Much normalization with develop (#701)

* Brings CMake updates from develop

* Brings reduction in pedantic casts from develop

* Purges UFAIL from the library (#637)

* Committing clang-format changes

* Purges UFAIL from the library

* H5HL_insert change requested in PR

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

* Removes gratuitous (double)x.yF casts (#632)

* Committing clang-format changes

* Removes gratuitous (double)x.yF casts

* Committing clang-format changes

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

* Committing clang-format changes

* Cleans up a const warning left over from previous constification (#633)

* Committing clang-format changes

* Adds consts to a few global variables

* Cleans up a const warning left over from previous constification

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

* Formatted source

* Bring over some VOL registration changes

* VOL cleanup

* H5VL_request_status_t substitutions

* H5F.c cleanup

* Minor API tweaks from develop

* Moves H5G package init/teardown to H5Gint.c

* H5G cleanup

* H5M cleanup

* H5SM cleanup

* H5T cleanup

* H5R cleanup

* H5Lpublic.h cleanup

* H5L cleanup

* H5O cleanup

* H5A, H5CS, and H5AC cleanup

* Moved H5A init/teardown code to H5Aint.c

* Moves H5D I/O functions to H5D.c

* H5D cleanup

* Misc minor cleanup

* H5P close cleanup

* H5Tpublic.h cleanup

* Fixes err_compat test

* H5PLpublic.h cleanup

* Updates H5Ppublic.h

* H5Fpublic.h updates

* H5A.c cleanup

* Brings over H5Aexists and related changes

* Brings CMake shell testing changes from develop

* Close callback changes

* H5R and H5Tcommit normalization

* err_compat test works now

* H5O tweaks

* Updates VOL registration code

* Brings over H5VL_create_object

* H5Tconv.c reformatting

* H5T.c tweaks

* Brings datatype and reference updates from develop

* Brings VOL plugin loading changes from develop

* Brings event sets from develop

* Brings async functions over

* Tools changes

* Brings over many tools changes from develop

* Brings VOL flags from develop

* Fixes h5dump double/float tests

* Updates h5repack tests

* Brings h5diff test changes from develop

* Last h5dump changes

* Brings test changes from develop

* Committing clang-format changes

* Tidied h5_testing()

* Brings chunk iteration code + misc from develop

* Updates vds test

* Enables external link parallel test

* Brings updated property lists from develop

* H5G changes from develop

* H5MF cleanup

* Brings vfd_swmr test back into CMake

* Updates threadsafe test

* Updates plist test

* Brings recent changes from develop

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

15 files changed, 195 insertions, 41 deletions

diff --git a/tools/test/h5diff/CMakeTests.cmake b/tools/test/h5diff/CMakeTests.cmake
index 5d944b0..9c27076 100644
--- a/tools/test/h5diff/CMakeTests.cmake
+++ b/tools/test/h5diff/CMakeTests.cmake
@@ -293,6 +293,7 @@
       ${HDF5_TOOLS_TEST_H5DIFF_SOURCE_DIR}/testfiles/h5diff_80.txt
       ${HDF5_TOOLS_TEST_H5DIFF_SOURCE_DIR}/testfiles/h5diff_800.txt
       ${HDF5_TOOLS_TEST_H5DIFF_SOURCE_DIR}/testfiles/h5diff_801.txt
+      ${HDF5_TOOLS_TEST_H5DIFF_SOURCE_DIR}/testfiles/h5diff_830.txt
       ${HDF5_TOOLS_TEST_H5DIFF_SOURCE_DIR}/testfiles/h5diff_90.txt
       ${HDF5_TOOLS_TEST_H5DIFF_SOURCE_DIR}/testfiles/h5diff_8625.txt
       ${HDF5_TOOLS_TEST_H5DIFF_SOURCE_DIR}/testfiles/h5diff_8639.txt
@@ -919,6 +920,8 @@
           h5diff_800.out.err
           h5diff_801.out
           h5diff_801.out.err
+          h5diff_830.out
+          h5diff_830.out.err
           h5diff_8625.out
           h5diff_8625.out.err
           h5diff_8639.out
@@ -1544,6 +1547,11 @@ ADD_H5_TEST (h5diff_800 1 -v ${FILE7} ${FILE8} /g1/array /g1/array)
 ADD_H5_TEST (h5diff_801 1 -v ${FILE7} ${FILE8A} /g1/array /g1/array)
 
