Merge pull request #1590 in HDFFV/hdf5 from ~LRKNOX/hdf5_lrk:1.10/master to 1.10/masterhdf5-1_10_5

* commit '6819c11508b0610f222fe3bfe8a19f637bf4319c': (154 commits) CMake needs a tar.gz examples file for windows, too. Correct file permissions on README.txt. Address merge anomalies and incorrect file permissions. Update release date in README.txt and RELEASE.txt. Revisions to Platforms tested. Updated LT_VERS_AGE in config/lt_vers.am due to reinstatement of previously removed symbols, then ran autogen.sh to propagate so number changes and H5E_LOGFAIL_g addition to files checked in on release branch. Updated H5err.txt to replace a global variable that was removed during the metadata cache logging changes (to maintain binary compatibility). HDFFV-10552,10686 restore H5O_*1 functions Minor fix in h5str_sprintf for NULL region references Add new files to MANIFEST. Update so version numbers. fix 2 typos. Update RELEASE.txt for TRILABS-34 and remove unused sections. Add script for building HDF5 with CMake on HPC machines that use sbatch. Add README file for inclusion in CMake-hdf5-<version>.tar.gz file. Add updated README_HPC file with cross compile instructions. set version to 1.10.5-pre1. Change default build mode to production. Merge pull request #1560 in HDFFV/hdf5 from hdf5-1-10-documentation-only to hdf5_1_10_5 Update HISTORY-1_10.txt and RELEASE.txt files. Modify RELEASE.txt in response to PR comments Check in files generated by autogen.sh for hdf5_1_10_5 release branch. Check in files generated by autogen.sh for hdf5_1_10_5 release branch. 2019/02/16. Code improvement ...
author: Larry Knox <lrknox@hdfgroup.org> 2019-02-28 21:24:02 (GMT)
committer: Larry Knox <lrknox@hdfgroup.org> 2019-02-28 21:24:02 (GMT)
commit: 646fc294078f560fc9bef784cb1c4e27cdc51f5b (patch)
tree: 21502062cfc4ab6410f6d81de11e28c1523e85bd /test
parent: 5eef94f83f4875b64ffe7f9cea05d965bddbd802 (diff)
parent: 6819c11508b0610f222fe3bfe8a19f637bf4319c (diff)
download: hdf5-hdf5-1_10_5.zip
hdf5-hdf5-1_10_5.tar.gz
hdf5-hdf5-1_10_5.tar.bz2
31 files changed, 5384 insertions, 2006 deletions
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index c8119fe..fa303ed 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -62,6 +62,7 @@ endif ()
 #################################################################################
 # If filter plugin tests can be tested
 #################################################################################
+if (BUILD_SHARED_LIBS)
   # make plugins dir
   file (MAKE_DIRECTORY "${CMAKE_BINARY_DIR}/filter_plugin_dir1")
   file (MAKE_DIRECTORY "${CMAKE_BINARY_DIR}/filter_plugin_dir2")
@@ -127,6 +128,7 @@ endif ()
           "${CMAKE_BINARY_DIR}/filter_plugin_dir2/$<TARGET_FILE_NAME:${HDF5_TEST_PLUGIN_TARGET}>"
     )
   endforeach ()
+endif ()
 
 #################################################################################
 #  Test program sources
@@ -197,6 +199,7 @@ set (H5_TESTS
     page_buffer
     dtypes
     dsets
+    chunk_info
     cmpd_dset
     filter_fail
     extend
@@ -339,6 +342,7 @@ set (H5_CHECK_TESTS
     atomic_reader
     links_env
     filenotclosed
+    del_many_dense_attrs
     flushrefresh
 )
 
diff --git a/test/CMakeTests.cmake b/test/CMakeTests.cmake
index 8838c34..a8dd647 100644
--- a/test/CMakeTests.cmake
+++ b/test/CMakeTests.cmake
@@ -171,6 +171,7 @@ set (HDF5_REFERENCE_TEST_FILES
     le_data.h5
     le_extlink1.h5
     le_extlink2.h5
+    corrupted_name_len.h5
     mergemsg.h5
     multi_file_v16-r.h5
     multi_file_v16-s.h5
@@ -230,47 +231,31 @@ add_test (NAME H5TEST-clear-testhdf5-objects
 )
 set_tests_properties (H5TEST-clear-testhdf5-objects PROPERTIES FIXTURES_SETUP clear_testhdf5)
 
-if (HDF5_ENABLE_USING_MEMCHECKER)
-  add_test (NAME H5TEST-testhdf5-base COMMAND $<TARGET_FILE:testhdf5> -x heap -x file -x select)
-  set_tests_properties (H5TEST-testhdf5-base PROPERTIES
-      FIXTURES_REQUIRED clear_testhdf5
-      ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST"
-      WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
-  )
-  add_test (NAME H5TEST-testhdf5-heap COMMAND $<TARGET_FILE:testhdf5> -o heap)
-  set_tests_properties (H5TEST-testhdf5-heap PROPERTIES
-      FIXTURES_REQUIRED clear_testhdf5
-      ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST"
-      WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
-  )
-  add_test (NAME H5TEST-testhdf5-file COMMAND $<TARGET_FILE:testhdf5> -o file)
-  set_tests_properties (H5TEST-testhdf5-file PROPERTIES
-      FIXTURES_REQUIRED clear_testhdf5
-      ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST"
-      WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
-  )
-  add_test (NAME H5TEST-testhdf5-select COMMAND $<TARGET_FILE:testhdf5> -o select)
-  set_tests_properties (H5TEST-testhdf5-select PROPERTIES
-      FIXTURES_REQUIRED clear_testhdf5
-      ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST"
-      WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
-  )
-else ()
-  add_test (NAME H5TEST-testhdf5 COMMAND "${CMAKE_COMMAND}"
-      -D "TEST_PROGRAM=$<TARGET_FILE:testhdf5>"
-      -D "TEST_ARGS:STRING="
-      -D "TEST_EXPECT=0"
-      -D "TEST_SKIP_COMPARE=TRUE"
-      -D "TEST_OUTPUT=testhdf5.txt"
-      #-D "TEST_REFERENCE=testhdf5.out"
-      -D "TEST_FOLDER=${HDF5_TEST_BINARY_DIR}/H5TEST"
-      -P "${HDF_RESOURCES_EXT_DIR}/runTest.cmake"
-  )
-  set_tests_properties (H5TEST-testhdf5 PROPERTIES
-      FIXTURES_REQUIRED clear_testhdf5
-      ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST"
-      WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
-  )
+add_test (NAME H5TEST-testhdf5-base COMMAND $<TARGET_FILE:testhdf5> -x heap -x file -x select)
+set_tests_properties (H5TEST-testhdf5-base PROPERTIES
+    FIXTURES_REQUIRED clear_testhdf5
+    ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST"
+    WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
+)
+add_test (NAME H5TEST-testhdf5-heap COMMAND $<TARGET_FILE:testhdf5> -o heap)
+set_tests_properties (H5TEST-testhdf5-heap PROPERTIES
+    FIXTURES_REQUIRED clear_testhdf5
+    ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST"
+    WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
+)
+add_test (NAME H5TEST-testhdf5-file COMMAND $<TARGET_FILE:testhdf5> -o file)
+set_tests_properties (H5TEST-testhdf5-file PROPERTIES
+    FIXTURES_REQUIRED clear_testhdf5
+    ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST"
+    WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
+)
+add_test (NAME H5TEST-testhdf5-select COMMAND $<TARGET_FILE:testhdf5> -o select)
+set_tests_properties (H5TEST-testhdf5-select PROPERTIES
+    FIXTURES_REQUIRED clear_testhdf5
+    ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST"
+    WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
+)
+if (NOT HDF5_ENABLE_USING_MEMCHECKER)
   if (BUILD_SHARED_LIBS)
     add_test (NAME H5TEST-shared-clear-testhdf5-objects
         COMMAND    ${CMAKE_COMMAND}
@@ -297,19 +282,28 @@ else ()
             ${HDF5_TEST_BINARY_DIR}/H5TEST-shared
     )
     set_tests_properties (H5TEST-shared-clear-testhdf5-objects PROPERTIES FIXTURES_SETUP shared_clear_testhdf5)
-    add_test (NAME H5TEST-shared-testhdf5 COMMAND "${CMAKE_COMMAND}"
-        -D "TEST_PROGRAM=$<TARGET_FILE:testhdf5-shared>"
-        -D "TEST_ARGS:STRING="
-        -D "TEST_EXPECT=0"
-        -D "TEST_SKIP_COMPARE=TRUE"
-        -D "TEST_OUTPUT=testhdf5.txt"
-        #-D "TEST_REFERENCE=testhdf5.out"
-        -D "TEST_FOLDER=${HDF5_TEST_BINARY_DIR}/H5TEST-shared"
-        -P "${HDF_RESOURCES_EXT_DIR}/runTest.cmake"
+    add_test (NAME H5TEST-shared-testhdf5-base COMMAND $<TARGET_FILE:testhdf5-shared> -x heap -x file -x select)
+    set_tests_properties (H5TEST-shared-testhdf5-base PROPERTIES
+        FIXTURES_REQUIRED shared_clear_testhdf5
+        ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST-shared"
+        WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST-shared
     )
-    set_tests_properties (H5TEST-shared-testhdf5 PROPERTIES
+    add_test (NAME H5TEST-shared-testhdf5-heap COMMAND $<TARGET_FILE:testhdf5-shared> -o heap)
+    set_tests_properties (H5TEST-shared-testhdf5-heap PROPERTIES
         FIXTURES_REQUIRED shared_clear_testhdf5
-        ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST-shared"
+        ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST-shared"
+        WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST-shared
+    )
+    add_test (NAME H5TEST-shared-testhdf5-file COMMAND $<TARGET_FILE:testhdf5-shared> -o file)
+    set_tests_properties (H5TEST-shared-testhdf5-file PROPERTIES
+        FIXTURES_REQUIRED shared_clear_testhdf5
+        ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST-shared"
+        WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST-shared
+    )
+    add_test (NAME H5TEST-shared-testhdf5-select COMMAND $<TARGET_FILE:testhdf5-shared> -o select)
+    set_tests_properties (H5TEST-shared-testhdf5-select PROPERTIES
+        FIXTURES_REQUIRED shared_clear_testhdf5
+        ENVIRONMENT "HDF5_ALARM_SECONDS=3600;srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST-shared"
         WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST-shared
     )
   endif ()
@@ -359,6 +353,9 @@ set (test_CLEANFILES
     lheap.h5
     fheap.h5
     ohdr.h5
+    ohdr_min_a.h5
+    ohdr_min_b.h5
+    min_dset_ohdr_testfile.h5
     stab.h5
     extern_*.h5
     extern_*.raw
@@ -517,6 +514,7 @@ set (test_CLEANFILES
     flushrefresh_VERIFICATION_CHECKPOINT2
     flushrefresh_VERIFICATION_DONE
     filenotclosed.h5
+    del_many_dense_attrs.h5
     atomic_data
     accum_swmr_big.h5
     ohdr_swmr.h5
@@ -581,10 +579,10 @@ foreach (test ${H5_TESTS})
   endif ()
 endforeach ()
 
