle = H5PL_OPEN_DLIB(libname))) {
+        H5PL_CLR_ERROR; /* clear error */
+    } /* end if */
+    else {
+        H5PL_get_plugin_info_t get_plugin_info = NULL;
+
+        /* Return a handle for the function H5PLget_plugin_info in the dynamic library.
+         * The plugin library is suppose to define this function.
+         */
+        if(NULL == (get_plugin_info = (H5PL_get_plugin_info_t)H5PL_GET_LIB_FUNC(handle, "H5PLget_plugin_info"))) {
+            if(H5PL__close(handle) < 0)
+                HGOTO_ERROR(H5E_PLUGIN, H5E_CLOSEERROR, FAIL, "can't close dynamic library")
+        } /* end if */
+        else {
+            const H5Z_class2_t *plugin_info;
+
+            /* Invoke H5PLget_plugin_info to verify this is the right library we are looking for.
+             * Move on if it isn't.
+             */
+            if(NULL == (plugin_info = (const H5Z_class2_t *)(*get_plugin_info)())) {
+                if(H5PL__close(handle) < 0)
+                    HGOTO_ERROR(H5E_PLUGIN, H5E_CLOSEERROR, FAIL, "can't close dynamic library")
+                HGOTO_ERROR(H5E_PLUGIN, H5E_CANTGET, FAIL, "can't get plugin info")
+            } /* end if */
+
+            /* Successfully found plugin library, check if it's the right one */
+            if(plugin_info->id == pl_id) {
+                /* Expand the table if it is too small */
+                if(H5PL_table_used_g >= H5PL_table_alloc_g) {
+                    size_t n = MAX(H5Z_MAX_NFILTERS, 2 * H5PL_table_alloc_g);
+                    H5PL_table_t *table = (H5PL_table_t *)H5MM_realloc(H5PL_table_g, n * sizeof(H5PL_table_t));
+
+                    if(!table)
+                        HGOTO_ERROR(H5E_RESOURCE, H5E_CANTALLOC, FAIL, "unable to extend dynamic library table")
+
+                    H5PL_table_g = table;
+                    H5PL_table_alloc_g = n;
+                } /* end if */
+
+                (H5PL_table_g[H5PL_table_used_g]).handle = handle;
+                (H5PL_table_g[H5PL_table_used_g]).pl_type = pl_type;
+                (H5PL_table_g[H5PL_table_used_g]).pl_id = plugin_info->id;
+                H5PL_table_used_g++;
+
+                /* Set the plugin info to return */
+                *pl_info = (const void *)plugin_info;
+     
+                /* Indicate success */
+                ret_value = TRUE;
+            } /* end if */
+            else
+                if(H5PL__close(handle) < 0)
+                    HGOTO_ERROR(H5E_PLUGIN, H5E_CLOSEERROR, FAIL, "can't close dynamic library")
+        } /* end if */
+    } /* end else */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5PL__open() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5PL__search_table
+ *
+ * Purpose:     Search in the list of already opened dynamic libraries
+ *              to see if the one we are looking for is already opened.
+ *
+ * Return:	TRUE on success, 
+ *              FALSE on not found,
+ *              Negative on failure
+ *
+ * Programmer:	Raymond Lu
+ *              13 February 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+static htri_t
+H5PL__search_table(H5PL_type_t plugin_type, int type_id, const void **info)
+{
+    htri_t         ret_value = FALSE;
+
+    FUNC_ENTER_STATIC
+
+    /* Search in the table of already opened dynamic libraries */
+    if(H5PL_table_used_g > 0) {
+        size_t         i;
+
+        for(i = 0; i < H5PL_table_used_g; i++) {
+            if((plugin_type == (H5PL_table_g[i]).pl_type) && (type_id == (H5PL_table_g[i]).pl_id)) {
+                H5PL_get_plugin_info_t get_plugin_info;
+                const H5Z_class2_t   *plugin_info;
+
+                if(NULL == (get_plugin_info = (H5PL_get_plugin_info_t)H5PL_GET_LIB_FUNC((H5PL_table_g[i]).handle, "H5PLget_plugin_info")))
+		    HGOTO_ERROR(H5E_DATATYPE, H5E_CANTGET, FAIL, "can't get function for H5PLget_plugin_info")
+
+	        if(NULL == (plugin_info = (const H5Z_class2_t *)(*get_plugin_info)()))
+		    HGOTO_ERROR(H5E_DATATYPE, H5E_CANTGET, FAIL, "can't get plugin info")
+
+	        *info = plugin_info;
+                HGOTO_DONE(TRUE)
+            } /* end if */
+        } /* end for */
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5PL__search_table() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5PL__close
+ *
+ * Purpose:     Closes the handle for dynamic library	
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Raymond Lu
+ *              13 February 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5PL__close(H5PL_HANDLE handle)
+{
+    FUNC_ENTER_STATIC_NOERR
+
+    H5PL_CLOSE_LIB(handle);
+   
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5PL__close() */
+
diff --git a/src/H5PLextern.h b/src/H5PLextern.h
new file mode 100644
index 0000000..943e3aa
--- /dev/null
+++ b/src/H5PLextern.h
@@ -0,0 +1,84 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * 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 files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic document set and is     *