 # ##############################################################################
+# # dataset subsets
+# ##############################################################################
+ADD_H5_TEST (h5diff_830 1 --enable-error-stack -v ${FILE7} ${FILE8} /g1/array3D[0,0,0;2,2,1;2,2,2;] /g1/array3D[0,0,0;2,2,1;2,2,2;])
+
+# ##############################################################################
 # # VDS tests
 # ##############################################################################
 ADD_H5_TEST (h5diff_v1 0 -v ${FILEV1} ${FILEV2})
diff --git a/tools/test/h5diff/dynlib_diff.c b/tools/test/h5diff/dynlib_diff.c
index 4568ca1..433522d 100644
--- a/tools/test/h5diff/dynlib_diff.c
+++ b/tools/test/h5diff/dynlib_diff.c
@@ -25,13 +25,13 @@ static size_t H5Z_filter_dynlibud(unsigned int flags, size_t cd_nelmts, const un
 
 /* This message derives from H5Z */
 const H5Z_class2_t H5Z_DYNLIBUD[1] = {{
-    H5Z_CLASS_T_VERS,                /* H5Z_class_t version             */
-    H5Z_FILTER_DYNLIBUD,             /* Filter id number        */
-    1, 1,                            /* Encoding and decoding enabled   */
-    "dynlibud",                      /* Filter name for debugging    */
-    NULL,                            /* The "can apply" callback        */
-    NULL,                            /* The "set local" callback        */
-    (H5Z_func_t)H5Z_filter_dynlibud, /* The actual filter function    */
+    H5Z_CLASS_T_VERS,    /* H5Z_class_t version             */
+    H5Z_FILTER_DYNLIBUD, /* Filter id number        */
+    1, 1,                /* Encoding and decoding enabled   */
+    "dynlibud",          /* Filter name for debugging    */
+    NULL,                /* The "can apply" callback        */
+    NULL,                /* The "set local" callback        */
+    H5Z_filter_dynlibud, /* The actual filter function    */
 }};
 
 H5PL_type_t
@@ -70,7 +70,7 @@ H5Z_filter_dynlibud(unsigned int flags, size_t cd_nelmts, const unsigned int *cd
         return (0);
 
     /* Assignment to eliminate unused parameter warning. */
-    cd_values = cd_values;
+    (void)cd_values;
 
     if (flags & H5Z_FLAG_REVERSE) { /*read*/
         /* Subtract the original value with MULTIPLIER */
diff --git a/tools/test/h5diff/h5diffgentest.c b/tools/test/h5diff/h5diffgentest.c
index 698bd74..f03254e 100644
--- a/tools/test/h5diff/h5diffgentest.c
+++ b/tools/test/h5diff/h5diffgentest.c
@@ -31,7 +31,7 @@ size_t H5TOOLS_MALLOCSIZE = (128 * 1024 * 1024);
  *
  * Purpose: generate files for h5diff testing
  *
- * Programmer: Pedro Vicente, pvn@ncsa.uiuc.edu
+ * Programmer: Pedro Vicente
  *
  * Date: November 12, 2003
  *
@@ -465,15 +465,15 @@ test_basic(const char *fname1, const char *fname2, const char *fname3)
         float data15[6];
         float data16[6];
 
-        data15[0] = (float)HDsqrt(-1.0F);
+        data15[0] = (float)HDsqrt(-1.0);
         data15[1] = 1.0F;
-        data15[2] = (float)HDsqrt(-1.0F);
+        data15[2] = (float)HDsqrt(-1.0);
         data15[3] = 1.0F;
         data15[4] = 1.0F;
         data15[5] = 1.0F;
 
-        data16[0] = (float)HDsqrt(-1.0F);
-        data16[1] = (float)HDsqrt(-1.0F);
+        data16[0] = (float)HDsqrt(-1.0);
+        data16[1] = (float)HDsqrt(-1.0);
         data16[2] = 1.0F;
         data16[3] = 1.0F;
         data16[4] = 1.0F;
@@ -492,19 +492,19 @@ test_basic(const char *fname1, const char *fname2, const char *fname3)
         double data17[6];
         double data18[6];
 