-set_tests_properties (H5TEST-fheap PROPERTIES TIMEOUT 1800)
-set_tests_properties (H5TEST-big PROPERTIES TIMEOUT 1800)
-set_tests_properties (H5TEST-btree2 PROPERTIES TIMEOUT 1800)
-set_tests_properties (H5TEST-objcopy PROPERTIES TIMEOUT 1800)
+set_tests_properties (H5TEST-fheap PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
+set_tests_properties (H5TEST-big PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
+set_tests_properties (H5TEST-btree2 PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
+set_tests_properties (H5TEST-objcopy PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
 
 if (BUILD_SHARED_LIBS)
   # Remove any output file left over from previous test run
@@ -623,10 +621,10 @@ if (BUILD_SHARED_LIBS)
     endif ()
   endforeach ()
 
-  set_tests_properties (H5TEST-shared-fheap PROPERTIES TIMEOUT 1800)
-  set_tests_properties (H5TEST-shared-big PROPERTIES TIMEOUT 1800)
-  set_tests_properties (H5TEST-shared-btree2 PROPERTIES TIMEOUT 1800)
-  set_tests_properties (H5TEST-shared-objcopy PROPERTIES TIMEOUT 1800)
+  set_tests_properties (H5TEST-shared-fheap PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
+  set_tests_properties (H5TEST-shared-big PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
+  set_tests_properties (H5TEST-shared-btree2 PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
+  set_tests_properties (H5TEST-shared-objcopy PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
 endif ()
 
 #-- Adding test for cache
@@ -658,9 +656,10 @@ if (NOT CYGWIN)
       ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST;HDF5TestExpress=${HDF_TEST_EXPRESS}"
       WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
   )
-  set_tests_properties (H5TEST-cache PROPERTIES TIMEOUT 1800)
+  set_tests_properties (H5TEST-cache PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
 endif ()
 
+if (TEST_CACHE_IMAGE)
 #-- Adding test for cache_image
 add_test (
     NAME H5TEST-clear-cache_image-objects
@@ -677,6 +676,7 @@ set_tests_properties (H5TEST-cache_image PROPERTIES
     ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST;HDF5TestExpress=${HDF_TEST_EXPRESS}"
     WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
 )
+endif ()
 
 if (BUILD_SHARED_LIBS)
   #-- Adding test for cache
@@ -708,7 +708,7 @@ if (BUILD_SHARED_LIBS)
         ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST-shared;HDF5TestExpress=${HDF_TEST_EXPRESS}"
         WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST-shared
     )
-    set_tests_properties (H5TEST-shared-cache PROPERTIES TIMEOUT 1800)
+    set_tests_properties (H5TEST-shared-cache PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
   endif ()
 endif ()
 
@@ -792,6 +792,7 @@ set_tests_properties (H5TEST-tcheck_version-release PROPERTIES
 #    atomic_reader
 #    links_env
 #    filenotclosed
+#    del_many_dense_attrs
 #    flushrefresh
 ##############################################################################
 # autotools script tests
@@ -799,7 +800,7 @@ set_tests_properties (H5TEST-tcheck_version-release PROPERTIES
 # NOT CONVERTED accum_swmr_reader is used by accum.c.
 # NOT CONVERTED atomic_writer and atomic_reader are standalone programs.
 # links_env is used by testlinks_env.sh
-# filenotclosed is used by test_filenotclosed.sh
+# filenotclosed and del_many_dense_attrs are used by testabort_fail.sh
 # NOT CONVERTED flushrefresh is used by testflushrefresh.sh.
 # NOT CONVERTED use_append_chunk, use_append_mchunks and use_disable_mdc_flushes are used by test_usecases.sh
 # NOT CONVERTED swmr_* files (besides swmr.c) are used by testswmr.sh.
@@ -826,6 +827,23 @@ set_tests_properties (H5TEST-filenotclosed PROPERTIES
     WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
 )
 