+ * linked from the top-level documents page.  It can also be found at        *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have access   *
+ * to either file, you may request a copy from help@hdfgroup.org.            *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*
+ * Programmer:  Raymond Lu <songyulu@hdfgroup.org>
+ *              13 February 2013
+ */
+#ifndef _H5PLextern_H
+#define _H5PLextern_H
+
+/* Include HDF5 header */
+#include "hdf5.h"
+
+/*******************/
+/* Public Typedefs */
+/*******************/
+
+/* Plugin type */
+typedef enum H5PL_type_t {
+    H5PL_TYPE_ERROR        = -1,  /*error                    */
+    H5PL_TYPE_FILTER       = 0,   /*filter                   */
+    H5PL_TYPE_NONE         = 1    /*this must be last!       */
+} H5PL_type_t;
+
+
+#ifdef H5_BUILT_AS_DYNAMIC_LIB
+
+  #if defined (hdf5_EXPORTS)
+    /* hdf5 library imports from plugin */
+    #if defined (_MSC_VER)  /* MSVC Compiler Case */
+      #define H5PLUGIN_DLL __declspec(dllimport)
+    #elif (__GNUC__ >= 4)  /* GCC 4.x has support for visibility options */
+      #define H5PLUGIN_DLL __attribute__ ((visibility("default")))
+    #endif
+  #else
+    /* plugins always export */
+    #if defined (_MSC_VER)  /* MSVC Compiler Case */
+      #define H5PLUGIN_DLL __declspec(dllexport)
+    #elif (__GNUC__ >= 4)  /* GCC 4.x has support for visibility options */
+      #define H5PLUGIN_DLL __attribute__ ((visibility("default")))
+    #endif
+  #endif
+
+#elif defined(H5_BUILT_AS_STATIC_LIB)
+  #define H5PLUGIN_DLL
+#else
+
+  #if defined(H5_HAVE_WIN32_API)
+    #if defined(_HDF5DLL_)
+      #pragma warning(disable: 4273)  /* Disable the dll linkage warnings */
+      #define H5PLUGIN_DLL __declspec(dllimport)
+    #elif defined(_HDF5USEDLL_)
+      #define H5PLUGIN_DLL __declspec(dllexport)
+    #endif /* _HDF5DLL_ */
+  #else /*H5_HAVE_WIN32_API*/
+    #define H5PLUGIN_DLL
+  #endif /*H5_HAVE_WIN32_API*/
+
+#endif /* H5_BUILT_AS_xxx_LIB */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+H5PLUGIN_DLL H5PL_type_t H5PLget_plugin_type(void);
+H5PLUGIN_DLL const void *H5PLget_plugin_info(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _H5PLextern_H */
+
diff --git a/src/H5PLprivate.h b/src/H5PLprivate.h
new file mode 100644
index 0000000..b117613
--- /dev/null
+++ b/src/H5PLprivate.h
@@ -0,0 +1,53 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * 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 files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic document set and is     *
+ * linked from the top-level documents page.  It can also be found at        *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have access   *
+ * to either file, you may request a copy from help@hdfgroup.org.            *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/* Programmer:  Raymond Lu <songyulu@hdfgroup.org>
+ *              13 February 2013
+ */
+
+#ifndef _H5PLprivate_H
+#define _H5PLprivate_H
+
+/* Include package's "external" header */
+#include "H5PLextern.h"
+
+/* Private headers needed by this file */
+#include "H5private.h"          /* Generic Functions                    */
+
+
+/**************************/
+/* Library Private Macros */
+/**************************/
+
+
+/****************************/
+/* Library Private Typedefs */
+/****************************/
+
+
+/*****************************/
+/* Library-private Variables */
+/*****************************/
+
+
+/***************************************/
+/* Library-private Function Prototypes */
+/***************************************/
+
+/* Internal API routines */
+H5_DLL const void *H5PL_load(H5PL_type_t plugin_type, int type_id);
+H5_DLL htri_t H5PL_no_plugin(void);
+
+#endif /* _H5PLprivate_H */
+
diff --git a/src/H5Pfapl.c b/src/H5Pfapl.c
index 4faed4f..befec84 100644
--- a/src/H5Pfapl.c
+++ b/src/H5Pfapl.c
@@ -2267,7 +2267,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-herr_t
+static herr_t
 H5P_file_image_info_del(hid_t UNUSED prop_id, const char UNUSED *name, size_t UNUSED size, void *value)
 {
     H5FD_file_image_info_t info;        /* Image info struct */
@@ -2321,7 +2321,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-herr_t
+static herr_t
 H5P_file_image_info_copy(const char UNUSED *name, size_t UNUSED size, void *value)
 {
     herr_t ret_value = SUCCEED;         /* Return value */
@@ -2396,7 +2396,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-herr_t
+static herr_t
 H5P_file_image_info_close(const char UNUSED *name, size_t UNUSED size, void *value)
 {
     herr_t ret_value = SUCCEED;         /* Return value */
diff --git a/src/H5Pocpl.c b/src/H5Pocpl.c
index d8ddfee..880b46a 100644
--- a/src/H5Pocpl.c
+++ b/src/H5Pocpl.c
@@ -40,6 +40,8 @@
 #include "H5MMprivate.h"	/* Memory management			*/
 #include "H5Opkg.h"             /* Object headers			*/
 #include "H5Ppkg.h"		/* Property lists		  	*/
+#include "H5PLprivate.h"	/* Dynamic plugin			*/
+#include "H5Zprivate.h"	        /* Filter pipeline			*/
 