-        data17[0] = HDsqrt(-1.0F);
-        data17[1] = 1.0F;
-        data17[2] = HDsqrt(-1.0F);
-        data17[3] = 1.0F;
-        data17[4] = 1.0F;
-        data17[5] = 1.0F;
+        data17[0] = HDsqrt(-1.0);
+        data17[1] = 1.0;
+        data17[2] = HDsqrt(-1.0);
+        data17[3] = 1.0;
+        data17[4] = 1.0;
+        data17[5] = 1.0;
 
-        data18[0] = HDsqrt(-1.0F);
-        data18[1] = HDsqrt(-10000.0F);
-        data18[2] = 1.0F;
-        data18[3] = 1.0F;
-        data18[4] = 1.0F;
-        data18[5] = 1.0F;
+        data18[0] = HDsqrt(-1.0);
+        data18[1] = HDsqrt(-10000.0);
+        data18[2] = 1.0;
+        data18[3] = 1.0;
+        data18[4] = 1.0;
+        data18[5] = 1.0;
 
         write_dset(gid1, 1, dims1, "fp17", H5T_NATIVE_DOUBLE, data17);
         write_dset(gid1, 1, dims1, "fp18", H5T_NATIVE_DOUBLE, data18);
@@ -519,11 +519,11 @@ test_basic(const char *fname1, const char *fname2, const char *fname3)
         float  data19[6];
         double data20[6];
 
-        data19[0] = data19[1] = data19[2] = (float)HDlog(0.0F);
-        data19[3] = data19[4] = data19[5] = (float)-HDlog(0.0F);
+        data19[0] = data19[1] = data19[2] = (float)HDlog(0.0);
+        data19[3] = data19[4] = data19[5] = (float)-HDlog(0.0);
 
-        data20[0] = data20[1] = data20[2] = HDlog(0.0F);
-        data20[3] = data20[4] = data20[5] = -HDlog(0.0F);
+        data20[0] = data20[1] = data20[2] = HDlog(0.0);
+        data20[3] = data20[4] = data20[5] = -HDlog(0.0);
 
         write_dset(gid1, 1, dims1, "fp19", H5T_NATIVE_FLOAT, data19);
         write_dset(gid1, 1, dims1, "fp19_COPY", H5T_NATIVE_FLOAT, data19);
@@ -547,13 +547,13 @@ test_basic(const char *fname1, const char *fname2, const char *fname3)
         size_t  type_size;
         hid_t   tid;
 
-        buf1[0].d = HDsqrt(-1.0F);
-        buf1[0].f = (float)HDsqrt(-1.0F);
-        buf2[0].d = HDsqrt(-1.0F);
-        buf2[0].f = (float)HDsqrt(-1.0F);
+        buf1[0].d = HDsqrt(-1.0);
+        buf1[0].f = (float)HDsqrt(-1.0);
+        buf2[0].d = HDsqrt(-1.0);
+        buf2[0].f = (float)HDsqrt(-1.0);
 
-        buf1[1].d = HDsqrt(-1.0F);
-        buf1[1].f = (float)HDsqrt(-1.0F);
+        buf1[1].d = HDsqrt(-1.0);
+        buf1[1].f = (float)HDsqrt(-1.0);
         buf2[1].d = 0.0F;
         buf2[1].f = 0.0F;
 
@@ -5009,8 +5009,6 @@ error:
         H5Tclose(tid2);
     }
     H5E_END_TRY;
-
-    return;
 }
 
 static hid_t
@@ -8017,7 +8015,6 @@ test_double_epsilon(const char *fname1, const char *fname2)
 {
     hid_t   fid1 = H5I_INVALID_HID, fid2 = H5I_INVALID_HID;
     hsize_t dims1[2] = {4, 7};
-    hsize_t dims2[2] = {4, 7};
     double  wdata[4][7];
     int     i, j;
 
@@ -8059,8 +8056,6 @@ error:
         H5Fclose(fid2);
     }
     H5E_END_TRY;
-
-    return;
 }
 
 /*-------------------------------------------------------------------------
diff --git a/tools/test/h5diff/testfiles/h5diff_10.txt b/tools/test/h5diff/testfiles/h5diff_10.txt
index b5ff01a..3631db7 100644
--- a/tools/test/h5diff/testfiles/h5diff_10.txt
+++ b/tools/test/h5diff/testfiles/h5diff_10.txt
@@ -143,6 +143,18 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[ obj2]]
       (The option --follow-symlinks overrides the default behavior when
        symbolic links are compared.).
 