+#-- Adding test for del_many_dense_attrs
+add_test (
+    NAME H5TEST-clear-del_many_dense_attrs-objects
+    COMMAND    ${CMAKE_COMMAND}
+        -E remove
+        del_many_dense_attrs.h5
+    WORKING_DIRECTORY
+        ${HDF5_TEST_BINARY_DIR}/H5TEST
+)
+set_tests_properties (H5TEST-clear-del_many_dense_attrs-objects PROPERTIES FIXTURES_SETUP  del_many_dense_attrs_clear_objects)
+add_test (NAME H5TEST-del_many_dense_attrs COMMAND $<TARGET_FILE:del_many_dense_attrs>)
+set_tests_properties (H5TEST-del_many_dense_attrs PROPERTIES
+    FIXTURES_REQUIRED del_many_dense_attrs_clear_objects
+    ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/H5TEST"
+    WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/H5TEST
+)
+
 #-- Adding test for err_compat
 if (HDF5_ENABLE_DEPRECATED_SYMBOLS)
   add_test (NAME H5TEST-clear-err_compat-objects
@@ -842,6 +860,7 @@ if (HDF5_ENABLE_DEPRECATED_SYMBOLS)
       -D "TEST_ARGS:STRING="
       -D "TEST_EXPECT=0"
       -D "TEST_MASK_ERROR=true"
+      -D "ERROR_APPEND=1"
       -D "TEST_OUTPUT=err_compat.txt"
       -D "TEST_REFERENCE=err_compat_1"
       -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/H5TEST"
@@ -876,6 +895,7 @@ else ()
       -D "TEST_ARGS:STRING="
       -D "TEST_EXPECT=0"
       -D "TEST_MASK_ERROR=true"
+      -D "ERROR_APPEND=1"
       -D "TEST_OUTPUT=error_test.txt"
       -D "TEST_REFERENCE=error_test_1"
       -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/H5TEST"
@@ -942,6 +962,7 @@ if (BUILD_SHARED_LIBS)
         -D "TEST_ARGS:STRING="
         -D "TEST_EXPECT=0"
         -D "TEST_MASK_ERROR=true"
+        -D "ERROR_APPEND=1"
         -D "TEST_OUTPUT=err_compat.txt"
         -D "TEST_REFERENCE=err_compat_1"
         -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/H5TEST-shared"
@@ -976,6 +997,7 @@ if (BUILD_SHARED_LIBS)
         -D "TEST_ARGS:STRING="
         -D "TEST_EXPECT=0"
         -D "TEST_MASK_ERROR=true"
+        -D "ERROR_APPEND=1"
         -D "TEST_OUTPUT=error_test.txt"
         -D "TEST_REFERENCE=error_test_1"
         -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/H5TEST-shared"
@@ -1029,42 +1051,44 @@ endif ()
 ##############################################################################
 ###    F I L T E R  P L U G I N  T E S T S
 ##############################################################################
-if (WIN32)
-  set (CMAKE_SEP "\;")
-  set (BIN_REL_PATH "../../")
-else ()
-  set (CMAKE_SEP ":")
-  set (BIN_REL_PATH "../")
-endif ()
+if (BUILD_SHARED_LIBS)
+  if (WIN32)
+    set (CMAKE_SEP "\;")
+    set (BIN_REL_PATH "../../")
+  else ()
+    set (CMAKE_SEP ":")
+    set (BIN_REL_PATH "../")
+  endif ()
 
-add_test (NAME H5PLUGIN-filter_plugin COMMAND $<TARGET_FILE:filter_plugin>)
-set_tests_properties (H5PLUGIN-filter_plugin PROPERTIES
-    ENVIRONMENT "HDF5_PLUGIN_PATH=${CMAKE_BINARY_DIR}/filter_plugin_dir1${CMAKE_SEP}${CMAKE_BINARY_DIR}/filter_plugin_dir2;srcdir=${HDF5_TEST_BINARY_DIR}"
-    WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}
-)
+  add_test (NAME H5PLUGIN-filter_plugin COMMAND $<TARGET_FILE:filter_plugin>)
+  set_tests_properties (H5PLUGIN-filter_plugin PROPERTIES
+      ENVIRONMENT "HDF5_PLUGIN_PATH=${CMAKE_BINARY_DIR}/filter_plugin_dir1${CMAKE_SEP}${CMAKE_BINARY_DIR}/filter_plugin_dir2;srcdir=${HDF5_TEST_BINARY_DIR}"
+      WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}
+  )
 
 ##############################################################################
 # HDFFV-9655 relative plugin test disabled
 #
-#add_test (NAME H5PLUGIN-pluginRelative COMMAND $<TARGET_FILE:plugin>)
-#set_tests_properties (H5PLUGIN-pluginRelative PROPERTIES
-#    ENVIRONMENT "HDF5_PLUGIN_PATH=@/${BIN_REL_PATH}testdir1${CMAKE_SEP}@/${BIN_REL_PATH}testdir2;srcdir=${HDF5_TEST_BINARY_DIR}"
-#    WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}
-#)
+#  add_test (NAME H5PLUGIN-pluginRelative COMMAND $<TARGET_FILE:plugin>)
+#  set_tests_properties (H5PLUGIN-pluginRelative PROPERTIES
+#      ENVIRONMENT "HDF5_PLUGIN_PATH=@/${BIN_REL_PATH}testdir1${CMAKE_SEP}@/${BIN_REL_PATH}testdir2;srcdir=${HDF5_TEST_BINARY_DIR}"
+#      WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}
+#  )
 ##############################################################################
+endif ()
 
 if (TEST_SHELL_SCRIPTS)
   include (ShellTests.cmake)
 endif()
 
 if (ENABLE_EXTENDED_TESTS)
-    ##############################################################################
-    ###    S W M R  T E S T S
-    ##############################################################################
-    #       testflushrefresh.sh: flushrefresh
-    #       test_usecases.sh: use_append_chunk, use_append_mchunks, use_disable_mdc_flushes
-    #       testswmr.sh: swmr*
-    #       testvdsswmr.sh: vds_swmr*
+##############################################################################
+###    S W M R  T E S T S
+##############################################################################
+#       testflushrefresh.sh: flushrefresh
+#       test_usecases.sh: use_append_chunk, use_append_mchunks, use_disable_mdc_flushes
+#       testswmr.sh: swmr*
+#       testvdsswmr.sh: vds_swmr*
 
 #  add_test (NAME H5Test-swmr_check_compat_vfd COMMAND $<TARGET_FILE:swmr_check_compat_vfd>)
 
diff --git a/test/CMakeVFDTests.cmake b/test/CMakeVFDTests.cmake
index be02110..569f215 100644
--- a/test/CMakeVFDTests.cmake
+++ b/test/CMakeVFDTests.cmake
@@ -92,6 +92,7 @@ endif ()
 