 
 /****************/
@@ -90,6 +92,9 @@ static herr_t H5P__ocrt_pipeline_enc(const void *value, void **_pp, size_t *size
 static herr_t H5P__ocrt_pipeline_dec(const void **_pp, void *value);
 static int H5P__ocrt_pipeline_cmp(const void *value1, const void *value2, size_t size);
 
+/* Local routines */
+static herr_t H5P__set_filter(H5P_genplist_t *plist, H5Z_filter_t filter, 
+    unsigned int flags, size_t cd_nelmts, const unsigned int cd_values[/*cd_nelmts*/]);
 
 /*********************/
 /* Package Variables */
@@ -747,7 +752,6 @@ H5Pset_filter(hid_t plist_id, H5Z_filter_t filter, unsigned int flags,
 	       size_t cd_nelmts, const unsigned int cd_values[/*cd_nelmts*/])
 {
     H5P_genplist_t  *plist;             /* Property list */
-    H5O_pline_t     pline;              /* Filter pipeline */
     herr_t          ret_value=SUCCEED;  /* return value */
 
     FUNC_ENTER_API(FAIL)
@@ -765,6 +769,74 @@ H5Pset_filter(hid_t plist_id, H5Z_filter_t filter, unsigned int flags,
     if(NULL == (plist = H5P_object_verify(plist_id, H5P_OBJECT_CREATE)))
         HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID")
 
+    /* Call the private function */
+    if(H5P__set_filter(plist, filter, flags, cd_nelmts, cd_values) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "failed to call private function")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Pset_filter() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5P__set_filter
+ *
+ * Purpose:	Adds the specified FILTER and corresponding properties to the
+ *		end of the data or link output filter pipeline
+ *		depending on whether PLIST is a dataset creation or group
+ *		creation property list.  The FLAGS argument specifies certain
+ *		general properties of the filter and is documented below.
+ *		The CD_VALUES is an array of CD_NELMTS integers which are
+ *		auxiliary data for the filter.  The integer vlues will be
+ *		stored in the dataset object header as part of the filter
+ *		information.
+ *
+ * 		The FLAGS argument is a bit vector of the following fields:
+ *
+ * 		H5Z_FLAG_OPTIONAL(0x0001)
+ *		If this bit is set then the filter is optional.  If the
+ *		filter fails during an H5Dwrite() operation then the filter
+ *		is just excluded from the pipeline for the chunk for which it
+ *		failed; the filter will not participate in the pipeline
+ *		during an H5Dread() of the chunk.  If this bit is clear and
+ *		the filter fails then the entire I/O operation fails.
+ *		If this bit is set but encoding is disabled for a filter,
+ *		attempting to write will generate an error.
+ *
+ *              If the filter is not registered, this function tries to load 
+ *              it dynamically during run time.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Robb Matzke
+ *              Wednesday, April 15, 1998
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5P__set_filter(H5P_genplist_t *plist, H5Z_filter_t filter, unsigned int flags,
+	       size_t cd_nelmts, const unsigned int cd_values[/*cd_nelmts*/])
+{
+    H5O_pline_t     pline;                  /* Filter pipeline */
+    htri_t          filter_avail;           /* Filter availability */
+    herr_t          ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Check if filter is already available */
+    if((filter_avail = H5Z_filter_avail(filter)) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't check filter availability")
+
+    /* If filter is not available, try to dynamically load it */
+    if(!filter_avail) {
+        const H5Z_class2_t *filter_info;
+
+        if(NULL == (filter_info = (const H5Z_class2_t *)H5PL_load(H5PL_TYPE_FILTER, (int)filter)))
+            HGOTO_ERROR(H5E_PLINE, H5E_CANTLOAD, FAIL, "failed to load dynamically loaded plugin")
+        if(H5Z_register(filter_info) < 0)
+	    HGOTO_ERROR(H5E_PLINE, H5E_CANTINIT, FAIL, "unable to register filter")
+    } /* end if */
+
     /* Get the pipeline property to append to */
     if(H5P_get(plist, H5O_CRT_PIPELINE_NAME, &pline) < 0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get pipeline")
@@ -778,8 +850,8 @@ H5Pset_filter(hid_t plist_id, H5Z_filter_t filter, unsigned int flags,
         HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set pipeline")
 