+ Subsetting options:
+  Subsetting is available by using the fcompact form of subsetting, as follows:
+    obj1 /foo/mydataset[START;STRIDE;COUNT;BLOCK]
+  It is not required to use all parameters, but until the last parameter value used,
+  all of the semicolons (;) are required, even when a parameter value is not specified. Example:
+    obj1 /foo/mydataset[START;;COUNT;BLOCK]
+    obj1 /foo/mydataset[START]
+  The STRIDE, COUNT, and BLOCK parameters are optional and will default to 1 in
+  each dimension. START is optional and will default to 0 in each dimension.
+  Each of START, STRIDE, COUNT, and BLOCK must be a comma-separated list of integers with
+  one integer for each dimension of the dataset.
+
  Exit code:
   0 if no differences, 1 if differences found, 2 if error
 
diff --git a/tools/test/h5diff/testfiles/h5diff_600.txt b/tools/test/h5diff/testfiles/h5diff_600.txt
index f52d8cc..8a4ce6d 100644
--- a/tools/test/h5diff/testfiles/h5diff_600.txt
+++ b/tools/test/h5diff/testfiles/h5diff_600.txt
@@ -143,6 +143,18 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[ obj2]]
       (The option --follow-symlinks overrides the default behavior when
        symbolic links are compared.).
 
+ Subsetting options:
+  Subsetting is available by using the fcompact form of subsetting, as follows:
+    obj1 /foo/mydataset[START;STRIDE;COUNT;BLOCK]
+  It is not required to use all parameters, but until the last parameter value used,
+  all of the semicolons (;) are required, even when a parameter value is not specified. Example:
+    obj1 /foo/mydataset[START;;COUNT;BLOCK]
+    obj1 /foo/mydataset[START]
+  The STRIDE, COUNT, and BLOCK parameters are optional and will default to 1 in
+  each dimension. START is optional and will default to 0 in each dimension.
+  Each of START, STRIDE, COUNT, and BLOCK must be a comma-separated list of integers with
+  one integer for each dimension of the dataset.
+
  Exit code:
   0 if no differences, 1 if differences found, 2 if error
 
diff --git a/tools/test/h5diff/testfiles/h5diff_603.txt b/tools/test/h5diff/testfiles/h5diff_603.txt
index 84111b3..d4c7336 100644
--- a/tools/test/h5diff/testfiles/h5diff_603.txt
+++ b/tools/test/h5diff/testfiles/h5diff_603.txt
@@ -144,6 +144,18 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[ obj2]]
       (The option --follow-symlinks overrides the default behavior when
        symbolic links are compared.).
 
+ Subsetting options:
+  Subsetting is available by using the fcompact form of subsetting, as follows:
+    obj1 /foo/mydataset[START;STRIDE;COUNT;BLOCK]
+  It is not required to use all parameters, but until the last parameter value used,
+  all of the semicolons (;) are required, even when a parameter value is not specified. Example:
+    obj1 /foo/mydataset[START;;COUNT;BLOCK]
+    obj1 /foo/mydataset[START]
+  The STRIDE, COUNT, and BLOCK parameters are optional and will default to 1 in
+  each dimension. START is optional and will default to 0 in each dimension.
+  Each of START, STRIDE, COUNT, and BLOCK must be a comma-separated list of integers with
+  one integer for each dimension of the dataset.
+
  Exit code:
   0 if no differences, 1 if differences found, 2 if error
 
diff --git a/tools/test/h5diff/testfiles/h5diff_606.txt b/tools/test/h5diff/testfiles/h5diff_606.txt
index d915d36..3123587 100644
--- a/tools/test/h5diff/testfiles/h5diff_606.txt
+++ b/tools/test/h5diff/testfiles/h5diff_606.txt
@@ -144,6 +144,18 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[ obj2]]
       (The option --follow-symlinks overrides the default behavior when
        symbolic links are compared.).
 