   set (H5_VFD_SKIP_TESTS
       cache
+      cache_image
       accum
       fheap
       big
@@ -111,32 +112,48 @@ endif ()
     if ("${vfdtest}" STREQUAL "flush1" OR "${vfdtest}" STREQUAL "flush2")
       if ("${vfdname}" STREQUAL "multi" OR "${vfdname}" STREQUAL "split")
         if (NOT BUILD_SHARED_LIBS AND NOT ${HDF_CFG_NAME} MATCHES "Debug")
+          add_test (
+              NAME VFD-${vfdname}-${vfdtest}-clear-objects
+              COMMAND    ${CMAKE_COMMAND}
+                  -E remove
+                      ${vfdname}/${vfdname}-${vfdtest}.out
+                      ${vfdname}/${vfdname}-${vfdtest}.out.err
+          )
           add_test (NAME VFD-${vfdname}-${vfdtest}
               COMMAND "${CMAKE_COMMAND}"
                   -D "TEST_PROGRAM=$<TARGET_FILE:${vfdtest}>"
                   -D "TEST_ARGS:STRING="
                   -D "TEST_VFD:STRING=${vfdname}"
                   -D "TEST_EXPECT=${resultcode}"
-                  -D "TEST_OUTPUT=${vfdname}-${vfdtest}"
+                  -D "TEST_OUTPUT=${vfdname}-${vfdtest}.out"
                   -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/${vfdname}"
                   -P "${HDF_RESOURCES_DIR}/vfdTest.cmake"
           )
           set_tests_properties (VFD-${vfdname}-${vfdtest} PROPERTIES
+              DEPENDS VFD-${vfdname}-${vfdtest}-clear-objects
               ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/${vfdname}"
               WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/${vfdname}
           )
           if (BUILD_SHARED_LIBS)
+            add_test (
+                NAME VFD-${vfdname}-${vfdtest}-shared-clear-objects
+                COMMAND    ${CMAKE_COMMAND}
+                    -E remove
+                        ${vfdname}-shared/${vfdname}-${vfdtest}-shared.out
+                        ${vfdname}-shared/${vfdname}-${vfdtest}-shared.out.err
+            )
             add_test (NAME VFD-${vfdname}-${test}-shared
                 COMMAND "${CMAKE_COMMAND}"
                     -D "TEST_PROGRAM=$<TARGET_FILE:${vfdtest}-shared>"
                     -D "TEST_ARGS:STRING="
                     -D "TEST_VFD:STRING=${vfdname}"
                     -D "TEST_EXPECT=${resultcode}"
-                    -D "TEST_OUTPUT=${vfdname}-${vfdtest}-shared"
+                    -D "TEST_OUTPUT=${vfdname}-${vfdtest}-shared.out"
                     -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/${vfdname}-shared"
                     -P "${HDF_RESOURCES_DIR}/vfdTest.cmake"
             )
             set_tests_properties (VFD-${vfdname}-${vfdtest}-shared PROPERTIES
+                DEPENDS VFD-${vfdname}-${vfdtest}-shared-clear-objects
                 ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/${vfdname}-shared"
                 WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/${vfdname}-shared
             )
@@ -152,64 +169,96 @@ endif ()
           endif ()
         endif ()
       else ()
+        add_test (
+            NAME VFD-${vfdname}-${vfdtest}-clear-objects
+            COMMAND    ${CMAKE_COMMAND}
+                -E remove
+                    ${vfdname}/${vfdname}-${vfdtest}.out
+                    ${vfdname}/${vfdname}-${vfdtest}.out.err
+        )
         add_test (NAME VFD-${vfdname}-${vfdtest}
             COMMAND "${CMAKE_COMMAND}"
                 -D "TEST_PROGRAM=$<TARGET_FILE:${vfdtest}>"
                 -D "TEST_ARGS:STRING="
                 -D "TEST_VFD:STRING=${vfdname}"
                 -D "TEST_EXPECT=${resultcode}"
-                -D "TEST_OUTPUT=${vfdname}-${vfdtest}"
+                -D "TEST_OUTPUT=${vfdname}-${vfdtest}.out"
                 -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/${vfdname}"
                 -P "${HDF_RESOURCES_DIR}/vfdTest.cmake"
         )
         set_tests_properties (VFD-${vfdname}-${vfdtest} PROPERTIES
+            DEPENDS VFD-${vfdname}-${vfdtest}-clear-objects
             ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/${vfdname}"
             WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/${vfdname}
         )
         if (BUILD_SHARED_LIBS)
+          add_test (
+              NAME VFD-${vfdname}-${vfdtest}-shared-clear-objects
+              COMMAND    ${CMAKE_COMMAND}
+                  -E remove
+                      ${vfdname}-shared/${vfdname}-${vfdtest}-shared.out
+                      ${vfdname}-shared/${vfdname}-${vfdtest}-shared.out.err
+          )
           add_test (NAME VFD-${vfdname}-${test}-shared
               COMMAND "${CMAKE_COMMAND}"
                 -D "TEST_PROGRAM=$<TARGET_FILE:${vfdtest}-shared>"
                 -D "TEST_ARGS:STRING="
                 -D "TEST_VFD:STRING=${vfdname}"
                 -D "TEST_EXPECT=${resultcode}"
-                -D "TEST_OUTPUT=${vfdname}-${vfdtest}-shared"
+                -D "TEST_OUTPUT=${vfdname}-${vfdtest}-shared.out"
                 -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/${vfdname}-shared"
                 -P "${HDF_RESOURCES_DIR}/vfdTest.cmake"
           )
           set_tests_properties (VFD-${vfdname}-${vfdtest}-shared PROPERTIES
+              DEPENDS VFD-${vfdname}-${vfdtest}-shared-clear-objects
               ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/${vfdname}-shared"
               WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/${vfdname}-shared
           )
         endif ()
       endif ()
     else ()
+      add_test (
+          NAME VFD-${vfdname}-${vfdtest}-clear-objects
+          COMMAND    ${CMAKE_COMMAND}
+              -E remove
+                  ${vfdname}/${vfdname}-${vfdtest}.out
+                  ${vfdname}/${vfdname}-${vfdtest}.out.err
+      )
       add_test (NAME VFD-${vfdname}-${vfdtest}
           COMMAND "${CMAKE_COMMAND}"
               -D "TEST_PROGRAM=$<TARGET_FILE:${vfdtest}>"
               -D "TEST_ARGS:STRING="
               -D "TEST_VFD:STRING=${vfdname}"
               -D "TEST_EXPECT=${resultcode}"
-              -D "TEST_OUTPUT=${vfdname}-${vfdtest}"
+              -D "TEST_OUTPUT=${vfdname}-${vfdtest}.out"
               -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/${vfdname}"
               -P "${HDF_RESOURCES_DIR}/vfdTest.cmake"
       )
       set_tests_properties (VFD-${vfdname}-${vfdtest} PROPERTIES
+          DEPENDS VFD-${vfdname}-${vfdtest}-clear-objects
           ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/${vfdname};HDF5TestExpress=${HDF_TEST_EXPRESS}"
           WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/${vfdname}
       )
       if (BUILD_SHARED_LIBS AND NOT "${vfdtest}" STREQUAL "cache")
+        add_test (
+            NAME VFD-${vfdname}-${vfdtest}-shared-clear-objects
+            COMMAND    ${CMAKE_COMMAND}
+                -E remove
+                    ${vfdname}-shared/${vfdname}-${vfdtest}-shared.out
+                    ${vfdname}-shared/${vfdname}-${vfdtest}-shared.out.err
+        )
         add_test (NAME VFD-${vfdname}-${vfdtest}-shared
             COMMAND "${CMAKE_COMMAND}"
                 -D "TEST_PROGRAM=$<TARGET_FILE:${vfdtest}-shared>"
                 -D "TEST_ARGS:STRING="
                 -D "TEST_VFD:STRING=${vfdname}"
                 -D "TEST_EXPECT=${resultcode}"
-                -D "TEST_OUTPUT=${vfdname}-${vfdtest}-shared"
+                -D "TEST_OUTPUT=${vfdname}-${vfdtest}-shared.out"
                 -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/${vfdname}-shared"
                 -P "${HDF_RESOURCES_DIR}/vfdTest.cmake"
         )
         set_tests_properties (VFD-${vfdname}-${vfdtest}-shared PROPERTIES
+            DEPENDS VFD-${vfdname}-${vfdtest}-shared-clear-objects
             ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/${vfdname}-shared;HDF5TestExpress=${HDF_TEST_EXPRESS}"
             WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/${vfdname}-shared
         )
@@ -218,32 +267,48 @@ endif ()
   endmacro ()
 