 done:
-    FUNC_LEAVE_API(ret_value)
-} /* end H5Pset_filter() */
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5P__set_filter() */
 
 
 /*-------------------------------------------------------------------------
diff --git a/src/H5Tconv.c b/src/H5Tconv.c
index 5ecf864..b732817 100644
--- a/src/H5Tconv.c
+++ b/src/H5Tconv.c
@@ -3014,17 +3014,17 @@ H5T__conv_vlen(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, size_t nelmts,
 {
     H5T_vlen_alloc_info_t _vl_alloc_info;       /* VL allocation info buffer */
     H5T_vlen_alloc_info_t *vl_alloc_info = &_vl_alloc_info;   /* VL allocation info */
-    H5T_path_t	*tpath;			/* Type conversion path		     */
+    H5T_path_t	*tpath = NULL;		/* Type conversion path		     */
     hbool_t     noop_conv = FALSE;      /* Flag to indicate a noop conversion */
     hbool_t     write_to_file = FALSE;  /* Flag to indicate writing to file */
     hbool_t     parent_is_vlen;         /* Flag to indicate parent is vlen datatyp */
     hid_t   	tsrc_id = -1, tdst_id = -1;/*temporary type atoms	     */
-    H5T_t	*src;			/*source datatype		     */
-    H5T_t	*dst;			/*destination datatype		     */
+    H5T_t	*src = NULL;		/*source datatype		     */
+    H5T_t	*dst = NULL;		/*destination datatype		     */
     H5HG_t	bg_hobjid, parent_hobjid;
-    uint8_t	*s;		        /*source buffer			*/
-    uint8_t	*d;		        /*destination buffer		*/
-    uint8_t	*b;		        /*background buffer		*/
+    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 */
@@ -3120,7 +3120,7 @@ H5T__conv_vlen(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, size_t nelmts,
             if(tpath->cdata.need_bkg || parent_is_vlen) {
                 /* Set up initial background buffer */
                 tmp_buf_size = MAX(src_base_size, dst_base_size);
-                if(NULL == (tmp_buf = H5FL_BLK_MALLOC(vlen_seq,tmp_buf_size)))
+                if(NULL == (tmp_buf = H5FL_BLK_CALLOC(vlen_seq,tmp_buf_size)))
                     HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for type conversion")
             } /* end if */
 
@@ -3200,7 +3200,7 @@ H5T__conv_vlen(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, size_t nelmts,
                              */
 			    if(!seq_len && !conv_buf) {
                                 conv_buf_size = ((1 / H5T_VLEN_MIN_CONF_BUF_SIZE) + 1) * H5T_VLEN_MIN_CONF_BUF_SIZE;
-                                if(NULL == (conv_buf = H5FL_BLK_MALLOC(vlen_seq, conv_buf_size)))
+                                if(NULL == (conv_buf = H5FL_BLK_CALLOC(vlen_seq, conv_buf_size)))
                                     HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for type conversion")
 			    }
                             else if(conv_buf_size < MAX(src_size, dst_size)) {
@@ -3208,6 +3208,7 @@ H5T__conv_vlen(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, size_t nelmts,
                                 conv_buf_size = ((MAX(src_size, dst_size) / H5T_VLEN_MIN_CONF_BUF_SIZE) + 1) * H5T_VLEN_MIN_CONF_BUF_SIZE;
                                 if(NULL == (conv_buf = H5FL_BLK_REALLOC(vlen_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 */
 