+ Subsetting options:
+  Subsetting is available by using the fcompact form of subsetting, as follows:
+    obj1 /foo/mydataset[START;STRIDE;COUNT;BLOCK]
+  It is not required to use all parameters, but until the last parameter value used,
+  all of the semicolons (;) are required, even when a parameter value is not specified. Example:
+    obj1 /foo/mydataset[START;;COUNT;BLOCK]
+    obj1 /foo/mydataset[START]
+  The STRIDE, COUNT, and BLOCK parameters are optional and will default to 1 in
+  each dimension. START is optional and will default to 0 in each dimension.
+  Each of START, STRIDE, COUNT, and BLOCK must be a comma-separated list of integers with
+  one integer for each dimension of the dataset.
+
  Exit code:
   0 if no differences, 1 if differences found, 2 if error
 
diff --git a/tools/test/h5diff/testfiles/h5diff_612.txt b/tools/test/h5diff/testfiles/h5diff_612.txt
index 1ef8cdf..ce2d887 100644
--- a/tools/test/h5diff/testfiles/h5diff_612.txt
+++ b/tools/test/h5diff/testfiles/h5diff_612.txt
@@ -144,6 +144,18 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[ obj2]]
       (The option --follow-symlinks overrides the default behavior when
        symbolic links are compared.).
 
+ Subsetting options:
+  Subsetting is available by using the fcompact form of subsetting, as follows:
+    obj1 /foo/mydataset[START;STRIDE;COUNT;BLOCK]
+  It is not required to use all parameters, but until the last parameter value used,
+  all of the semicolons (;) are required, even when a parameter value is not specified. Example:
+    obj1 /foo/mydataset[START;;COUNT;BLOCK]
+    obj1 /foo/mydataset[START]
+  The STRIDE, COUNT, and BLOCK parameters are optional and will default to 1 in
+  each dimension. START is optional and will default to 0 in each dimension.
+  Each of START, STRIDE, COUNT, and BLOCK must be a comma-separated list of integers with
+  one integer for each dimension of the dataset.
+
  Exit code:
   0 if no differences, 1 if differences found, 2 if error
 
diff --git a/tools/test/h5diff/testfiles/h5diff_615.txt b/tools/test/h5diff/testfiles/h5diff_615.txt
index 881362e..61fd036 100644
--- a/tools/test/h5diff/testfiles/h5diff_615.txt
+++ b/tools/test/h5diff/testfiles/h5diff_615.txt
@@ -144,6 +144,18 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[ obj2]]
       (The option --follow-symlinks overrides the default behavior when
        symbolic links are compared.).
 
+ Subsetting options:
+  Subsetting is available by using the fcompact form of subsetting, as follows:
+    obj1 /foo/mydataset[START;STRIDE;COUNT;BLOCK]
+  It is not required to use all parameters, but until the last parameter value used,
+  all of the semicolons (;) are required, even when a parameter value is not specified. Example:
+    obj1 /foo/mydataset[START;;COUNT;BLOCK]
+    obj1 /foo/mydataset[START]
+  The STRIDE, COUNT, and BLOCK parameters are optional and will default to 1 in
+  each dimension. START is optional and will default to 0 in each dimension.
+  Each of START, STRIDE, COUNT, and BLOCK must be a comma-separated list of integers with
+  one integer for each dimension of the dataset.
+
  Exit code:
   0 if no differences, 1 if differences found, 2 if error
 
diff --git a/tools/test/h5diff/testfiles/h5diff_621.txt b/tools/test/h5diff/testfiles/h5diff_621.txt
index ba39a99..dc8655d 100644
--- a/tools/test/h5diff/testfiles/h5diff_621.txt
+++ b/tools/test/h5diff/testfiles/h5diff_621.txt
@@ -144,6 +144,18 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[ obj2]]
       (The option --follow-symlinks overrides the default behavior when
        symbolic links are compared.).
 