   macro (DO_VFD_TEST vfdtest vfdname resultcode)
+      add_test (
+          NAME VFD-${vfdname}-${vfdtest}-clear-objects
+          COMMAND    ${CMAKE_COMMAND}
+              -E remove
+                  ${vfdname}/${vfdname}-${vfdtest}.out
+                  ${vfdname}/${vfdname}-${vfdtest}.out.err
+      )
       add_test (NAME VFD-${vfdname}-${vfdtest}
           COMMAND "${CMAKE_COMMAND}"
               -D "TEST_PROGRAM=$<TARGET_FILE:${vfdtest}>"
               -D "TEST_ARGS:STRING="
               -D "TEST_VFD:STRING=${vfdname}"
               -D "TEST_EXPECT=${resultcode}"
-              -D "TEST_OUTPUT=${vfdname}-${vfdtest}"
+              -D "TEST_OUTPUT=${vfdname}-${vfdtest}.out"
               -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/${vfdname}"
               -P "${HDF_RESOURCES_DIR}/vfdTest.cmake"
       )
       set_tests_properties (VFD-${vfdname}-${vfdtest} PROPERTIES
+          DEPENDS VFD-${vfdname}-${vfdtest}-clear-objects
           ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/${vfdname}"
           WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/${vfdname}
       )
       if (BUILD_SHARED_LIBS)
+        add_test (
+            NAME VFD-${vfdname}-${vfdtest}-shared-clear-objects
+            COMMAND    ${CMAKE_COMMAND}
+                -E remove
+                    ${vfdname}-shared/${vfdname}-${vfdtest}-shared.out
+                    ${vfdname}-shared/${vfdname}-${vfdtest}-shared.out.err
+        )
         add_test (NAME VFD-${vfdname}-${vfdtest}-shared
             COMMAND "${CMAKE_COMMAND}"
                 -D "TEST_PROGRAM=$<TARGET_FILE:${vfdtest}-shared>"
                 -D "TEST_ARGS:STRING="
                 -D "TEST_VFD:STRING=${vfdname}"
                 -D "TEST_EXPECT=${resultcode}"
-                -D "TEST_OUTPUT=${vfdname}-${vfdtest}-shared"
+                -D "TEST_OUTPUT=${vfdname}-${vfdtest}-shared.out"
                 -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/${vfdname}-shared"
                 -P "${HDF_RESOURCES_DIR}/vfdTest.cmake"
         )
         set_tests_properties (VFD-${vfdname}-${vfdtest}-shared PROPERTIES
+            DEPENDS VFD-${vfdname}-${vfdtest}-shared-clear-objects
             ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/${vfdname}-shared"
             WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/${vfdname}-shared
         )
@@ -263,48 +328,64 @@ endif ()
     set_tests_properties (VFD-${vfdname}-flush2 PROPERTIES DEPENDS VFD-${vfdname}-flush1)
     set_tests_properties (VFD-${vfdname}-flush1 PROPERTIES TIMEOUT 10)
     set_tests_properties (VFD-${vfdname}-flush2 PROPERTIES TIMEOUT 10)
-    set_tests_properties (VFD-${vfdname}-istore PROPERTIES TIMEOUT 1800)
+    set_tests_properties (VFD-${vfdname}-istore PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
     if (NOT CYGWIN)
-      set_tests_properties (VFD-${vfdname}-cache PROPERTIES TIMEOUT 1800)
+      set_tests_properties (VFD-${vfdname}-cache PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
     endif ()
     if (BUILD_SHARED_LIBS)
       set_tests_properties (VFD-${vfdname}-flush2-shared PROPERTIES DEPENDS VFD-${vfdname}-flush1-shared)
       set_tests_properties (VFD-${vfdname}-flush1-shared PROPERTIES TIMEOUT 10)
       set_tests_properties (VFD-${vfdname}-flush2-shared PROPERTIES TIMEOUT 10)
-      set_tests_properties (VFD-${vfdname}-istore-shared PROPERTIES TIMEOUT 1800)
+      set_tests_properties (VFD-${vfdname}-istore-shared PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
       if (NOT CYGWIN AND NOT WIN32)
-        set_tests_properties (VFD-${vfdname}-cache-shared PROPERTIES TIMEOUT 1800)
+        set_tests_properties (VFD-${vfdname}-cache-shared PROPERTIES TIMEOUT ${CTEST_VERY_LONG_TIMEOUT})
       endif ()
     endif ()
     if (HDF5_TEST_FHEAP_VFD)
+      add_test (
+          NAME VFD-${vfdname}-fheap-clear-objects
+          COMMAND    ${CMAKE_COMMAND}
+              -E remove
+                  ${vfdname}/${vfdname}-fheap.out
+                  ${vfdname}/${vfdname}-fheap.out.err
+      )
       add_test (NAME VFD-${vfdname}-fheap
           COMMAND "${CMAKE_COMMAND}"
               -D "TEST_PROGRAM=$<TARGET_FILE:fheap>"
               -D "TEST_ARGS:STRING="
               -D "TEST_VFD:STRING=${vfdname}"
               -D "TEST_EXPECT=${resultcode}"
-              -D "TEST_OUTPUT=${vfdname}-fheap"
+              -D "TEST_OUTPUT=${vfdname}-fheap.out"
               -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/${vfdname}"
               -P "${HDF_RESOURCES_DIR}/vfdTest.cmake"
       )
       set_tests_properties (VFD-${vfdname}-fheap PROPERTIES
-          TIMEOUT 1800
+          DEPENDS VFD-${vfdname}-fheap-clear-objects
+          TIMEOUT ${CTEST_VERY_LONG_TIMEOUT}
           ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/${vfdname};HDF5TestExpress=${HDF_TEST_EXPRESS}"
           WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/${vfdname}
       )
       if (BUILD_SHARED_LIBS)
+        add_test (
+            NAME VFD-${vfdname}-fheap-shared-clear-objects
+            COMMAND    ${CMAKE_COMMAND}
+                -E remove
+                    ${vfdname}-shared/${vfdname}-fheap-shared.out
+                    ${vfdname}-shared/${vfdname}-fheap-shared.out.err
+        )
         add_test (NAME VFD-${vfdname}-fheap-shared
             COMMAND "${CMAKE_COMMAND}"
                 -D "TEST_PROGRAM=$<TARGET_FILE:fheap-shared>"
                 -D "TEST_ARGS:STRING="
                 -D "TEST_VFD:STRING=${vfdname}"
                 -D "TEST_EXPECT=${resultcode}"
-                -D "TEST_OUTPUT=${vfdname}-fheap-shared"
+                -D "TEST_OUTPUT=${vfdname}-fheap-shared.out"
                 -D "TEST_FOLDER=${PROJECT_BINARY_DIR}/${vfdname}-shared"
                 -P "${HDF_RESOURCES_DIR}/vfdTest.cmake"
         )
         set_tests_properties (VFD-${vfdname}-fheap-shared PROPERTIES
-            TIMEOUT 1800
+            DEPENDS VFD-${vfdname}-fheap-shared-clear-objects
+            TIMEOUT ${CTEST_VERY_LONG_TIMEOUT}
             ENVIRONMENT "srcdir=${HDF5_TEST_BINARY_DIR}/${vfdname}-shared;HDF5TestExpress=${HDF_TEST_EXPRESS}"
             WORKING_DIRECTORY ${HDF5_TEST_BINARY_DIR}/${vfdname}-shared
         )
diff --git a/test/Makefile.am b/test/Makefile.am
index d4db6d0..c4fb876 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -29,12 +29,13 @@ AM_CPPFLAGS+=-I$(top_srcdir)/src -I$(top_builddir)/src
 #       testflushrefresh.sh: flushrefresh
 #       testswmr.sh: swmr*
 #       testvdsswmr.sh: vds_swmr*
-#       test_filenotclosed.sh: filenotclosed.c
+#       testabort_fail.sh: filenotclosed.c and del_many_dense_attrs.c
 #       test_filter_plugin.sh: filter_plugin.c
 #       test_usecases.sh: use_append_chunk, use_append_mchunks, use_disable_mdc_flushes
-TEST_SCRIPT = testerror.sh testlibinfo.sh testcheck_version.sh testlinks_env.sh test_filenotclosed.sh\
-    testswmr.sh testvdsswmr.sh testflushrefresh.sh test_usecases.sh
-SCRIPT_DEPEND = error_test$(EXEEXT) err_compat$(EXEEXT) links_env$(EXEEXT) filenotclosed$(EXEEXT) \
+TEST_SCRIPT = testerror.sh testlibinfo.sh testcheck_version.sh testlinks_env.sh \
+    testswmr.sh testvdsswmr.sh testflushrefresh.sh test_usecases.sh testabort_fail.sh
+SCRIPT_DEPEND = error_test$(EXEEXT) err_compat$(EXEEXT) links_env$(EXEEXT) \
+    filenotclosed$(EXEEXT) del_many_dense_attrs$(EXEEXT) \
     flushrefresh$(EXEEXT) use_append_chunk$(EXEEXT) use_append_mchunks$(EXEEXT) use_disable_mdc_flushes$(EXEEXT) \
     swmr_generator$(EXEEXT) swmr_reader$(EXEEXT) swmr_writer$(EXEEXT) \
     swmr_remove_reader$(EXEEXT) swmr_remove_writer$(EXEEXT) swmr_addrem_writer$(EXEEXT) \
@@ -55,8 +56,8 @@ TEST_PROG= testhdf5 \
            cache cache_api cache_image cache_tagging lheap ohdr stab gheap \
            evict_on_close farray earray btree2 fheap \
            pool accum hyperslab istore bittests dt_arith page_buffer \
-           dtypes dsets cmpd_dset filter_fail extend direct_chunk external efc \
-           objcopy links unlink twriteorder big mtime fillval mount \
+           dtypes dsets chunk_info cmpd_dset filter_fail extend direct_chunk \
+           external efc objcopy links unlink twriteorder big mtime fillval mount \
            flush1 flush2 app_ref enum set_extent ttsafe enc_dec_plist \
            enc_dec_plist_cross_platform getname vfd ntypes dangle dtransform \
            reserved cross_read freespace mf vds file_image unregister \
@@ -68,7 +69,7 @@ TEST_PROG= testhdf5 \
 # accum_swmr_reader is used by accum.c.
 # atomic_writer and atomic_reader are standalone programs.
 # links_env is used by testlinks_env.sh
-# filenotclosed is used by test_filenotclosed.sh
+# filenotclosed and del_many_dense_attrs are used by testabort_fail.sh
 # flushrefresh is used by testflushrefresh.sh.
 # use_append_chunk, use_append_mchunks and use_disable_mdc_flushes are used by test_usecases.sh
 # swmr_* files (besides swmr.c) are used by testswmr.sh.
@@ -78,7 +79,8 @@ TEST_PROG= testhdf5 \
 # and this lets automake keep all its test programs in one place.
 check_PROGRAMS=$(TEST_PROG) error_test err_compat tcheck_version \
     testmeta accum_swmr_reader atomic_writer atomic_reader \
-    links_env filenotclosed flushrefresh use_append_chunk use_append_mchunks use_disable_mdc_flushes \
+    links_env filenotclosed del_many_dense_attrs flushrefresh \
+    use_append_chunk use_append_mchunks use_disable_mdc_flushes \
     swmr_generator swmr_start_write swmr_reader swmr_writer swmr_remove_reader \
     swmr_remove_writer swmr_addrem_writer swmr_sparse_reader swmr_sparse_writer \
     swmr_check_compat_vfd vds_swmr_gen vds_swmr_reader vds_swmr_writer
@@ -165,6 +167,7 @@ CHECK_CLEANFILES+=accum.h5 cmpd_dset.h5 compact_dataset.h5 dataset.h5 dset_offse
     extend.h5 istore.h5 extlinks*.h5 frspace.h5 links*.h5 \
     sys_file1 tfile[1-7].h5 th5s[1-4].h5 lheap.h5 fheap.h5 ohdr.h5 \
     stab.h5 extern_[1-5].h5 extern_[1-4][rw].raw gheap[0-4].h5 \
+    ohdr_min_a.h5 ohdr_min_b.h5 min_dset_ohdr_testfile.h5 \
     dt_arith[1-2] links.h5 links[0-6]*.h5 extlinks[0-15].h5 tmp \
     big.data big[0-9][0-9][0-9][0-9][0-9].h5  \
     stdio.h5 sec2.h5 dtypes[0-9].h5 dtypes1[0].h5 dt_arith[1-2].h5 tattr.h5 \
@@ -208,6 +211,6 @@ use_disable_mdc_flushes_SOURCES=use_disable_mdc_flushes.c
 