                             /* Read in VL sequence */
@@ -3223,6 +3224,7 @@ H5T__conv_vlen(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, size_t nelmts,
                                 tmp_buf_size = conv_buf_size;
                                 if(NULL == (tmp_buf = H5FL_BLK_REALLOC(vlen_seq, tmp_buf, tmp_buf_size)))
                                     HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for type conversion")
+                                HDmemset(tmp_buf, 0, tmp_buf_size);
                             } /* end if */
 
                             /* If we are writing and there is a nested VL type, read
@@ -3236,6 +3238,7 @@ H5T__conv_vlen(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, size_t nelmts,
                                         tmp_buf_size = (bg_seq_len * MAX(src_base_size, dst_base_size));
                                         if(NULL == (tmp_buf = H5FL_BLK_REALLOC(vlen_seq, tmp_buf, tmp_buf_size)))
                                             HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for type conversion")
+                                        HDmemset(tmp_buf, 0, tmp_buf_size);
                                     } /* end if */
                                     H5F_addr_decode(dst->shared->u.vlen.f, (const uint8_t **)&tmp, &(bg_hobjid.addr));
                                     INT32DECODE(tmp, bg_hobjid.idx);
diff --git a/src/H5Z.c b/src/H5Z.c
index 3bb3a44..9f8b59d 100644
--- a/src/H5Z.c
+++ b/src/H5Z.c
@@ -26,6 +26,7 @@
 #include "H5MMprivate.h"	/* Memory management			*/
 #include "H5Oprivate.h"		/* Object headers		  	*/
 #include "H5Pprivate.h"         /* Property lists                       */
+#include "H5PLprivate.h"        /* Plugins                              */
 #include "H5Sprivate.h"		/* Dataspace functions			*/
 #include "H5Zpkg.h"		/* Data filters				*/
 
@@ -450,7 +451,6 @@ done:
 htri_t
 H5Zfilter_avail(H5Z_filter_t id)
 {
-    size_t i;                   /* Local index variable */
     htri_t ret_value=FALSE;     /* Return value */
 
     FUNC_ENTER_API(FAIL)
@@ -459,13 +459,9 @@ H5Zfilter_avail(H5Z_filter_t id)
     /* Check args */
     if(id<0 || id>H5Z_FILTER_MAX)
         HGOTO_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL, "invalid filter identification number")
-
-    /* Is the filter already registered? */
-    for(i=0; i<H5Z_table_used_g; i++)
-	if(H5Z_table_g[i].id==id) {
-            ret_value=TRUE;
-            break;
-        } /* end if */
+ 
+    if((ret_value = H5Z_filter_avail(id)) < 0)
+	HGOTO_ERROR(H5E_PLINE, H5E_NOTFOUND, FAIL, "unable to check the availability of the filter")
 
 done:
     FUNC_LEAVE_API(ret_value)
@@ -473,6 +469,36 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5Z_filter_avail
+ *
+ * Purpose:	Private function to check if a filter is available
+ *
+ * Return:	Non-negative (TRUE/FALSE) on success/Negative on failure
+ *
+ * Programmer:	Raymond Lu
+ *              13 February 2013
+ *
+ *-------------------------------------------------------------------------
+ */
+htri_t
+H5Z_filter_avail(H5Z_filter_t id)
+{
+    size_t i;                   /* Local index variable */
+    htri_t ret_value = FALSE;   /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Is the filter already registered? */
+    for(i = 0; i < H5Z_table_used_g; i++)
+	if(H5Z_table_g[i].id == id)
+	    HGOTO_DONE(TRUE)
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5Z_filter_avail() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5Z_prelude_callback
  *
  * Purpose:	Makes a dataset creation "prelude" callback for the "can_apply"
@@ -1088,16 +1114,45 @@ H5Z_pipeline(const H5O_pline_t *pline, unsigned flags,
 		failed |= (unsigned)1 << idx;
 		continue;/*filter excluded*/
 	    }
-	    if ((fclass_idx=H5Z_find_idx(pline->filter[idx].id))<0) {
-                /* Print out the filter name to give more info.  But the name is optional for 
-                 * the filter */
-                if(pline->filter[idx].name)
-		    HGOTO_ERROR(H5E_PLINE, H5E_READERROR, FAIL, "required filter '%s' is not registered", 
-                            pline->filter[idx].name)
-                else
-		    HGOTO_ERROR(H5E_PLINE, H5E_READERROR, FAIL, "required filter (name unavailable) is not registered")
 