+ Subsetting options:
+  Subsetting is available by using the fcompact form of subsetting, as follows:
+    obj1 /foo/mydataset[START;STRIDE;COUNT;BLOCK]
+  It is not required to use all parameters, but until the last parameter value used,
+  all of the semicolons (;) are required, even when a parameter value is not specified. Example:
+    obj1 /foo/mydataset[START;;COUNT;BLOCK]
+    obj1 /foo/mydataset[START]
+  The STRIDE, COUNT, and BLOCK parameters are optional and will default to 1 in
+  each dimension. START is optional and will default to 0 in each dimension.
+  Each of START, STRIDE, COUNT, and BLOCK must be a comma-separated list of integers with
+  one integer for each dimension of the dataset.
+
  Exit code:
   0 if no differences, 1 if differences found, 2 if error
 
diff --git a/tools/test/h5diff/testfiles/h5diff_622.txt b/tools/test/h5diff/testfiles/h5diff_622.txt
index 70421fc..f20ffbe 100644
--- a/tools/test/h5diff/testfiles/h5diff_622.txt
+++ b/tools/test/h5diff/testfiles/h5diff_622.txt
@@ -144,6 +144,18 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[ obj2]]
       (The option --follow-symlinks overrides the default behavior when
        symbolic links are compared.).
 
+ Subsetting options:
+  Subsetting is available by using the fcompact form of subsetting, as follows:
+    obj1 /foo/mydataset[START;STRIDE;COUNT;BLOCK]
+  It is not required to use all parameters, but until the last parameter value used,
+  all of the semicolons (;) are required, even when a parameter value is not specified. Example:
+    obj1 /foo/mydataset[START;;COUNT;BLOCK]
+    obj1 /foo/mydataset[START]
+  The STRIDE, COUNT, and BLOCK parameters are optional and will default to 1 in
+  each dimension. START is optional and will default to 0 in each dimension.
+  Each of START, STRIDE, COUNT, and BLOCK must be a comma-separated list of integers with
+  one integer for each dimension of the dataset.
+
  Exit code:
   0 if no differences, 1 if differences found, 2 if error
 
diff --git a/tools/test/h5diff/testfiles/h5diff_623.txt b/tools/test/h5diff/testfiles/h5diff_623.txt
index 0d74268..f73d202 100644
--- a/tools/test/h5diff/testfiles/h5diff_623.txt
+++ b/tools/test/h5diff/testfiles/h5diff_623.txt
@@ -144,6 +144,18 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[ obj2]]
       (The option --follow-symlinks overrides the default behavior when
        symbolic links are compared.).
 
+ Subsetting options:
+  Subsetting is available by using the fcompact form of subsetting, as follows:
+    obj1 /foo/mydataset[START;STRIDE;COUNT;BLOCK]
+  It is not required to use all parameters, but until the last parameter value used,
+  all of the semicolons (;) are required, even when a parameter value is not specified. Example:
+    obj1 /foo/mydataset[START;;COUNT;BLOCK]
+    obj1 /foo/mydataset[START]
+  The STRIDE, COUNT, and BLOCK parameters are optional and will default to 1 in
+  each dimension. START is optional and will default to 0 in each dimension.
+  Each of START, STRIDE, COUNT, and BLOCK must be a comma-separated list of integers with
+  one integer for each dimension of the dataset.
+
  Exit code:
   0 if no differences, 1 if differences found, 2 if error
 
diff --git a/tools/test/h5diff/testfiles/h5diff_624.txt b/tools/test/h5diff/testfiles/h5diff_624.txt
index cb8b8b4..903b738 100644
--- a/tools/test/h5diff/testfiles/h5diff_624.txt
+++ b/tools/test/h5diff/testfiles/h5diff_624.txt
@@ -144,6 +144,18 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[ obj2]]
       (The option --follow-symlinks overrides the default behavior when
        symbolic links are compared.).
 