 # Temporary files.
 DISTCLEANFILES=testerror.sh testlibinfo.sh testcheck_version.sh testlinks_env.sh test_filter_plugin.sh \
-    testswmr.sh testvdsswmr.sh test_usecases.sh testflushrefresh.sh test_filenotclosed.sh
+    testswmr.sh testvdsswmr.sh test_usecases.sh testflushrefresh.sh testabort_fail.sh
 
 include $(top_srcdir)/config/conclude.am
diff --git a/test/Makefile.in b/test/Makefile.in
index 7e6bde1..198d4ab 100644
--- a/test/Makefile.in
+++ b/test/Makefile.in
@@ -110,16 +110,16 @@ check_PROGRAMS = $(am__EXEEXT_1) error_test$(EXEEXT) \
 	err_compat$(EXEEXT) tcheck_version$(EXEEXT) testmeta$(EXEEXT) \
 	accum_swmr_reader$(EXEEXT) atomic_writer$(EXEEXT) \
 	atomic_reader$(EXEEXT) links_env$(EXEEXT) \
-	filenotclosed$(EXEEXT) flushrefresh$(EXEEXT) \
-	use_append_chunk$(EXEEXT) use_append_mchunks$(EXEEXT) \
-	use_disable_mdc_flushes$(EXEEXT) swmr_generator$(EXEEXT) \
-	swmr_start_write$(EXEEXT) swmr_reader$(EXEEXT) \
-	swmr_writer$(EXEEXT) swmr_remove_reader$(EXEEXT) \
-	swmr_remove_writer$(EXEEXT) swmr_addrem_writer$(EXEEXT) \
-	swmr_sparse_reader$(EXEEXT) swmr_sparse_writer$(EXEEXT) \
-	swmr_check_compat_vfd$(EXEEXT) vds_swmr_gen$(EXEEXT) \
-	vds_swmr_reader$(EXEEXT) vds_swmr_writer$(EXEEXT) \
-	$(am__EXEEXT_2)
+	filenotclosed$(EXEEXT) del_many_dense_attrs$(EXEEXT) \
+	flushrefresh$(EXEEXT) use_append_chunk$(EXEEXT) \
+	use_append_mchunks$(EXEEXT) use_disable_mdc_flushes$(EXEEXT) \
+	swmr_generator$(EXEEXT) swmr_start_write$(EXEEXT) \
+	swmr_reader$(EXEEXT) swmr_writer$(EXEEXT) \
+	swmr_remove_reader$(EXEEXT) swmr_remove_writer$(EXEEXT) \
+	swmr_addrem_writer$(EXEEXT) swmr_sparse_reader$(EXEEXT) \
+	swmr_sparse_writer$(EXEEXT) swmr_check_compat_vfd$(EXEEXT) \
+	vds_swmr_gen$(EXEEXT) vds_swmr_reader$(EXEEXT) \
+	vds_swmr_writer$(EXEEXT) $(am__EXEEXT_2)
 @HAVE_SHARED_CONDITIONAL_TRUE@am__append_3 = filter_plugin
 @BUILD_ALL_CONDITIONAL_TRUE@noinst_PROGRAMS = $(am__EXEEXT_3)
 @DIRECT_VFD_CONDITIONAL_TRUE@am__append_4 = direct
@@ -150,9 +150,9 @@ DIST_COMMON = $(srcdir)/Makefile.am $(am__DIST_COMMON)
 mkinstalldirs = $(install_sh) -d
 CONFIG_HEADER = $(top_builddir)/src/H5config.h \
 	$(top_builddir)/fortran/src/H5config_f.inc
-CONFIG_CLEAN_FILES = H5srcdir_str.h testcheck_version.sh testerror.sh \
-	testflushrefresh.sh testlibinfo.sh testlinks_env.sh \
-	testswmr.sh testvdsswmr.sh test_filenotclosed.sh \
+CONFIG_CLEAN_FILES = H5srcdir_str.h testabort_fail.sh \
+	testcheck_version.sh testerror.sh testflushrefresh.sh \
+	testlibinfo.sh testlinks_env.sh testswmr.sh testvdsswmr.sh \
 	test_filter_plugin.sh test_usecases.sh
 CONFIG_CLEAN_VPATH_FILES =
 LTLIBRARIES = $(noinst_LTLIBRARIES)
@@ -220,11 +220,11 @@ am__EXEEXT_1 = testhdf5$(EXEEXT) cache$(EXEEXT) cache_api$(EXEEXT) \
 	btree2$(EXEEXT) fheap$(EXEEXT) pool$(EXEEXT) accum$(EXEEXT) \
 	hyperslab$(EXEEXT) istore$(EXEEXT) bittests$(EXEEXT) \
 	dt_arith$(EXEEXT) page_buffer$(EXEEXT) dtypes$(EXEEXT) \
-	dsets$(EXEEXT) cmpd_dset$(EXEEXT) filter_fail$(EXEEXT) \
-	extend$(EXEEXT) direct_chunk$(EXEEXT) external$(EXEEXT) \
-	efc$(EXEEXT) objcopy$(EXEEXT) links$(EXEEXT) unlink$(EXEEXT) \
-	twriteorder$(EXEEXT) big$(EXEEXT) mtime$(EXEEXT) \
-	fillval$(EXEEXT) mount$(EXEEXT) flush1$(EXEEXT) \
+	dsets$(EXEEXT) chunk_info$(EXEEXT) cmpd_dset$(EXEEXT) \
+	filter_fail$(EXEEXT) extend$(EXEEXT) direct_chunk$(EXEEXT) \
+	external$(EXEEXT) efc$(EXEEXT) objcopy$(EXEEXT) links$(EXEEXT) \
+	unlink$(EXEEXT) twriteorder$(EXEEXT) big$(EXEEXT) \
+	mtime$(EXEEXT) fillval$(EXEEXT) mount$(EXEEXT) flush1$(EXEEXT) \
 	flush2$(EXEEXT) app_ref$(EXEEXT) enum$(EXEEXT) \
 	set_extent$(EXEEXT) ttsafe$(EXEEXT) enc_dec_plist$(EXEEXT) \
 	enc_dec_plist_cross_platform$(EXEEXT) getname$(EXEEXT) \
@@ -297,6 +297,10 @@ cache_tagging_SOURCES = cache_tagging.c
 cache_tagging_OBJECTS = cache_tagging.$(OBJEXT)
 cache_tagging_LDADD = $(LDADD)
 cache_tagging_DEPENDENCIES = libh5test.la $(LIBHDF5)
+chunk_info_SOURCES = chunk_info.c
+chunk_info_OBJECTS = chunk_info.$(OBJEXT)
+chunk_info_LDADD = $(LDADD)
+chunk_info_DEPENDENCIES = libh5test.la $(LIBHDF5)
 cmpd_dset_SOURCES = cmpd_dset.c
 cmpd_dset_OBJECTS = cmpd_dset.$(OBJEXT)
 cmpd_dset_LDADD = $(LDADD)
@@ -313,6 +317,10 @@ dangle_SOURCES = dangle.c
 dangle_OBJECTS = dangle.$(OBJEXT)
 dangle_LDADD = $(LDADD)
 dangle_DEPENDENCIES = libh5test.la $(LIBHDF5)
+del_many_dense_attrs_SOURCES = del_many_dense_attrs.c
+del_many_dense_attrs_OBJECTS = del_many_dense_attrs.$(OBJEXT)
+del_many_dense_attrs_LDADD = $(LDADD)
+del_many_dense_attrs_DEPENDENCIES = libh5test.la $(LIBHDF5)
 direct_chunk_SOURCES = direct_chunk.c
 direct_chunk_OBJECTS = direct_chunk.$(OBJEXT)
 direct_chunk_LDADD = $(LDADD)
@@ -733,17 +741,18 @@ SOURCES = $(libfilter_plugin1_dsets_la_SOURCES) \
 	accum.c accum_swmr_reader.c app_ref.c atomic_reader.c \
 	atomic_writer.c big.c bittests.c btree2.c cache.c cache_api.c \
 	$(cache_image_SOURCES) cache_logging.c cache_tagging.c \
-	cmpd_dset.c cork.c cross_read.c dangle.c direct_chunk.c \
-	dsets.c dt_arith.c dtransform.c dtypes.c earray.c efc.c \
-	enc_dec_plist.c enc_dec_plist_cross_platform.c enum.c \
-	err_compat.c error_test.c evict_on_close.c extend.c external.c \
-	farray.c fheap.c file_image.c filenotclosed.c fillval.c \
-	filter_fail.c filter_plugin.c flush1.c flush2.c flushrefresh.c \
-	freespace.c gen_bad_offset.c gen_bad_ohdr.c gen_bogus.c \
-	gen_bounds.c gen_cross.c gen_deflate.c gen_file_image.c \
-	gen_filespace.c gen_filters.c gen_new_array.c gen_new_fill.c \
-	gen_new_group.c gen_new_mtime.c gen_new_super.c \
-	gen_noencoder.c gen_nullspace.c gen_plist.c gen_sizes_lheap.c \
+	chunk_info.c cmpd_dset.c cork.c cross_read.c dangle.c \
+	del_many_dense_attrs.c direct_chunk.c dsets.c dt_arith.c \
+	dtransform.c dtypes.c earray.c efc.c enc_dec_plist.c \
+	enc_dec_plist_cross_platform.c enum.c err_compat.c \
+	error_test.c evict_on_close.c extend.c external.c farray.c \
+	fheap.c file_image.c filenotclosed.c fillval.c filter_fail.c \
+	filter_plugin.c flush1.c flush2.c flushrefresh.c freespace.c \
+	gen_bad_offset.c gen_bad_ohdr.c gen_bogus.c gen_bounds.c \
+	gen_cross.c gen_deflate.c gen_file_image.c gen_filespace.c \