-	    }
+            /* If the filter isn't registered and the application doesn't 
+             * indicate no plugin through HDF5_PRELOAD_PLUG (using the symbol "::"), 
+             * try to load it dynamically and register it.  Otherwise, return failure
+             */
+	    if((fclass_idx = H5Z_find_idx(pline->filter[idx].id)) < 0) {
+                hbool_t issue_error = FALSE;
+
+                /* Check for "no plugins" indicated" */
+	        if(H5PL_no_plugin())
+                    issue_error = TRUE;
+                else {
+                    const H5Z_class2_t    *filter_info;
+
+                    /* Try loading the filter */
+                    if(NULL != (filter_info = (const H5Z_class2_t *)H5PL_load(H5PL_TYPE_FILTER, (int)(pline->filter[idx].id)))) {
+                        /* Register the filter we loaded */
+                        if(H5Z_register(filter_info) < 0)
+                            HGOTO_ERROR(H5E_PLINE, H5E_CANTINIT, FAIL, "unable to register filter")
+
+                        /* Search in the table of registered filters again to find the dynamic filter just loaded and registered */ 
+                        if((fclass_idx = H5Z_find_idx(pline->filter[idx].id)) < 0)
+                            issue_error = TRUE;
+                    } /* end if */
+                    else
+                        issue_error = TRUE;
+                } /* end else */
+
+                /* Check for error */
+                if(issue_error) {
+                    /* Print out the filter name to give more info.  But the name is optional for 
+                     * the filter */
+                    if(pline->filter[idx].name)
+                        HGOTO_ERROR(H5E_PLINE, H5E_READERROR, FAIL, "required filter '%s' is not registered", pline->filter[idx].name)
+                    else
+                        HGOTO_ERROR(H5E_PLINE, H5E_READERROR, FAIL, "required filter (name unavailable) is not registered")
+                } /* end if */
+            } /* end if */
+
             fclass=&H5Z_table_g[fclass_idx];
 #ifdef H5Z_DEBUG
             fstats=&H5Z_stat_table_g[fclass_idx];
diff --git a/src/H5Zprivate.h b/src/H5Zprivate.h
index c1528b3..f53b50c 100644
--- a/src/H5Zprivate.h
+++ b/src/H5Zprivate.h
@@ -92,6 +92,7 @@ H5_DLL herr_t H5Z_set_local_direct(const struct H5O_pline_t *pline);
 H5_DLL H5Z_filter_info_t *H5Z_filter_info(const struct H5O_pline_t *pline,
         H5Z_filter_t filter);
 H5_DLL htri_t H5Z_all_filters_avail(const struct H5O_pline_t *pline);
+H5_DLL htri_t H5Z_filter_avail(H5Z_filter_t id);
 H5_DLL herr_t H5Z_delete(struct H5O_pline_t *pline, H5Z_filter_t filter);
 
 /* Data Transform Functions */
diff --git a/src/H5Zpublic.h b/src/H5Zpublic.h
index 5d9b5ed..8daa5f4 100644
--- a/src/H5Zpublic.h
+++ b/src/H5Zpublic.h
@@ -42,6 +42,7 @@ typedef int H5Z_filter_t;
 #define H5Z_FILTER_NBIT         5       /*nbit compression              */
 #define H5Z_FILTER_SCALEOFFSET  6       /*scale+offset compression      */
 #define H5Z_FILTER_RESERVED     256	/*filter ids below this value are reserved for library use */
+
 #define H5Z_FILTER_MAX		65535	/*maximum filter id		*/
 
 /* General macros */
diff --git a/src/H5config.h.in b/src/H5config.h.in
index 0308b38..fc41c5a 100644
--- a/src/H5config.h.in
+++ b/src/H5config.h.in
@@ -87,6 +87,9 @@
 /* Define if the direct I/O virtual file driver should be compiled */
 #undef HAVE_DIRECT
 
+/* Define to 1 if you have the <dirent.h> header file. */
+#undef HAVE_DIRENT_H
+
 /* Define to 1 if you have the <dlfcn.h> header file. */
 #undef HAVE_DLFCN_H
 
@@ -187,6 +190,9 @@
 /* Define to 1 if you have the <io.h> header file. */
 #undef HAVE_IO_H
 