+ Subsetting options:
+  Subsetting is available by using the fcompact form of subsetting, as follows:
+    obj1 /foo/mydataset[START;STRIDE;COUNT;BLOCK]
+  It is not required to use all parameters, but until the last parameter value used,
+  all of the semicolons (;) are required, even when a parameter value is not specified. Example:
+    obj1 /foo/mydataset[START;;COUNT;BLOCK]
+    obj1 /foo/mydataset[START]
+  The STRIDE, COUNT, and BLOCK parameters are optional and will default to 1 in
+  each dimension. START is optional and will default to 0 in each dimension.
+  Each of START, STRIDE, COUNT, and BLOCK must be a comma-separated list of integers with
+  one integer for each dimension of the dataset.
+
  Exit code:
   0 if no differences, 1 if differences found, 2 if error
 
diff --git a/tools/test/h5diff/testfiles/h5diff_830.txt b/tools/test/h5diff/testfiles/h5diff_830.txt
new file mode 100644
index 0000000..8f00d8b
--- /dev/null
+++ b/tools/test/h5diff/testfiles/h5diff_830.txt
@@ -0,0 +1,30 @@
+dataset: </g1/array3D> and </g1/array3D>
+size:           [4x3x2]           [4x3x2]
+position        array3D         array3D         difference          
+------------------------------------------------------------
+[ 0 0 0 ]          1               0               1              
+[ 0 0 0 ]          2               0               2              
+[ 0 0 0 ]          3               0               3              
+[ 0 0 1 ]          4               0               4              
+[ 0 0 1 ]          5               0               5              
+[ 0 0 1 ]          6               0               6              
+[ 0 2 0 ]          13              0               13             
+[ 0 2 0 ]          14              0               14             
+[ 0 2 0 ]          15              0               15             
+[ 0 2 1 ]          16              0               16             
+[ 0 2 1 ]          17              0               17             
+[ 0 2 1 ]          18              0               18             
+[ 2 0 0 ]          37              0               37             
+[ 2 0 0 ]          38              0               38             
+[ 2 0 0 ]          39              0               39             
+[ 2 0 1 ]          40              0               40             
+[ 2 0 1 ]          41              0               41             
+[ 2 0 1 ]          42              0               42             
+[ 2 2 0 ]          49              0               49             
+[ 2 2 0 ]          50              0               50             
+[ 2 2 0 ]          51              0               51             
+[ 2 2 1 ]          52              0               52             
+[ 2 2 1 ]          53              0               53             
+[ 2 2 1 ]          54              0               54             
+24 differences found
+EXIT CODE: 1
diff --git a/tools/test/h5diff/testh5diff.sh.in b/tools/test/h5diff/testh5diff.sh.in
index c8f8ed2..bd27dd0 100644
--- a/tools/test/h5diff/testh5diff.sh.in
+++ b/tools/test/h5diff/testh5diff.sh.in
@@ -354,6 +354,7 @@ $SRC_H5DIFF_TESTFILES/h5diff_710.txt
 $SRC_H5DIFF_TESTFILES/h5diff_80.txt
 $SRC_H5DIFF_TESTFILES/h5diff_800.txt
 $SRC_H5DIFF_TESTFILES/h5diff_801.txt
+$SRC_H5DIFF_TESTFILES/h5diff_830.txt
 $SRC_H5DIFF_TESTFILES/h5diff_90.txt
 $SRC_H5DIFF_TESTFILES/h5diff_8625.txt
 $SRC_H5DIFF_TESTFILES/h5diff_8639.txt
@@ -1204,7 +1205,7 @@ TOOLTEST h5diff_801.txt -v h5diff_dset1.h5 h5diff_dset3.h5 /g1/array /g1/array
 # ##############################################################################
 # # dataset subsets
 # ##############################################################################
-#TRILABS_227 TOOLTEST h5diff_830.txt --enable-error-stack -v h5diff_dset1.h5 h5diff_dset2.h5 /g1/array3D[0,0,0;2,2,1;2,2,2;] /g1/array3D[0,0,0;2,2,1;2,2,2;]
+#TOOLTEST h5diff_830.txt --enable-error-stack -v h5diff_dset1.h5 h5diff_dset2.h5 "/g1/array3D[0,0,0;2,2,1;2,2,2;]" "/g1/array3D[0,0,0;2,2,1;2,2,2;]"
 
 # ##############################################################################
 # VDS tests