+	gen_filters.c gen_new_array.c gen_new_fill.c gen_new_group.c \
+	gen_new_mtime.c gen_new_super.c gen_noencoder.c \
+	gen_nullspace.c gen_plist.c gen_sizes_lheap.c \
 	gen_specmetaread.c gen_udlinks.c getname.c gheap.c hyperslab.c \
 	istore.c lheap.c links.c links_env.c mf.c mount.c mtime.c \
 	ntypes.c objcopy.c ohdr.c page_buffer.c pool.c reserved.c \
@@ -763,16 +772,17 @@ DIST_SOURCES = $(am__libfilter_plugin1_dsets_la_SOURCES_DIST) \
 	$(libh5test_la_SOURCES) accum.c accum_swmr_reader.c app_ref.c \
 	atomic_reader.c atomic_writer.c big.c bittests.c btree2.c \
 	cache.c cache_api.c $(cache_image_SOURCES) cache_logging.c \
-	cache_tagging.c cmpd_dset.c cork.c cross_read.c dangle.c \
-	direct_chunk.c dsets.c dt_arith.c dtransform.c dtypes.c \
-	earray.c efc.c enc_dec_plist.c enc_dec_plist_cross_platform.c \
-	enum.c err_compat.c error_test.c evict_on_close.c extend.c \
-	external.c farray.c fheap.c file_image.c filenotclosed.c \
-	fillval.c filter_fail.c filter_plugin.c flush1.c flush2.c \
-	flushrefresh.c freespace.c gen_bad_offset.c gen_bad_ohdr.c \
-	gen_bogus.c gen_bounds.c gen_cross.c gen_deflate.c \
-	gen_file_image.c gen_filespace.c gen_filters.c gen_new_array.c \
-	gen_new_fill.c gen_new_group.c gen_new_mtime.c gen_new_super.c \
+	cache_tagging.c chunk_info.c cmpd_dset.c cork.c cross_read.c \
+	dangle.c del_many_dense_attrs.c direct_chunk.c dsets.c \
+	dt_arith.c dtransform.c dtypes.c earray.c efc.c \
+	enc_dec_plist.c enc_dec_plist_cross_platform.c enum.c \
+	err_compat.c error_test.c evict_on_close.c extend.c external.c \
+	farray.c fheap.c file_image.c filenotclosed.c fillval.c \
+	filter_fail.c filter_plugin.c flush1.c flush2.c flushrefresh.c \
+	freespace.c gen_bad_offset.c gen_bad_ohdr.c gen_bogus.c \
+	gen_bounds.c gen_cross.c gen_deflate.c gen_file_image.c \
+	gen_filespace.c gen_filters.c gen_new_array.c gen_new_fill.c \
+	gen_new_group.c gen_new_mtime.c gen_new_super.c \
 	gen_noencoder.c gen_nullspace.c gen_plist.c gen_sizes_lheap.c \
 	gen_specmetaread.c gen_udlinks.c getname.c gheap.c hyperslab.c \
 	istore.c lheap.c links.c links_env.c mf.c mount.c mtime.c \
@@ -1013,9 +1023,8 @@ TEST_LOGS = $(am__test_logs2:.sh.log=.log)
 SH_LOG_DRIVER = $(SHELL) $(top_srcdir)/bin/test-driver
 SH_LOG_COMPILE = $(SH_LOG_COMPILER) $(AM_SH_LOG_FLAGS) $(SH_LOG_FLAGS)
 am__DIST_COMMON = $(srcdir)/H5srcdir_str.h.in $(srcdir)/Makefile.in \
-	$(srcdir)/test_filenotclosed.sh.in \
 	$(srcdir)/test_filter_plugin.sh.in \
-	$(srcdir)/test_usecases.sh.in \
+	$(srcdir)/test_usecases.sh.in $(srcdir)/testabort_fail.sh.in \
 	$(srcdir)/testcheck_version.sh.in $(srcdir)/testerror.sh.in \
 	$(srcdir)/testflushrefresh.sh.in $(srcdir)/testlibinfo.sh.in \
 	$(srcdir)/testlinks_env.sh.in $(srcdir)/testswmr.sh.in \
@@ -1164,7 +1173,6 @@ MAINT = @MAINT@
 MAKEINFO = @MAKEINFO@
 MANIFEST_TOOL = @MANIFEST_TOOL@
 MEMORYALLOCSANITYCHECK = @MEMORYALLOCSANITYCHECK@
-METADATATRACEFILE = @METADATATRACEFILE@
 MKDIR_P = @MKDIR_P@
 MPE = @MPE@
 NM = @NM@
@@ -1198,6 +1206,7 @@ PAC_FORTRAN_NUM_INTEGER_KINDS = @PAC_FORTRAN_NUM_INTEGER_KINDS@
 PARALLEL = @PARALLEL@
 PARALLEL_FILTERED_WRITES = @PARALLEL_FILTERED_WRITES@
 PATH_SEPARATOR = @PATH_SEPARATOR@
+PREADWRITE = @PREADWRITE@
 PROFILING = @PROFILING@
 RANLIB = @RANLIB@
 ROOT = @ROOT@
@@ -1358,10 +1367,12 @@ CHECK_CLEANFILES = *.chkexe *.chklog *.clog *.clog2 accum.h5 \
 	dls_01_strings.h5 extend.h5 istore.h5 extlinks*.h5 frspace.h5 \
 	links*.h5 sys_file1 tfile[1-7].h5 th5s[1-4].h5 lheap.h5 \
 	fheap.h5 ohdr.h5 stab.h5 extern_[1-5].h5 extern_[1-4][rw].raw \
-	gheap[0-4].h5 dt_arith[1-2] links.h5 links[0-6]*.h5 \
-	extlinks[0-15].h5 tmp big.data big[0-9][0-9][0-9][0-9][0-9].h5 \
-	stdio.h5 sec2.h5 dtypes[0-9].h5 dtypes1[0].h5 dt_arith[1-2].h5 \
-	tattr.h5 tselect.h5 mtime.h5 unlink.h5 unicode.h5 coord.h5 \
+	gheap[0-4].h5 ohdr_min_a.h5 ohdr_min_b.h5 \
+	min_dset_ohdr_testfile.h5 dt_arith[1-2] links.h5 \
+	links[0-6]*.h5 extlinks[0-15].h5 tmp big.data \
+	big[0-9][0-9][0-9][0-9][0-9].h5 stdio.h5 sec2.h5 \
+	dtypes[0-9].h5 dtypes1[0].h5 dt_arith[1-2].h5 tattr.h5 \
+	tselect.h5 mtime.h5 unlink.h5 unicode.h5 coord.h5 \
 	fillval_[0-9].h5 fillval.raw mount_[0-9].h5 testmeta.h5 \
 	ttime.h5 trefer[1-3].h5 tvltypes.h5 tvlstr.h5 tvlstr2.h5 \
 	twriteorder.dat flush.h5 flush-swmr.h5 noflush.h5 \
@@ -1400,24 +1411,24 @@ CHECK_CLEANFILES = *.chkexe *.chklog *.clog *.clog2 accum.h5 \
 #       testflushrefresh.sh: flushrefresh
 #       testswmr.sh: swmr*
 #       testvdsswmr.sh: vds_swmr*
-#       test_filenotclosed.sh: filenotclosed.c
+#       testabort_fail.sh: filenotclosed.c and del_many_dense_attrs.c
 #       test_filter_plugin.sh: filter_plugin.c
 #       test_usecases.sh: use_append_chunk, use_append_mchunks, use_disable_mdc_flushes
 TEST_SCRIPT = testerror.sh testlibinfo.sh testcheck_version.sh \
-	testlinks_env.sh test_filenotclosed.sh testswmr.sh \
-	testvdsswmr.sh testflushrefresh.sh test_usecases.sh \
+	testlinks_env.sh testswmr.sh testvdsswmr.sh \
+	testflushrefresh.sh test_usecases.sh testabort_fail.sh \
 	$(am__append_1)
 SCRIPT_DEPEND = error_test$(EXEEXT) err_compat$(EXEEXT) \
 	links_env$(EXEEXT) filenotclosed$(EXEEXT) \
-	flushrefresh$(EXEEXT) use_append_chunk$(EXEEXT) \
-	use_append_mchunks$(EXEEXT) use_disable_mdc_flushes$(EXEEXT) \
-	swmr_generator$(EXEEXT) swmr_reader$(EXEEXT) \
-	swmr_writer$(EXEEXT) swmr_remove_reader$(EXEEXT) \
-	swmr_remove_writer$(EXEEXT) swmr_addrem_writer$(EXEEXT) \
-	swmr_sparse_reader$(EXEEXT) swmr_sparse_writer$(EXEEXT) \
-	swmr_start_write$(EXEEXT) vds_swmr_gen$(EXEEXT) \
-	vds_swmr_reader$(EXEEXT) vds_swmr_writer$(EXEEXT) \
-	$(am__append_2)
+	del_many_dense_attrs$(EXEEXT) flushrefresh$(EXEEXT) \
+	use_append_chunk$(EXEEXT) use_append_mchunks$(EXEEXT) \
+	use_disable_mdc_flushes$(EXEEXT) swmr_generator$(EXEEXT) \
+	swmr_reader$(EXEEXT) swmr_writer$(EXEEXT) \
+	swmr_remove_reader$(EXEEXT) swmr_remove_writer$(EXEEXT) \
+	swmr_addrem_writer$(EXEEXT) swmr_sparse_reader$(EXEEXT) \
+	swmr_sparse_writer$(EXEEXT) swmr_start_write$(EXEEXT) \
+	vds_swmr_gen$(EXEEXT) vds_swmr_reader$(EXEEXT) \
+	vds_swmr_writer$(EXEEXT) $(am__append_2)
 check_SCRIPTS = $(TEST_SCRIPT)
 