+/* Define to 1 if you have the `dl' library (-ldl). */
+#undef HAVE_LIBDL
+
 /* Define to 1 if you have the `dmalloc' library (-ldmalloc). */
 #undef HAVE_LIBDMALLOC
 
diff --git a/src/H5err.txt b/src/H5err.txt
index ab3277f..5a38cdf 100644
--- a/src/H5err.txt
+++ b/src/H5err.txt
@@ -76,6 +76,7 @@ MAJOR, H5E_FSPACE, Free Space Manager
 MAJOR, H5E_SOHM, Shared Object Header Messages
 MAJOR, H5E_EARRAY, Extensible Array
 MAJOR, H5E_FARRAY, Fixed Array
+MAJOR, H5E_PLUGIN, Plugin for dynamically loaded library
 MAJOR, H5E_NONE_MAJOR, No error
 
 # Sections (for grouping minor errors)
@@ -98,6 +99,7 @@ SECTION, HEAP, Heap errors
 SECTION, FSPACE, Free space errors
 SECTION, PIPELINE, I/O pipeline errors
 SECTION, SYSTEM, System level errors
+SECTION, PLUGIN, Plugin errors
 SECTION, NONE, No error
 
 # Minor errors
@@ -258,5 +260,8 @@ MINOR, PIPELINE, H5E_CANTFILTER, Filter operation failed
 # System level errors
 MINOR, SYSTEM, H5E_SYSERRSTR, System error message
 
+# Plugin errors
+MINOR, PLUGIN, H5E_OPENERROR, Can't open directory or file
+
 # No error, for backward compatibility */
 MINOR, NONE, H5E_NONE_MINOR, No error
diff --git a/src/H5private.h b/src/H5private.h
index 711cea8..c2ef54a 100644
--- a/src/H5private.h
+++ b/src/H5private.h
@@ -149,6 +149,17 @@
 #   include <io.h>
 #endif
 
+/*
+ * Dynamic library handling.  These are needed for dynamically loading I/O
+ * filters and VFDs.
+ */
+#ifdef H5_HAVE_DLFCN_H
+#include <dlfcn.h>
+#endif
+#ifdef H5_HAVE_DIRENT_H
+#include <dirent.h>
+#endif
+
 
 #ifdef H5_HAVE_WIN32_API
 /* The following two defines must be before any windows headers are included */
@@ -2375,6 +2386,7 @@ H5_DLL int H5G_term_interface(void);
 H5_DLL int H5I_term_interface(void);
 H5_DLL int H5L_term_interface(void);
 H5_DLL int H5P_term_interface(void);
+H5_DLL int H5PL_term_interface(void);
 H5_DLL int H5R_term_interface(void);
 H5_DLL int H5S_term_interface(void);
 H5_DLL int H5T_term_interface(void);
diff --git a/src/H5public.h b/src/H5public.h
index 0a4e9c0..7eb291f 100644
--- a/src/H5public.h
+++ b/src/H5public.h
@@ -75,10 +75,10 @@ extern "C" {
 /* Version numbers */
 #define H5_VERS_MAJOR	1	/* For major interface/format changes  	     */
 #define H5_VERS_MINOR	9	/* For minor interface/format changes  	     */
-#define H5_VERS_RELEASE	148	/* For tweaks, bug-fixes, or development     */
+#define H5_VERS_RELEASE	149	/* For tweaks, bug-fixes, or development     */
 #define H5_VERS_SUBRELEASE "FA_a5"	/* For pre-releases like snap0       */
 				/* Empty string for real releases.           */
-#define H5_VERS_INFO    "HDF5 library version: 1.9.148-FA_a5"      /* Full version string */
+#define H5_VERS_INFO    "HDF5 library version: 1.9.149-FA_a5"      /* Full version string */
 
 #define H5check()	H5check_version(H5_VERS_MAJOR,H5_VERS_MINOR,	      \
 				        H5_VERS_RELEASE)
diff --git a/src/Makefile.am b/src/Makefile.am
index 4ec1015..c910714 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -94,6 +94,7 @@ libhdf5_la_SOURCES= H5.c H5checksum.c H5dbg.c H5system.c H5timer.c H5trace.c \
         H5Pfapl.c H5Pfcpl.c H5Pfmpl.c \
         H5Pgcpl.c H5Pint.c \
         H5Plapl.c H5Plcpl.c H5Pocpl.c H5Pocpypl.c H5Pstrcpl.c H5Ptest.c \
+        H5PL.c \
         H5R.c H5Rdeprec.c \
         H5RC.c \
         H5RS.c \
@@ -121,7 +122,9 @@ include_HEADERS = hdf5.h H5api_adpt.h H5overflow.h H5pubconf.h H5public.h H5vers
 	H5FDfamily.h H5FDlog.h H5FDmpi.h H5FDmpio.h H5FDmpiposix.h              \
         H5FDmulti.h H5FDsec2.h  H5FDstdio.h \
         H5Gpublic.h  H5Ipublic.h H5Lpublic.h \
-        H5MMpublic.h H5Opublic.h H5Ppublic.h H5Rpublic.h H5Spublic.h \
+        H5MMpublic.h H5Opublic.h H5Ppublic.h \
+        H5PLextern.h \
+        H5Rpublic.h H5Spublic.h \
         H5Tpublic.h H5Zpublic.h
 
 # install libhdf5.settings in lib directory
diff --git a/src/Makefile.in b/src/Makefile.in
index db1d143..c2d29f9 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -163,9 +163,9 @@ am_libhdf5_la_OBJECTS = H5.lo H5checksum.lo H5dbg.lo H5system.lo \
 	H5Pacpl.lo H5Pdapl.lo H5Pdcpl.lo H5Pdeprec.lo H5Pdxpl.lo \
 	H5Pencdec.lo H5Pfapl.lo H5Pfcpl.lo H5Pfmpl.lo H5Pgcpl.lo \
 	H5Pint.lo H5Plapl.lo H5Plcpl.lo H5Pocpl.lo H5Pocpypl.lo \
-	H5Pstrcpl.lo H5Ptest.lo H5R.lo H5Rdeprec.lo H5RC.lo H5RS.lo \
-	H5S.lo H5Sall.lo H5Sdbg.lo H5Shyper.lo H5Smpio.lo H5Snone.lo \
-	H5Spoint.lo H5Sselect.lo H5Stest.lo H5SL.lo H5SM.lo \
+	H5Pstrcpl.lo H5Ptest.lo H5PL.lo H5R.lo H5Rdeprec.lo H5RC.lo \
+	H5RS.lo H5S.lo H5Sall.lo H5Sdbg.lo H5Shyper.lo H5Smpio.lo \
+	H5Snone.lo H5Spoint.lo H5Sselect.lo H5Stest.lo H5SL.lo H5SM.lo \
 	H5SMbtree2.lo H5SMcache.lo H5SMmessage.lo H5SMtest.lo H5ST.lo \
 	H5T.lo H5Tarray.lo H5Tbit.lo H5Tcommit.lo H5Tcompound.lo \
 	H5Tconv.lo H5Tcset.lo H5Tdbg.lo H5Tdeprec.lo H5Tenum.lo \
@@ -525,7 +525,7 @@ CHECK_CLEANFILES = *.chkexe *.chklog *.clog
 # Add libtool shared library version numbers to the HDF5 library
 # See libtool versioning documentation online.
 LT_VERS_INTERFACE = 6
-LT_VERS_REVISION = 138
+LT_VERS_REVISION = 139
 LT_VERS_AGE = 0
 H5detect_CFLAGS = -g $(AM_CFLAGS)
 
@@ -594,6 +594,7 @@ libhdf5_la_SOURCES = H5.c H5checksum.c H5dbg.c H5system.c H5timer.c H5trace.c \
         H5Pfapl.c H5Pfcpl.c H5Pfmpl.c \
         H5Pgcpl.c H5Pint.c \
         H5Plapl.c H5Plcpl.c H5Pocpl.c H5Pocpypl.c H5Pstrcpl.c H5Ptest.c \
+        H5PL.c \
         H5R.c H5Rdeprec.c \
         H5RC.c \
         H5RS.c \
@@ -621,7 +622,9 @@ include_HEADERS = hdf5.h H5api_adpt.h H5overflow.h H5pubconf.h H5public.h H5vers
 	H5FDfamily.h H5FDlog.h H5FDmpi.h H5FDmpio.h H5FDmpiposix.h              \
         H5FDmulti.h H5FDsec2.h  H5FDstdio.h \
         H5Gpublic.h  H5Ipublic.h H5Lpublic.h \
-        H5MMpublic.h H5Opublic.h H5Ppublic.h H5Rpublic.h H5Spublic.h \
+        H5MMpublic.h H5Opublic.h H5Ppublic.h \
+        H5PLextern.h \
+        H5Rpublic.h H5Spublic.h \
         H5Tpublic.h H5Zpublic.h
 
 
@@ -955,6 +958,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Otest.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Ounknown.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5P.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5PL.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Pacpl.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Pdapl.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Pdcpl.Plo@am__quote@