 # These are our main targets. They should be listed in the order to be
@@ -1428,8 +1439,8 @@ TEST_PROG = testhdf5 \
            cache cache_api cache_image cache_tagging lheap ohdr stab gheap \
            evict_on_close farray earray btree2 fheap \
            pool accum hyperslab istore bittests dt_arith page_buffer \
-           dtypes dsets cmpd_dset filter_fail extend direct_chunk external efc \
-           objcopy links unlink twriteorder big mtime fillval mount \
+           dtypes dsets chunk_info cmpd_dset filter_fail extend direct_chunk \
+           external efc objcopy links unlink twriteorder big mtime fillval mount \
            flush1 flush2 app_ref enum set_extent ttsafe enc_dec_plist \
            enc_dec_plist_cross_platform getname vfd ntypes dangle dtransform \
            reserved cross_read freespace mf vds file_image unregister \
@@ -1487,7 +1498,7 @@ use_disable_mdc_flushes_SOURCES = use_disable_mdc_flushes.c
 
 # Temporary files.
 DISTCLEANFILES = testerror.sh testlibinfo.sh testcheck_version.sh testlinks_env.sh test_filter_plugin.sh \
-    testswmr.sh testvdsswmr.sh test_usecases.sh testflushrefresh.sh test_filenotclosed.sh
+    testswmr.sh testvdsswmr.sh test_usecases.sh testflushrefresh.sh testabort_fail.sh
 
 
 # Automake needs to be taught how to build lib, progs and tests targets.
@@ -1546,6 +1557,8 @@ $(ACLOCAL_M4): @MAINTAINER_MODE_TRUE@ $(am__aclocal_m4_deps)
 $(am__aclocal_m4_deps):
 H5srcdir_str.h: $(top_builddir)/config.status $(srcdir)/H5srcdir_str.h.in
 	cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@
+testabort_fail.sh: $(top_builddir)/config.status $(srcdir)/testabort_fail.sh.in
+	cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@
 testcheck_version.sh: $(top_builddir)/config.status $(srcdir)/testcheck_version.sh.in
 	cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@
 testerror.sh: $(top_builddir)/config.status $(srcdir)/testerror.sh.in
@@ -1560,8 +1573,6 @@ testswmr.sh: $(top_builddir)/config.status $(srcdir)/testswmr.sh.in
 	cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@
 testvdsswmr.sh: $(top_builddir)/config.status $(srcdir)/testvdsswmr.sh.in
 	cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@
-test_filenotclosed.sh: $(top_builddir)/config.status $(srcdir)/test_filenotclosed.sh.in
-	cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@
 test_filter_plugin.sh: $(top_builddir)/config.status $(srcdir)/test_filter_plugin.sh.in
 	cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@
 test_usecases.sh: $(top_builddir)/config.status $(srcdir)/test_usecases.sh.in
@@ -1663,6 +1674,10 @@ cache_tagging$(EXEEXT): $(cache_tagging_OBJECTS) $(cache_tagging_DEPENDENCIES) $
 	@rm -f cache_tagging$(EXEEXT)
 	$(AM_V_CCLD)$(LINK) $(cache_tagging_OBJECTS) $(cache_tagging_LDADD) $(LIBS)
 
+chunk_info$(EXEEXT): $(chunk_info_OBJECTS) $(chunk_info_DEPENDENCIES) $(EXTRA_chunk_info_DEPENDENCIES) 
+	@rm -f chunk_info$(EXEEXT)
+	$(AM_V_CCLD)$(LINK) $(chunk_info_OBJECTS) $(chunk_info_LDADD) $(LIBS)
+
 cmpd_dset$(EXEEXT): $(cmpd_dset_OBJECTS) $(cmpd_dset_DEPENDENCIES) $(EXTRA_cmpd_dset_DEPENDENCIES) 
 	@rm -f cmpd_dset$(EXEEXT)
 	$(AM_V_CCLD)$(LINK) $(cmpd_dset_OBJECTS) $(cmpd_dset_LDADD) $(LIBS)
@@ -1679,6 +1694,10 @@ dangle$(EXEEXT): $(dangle_OBJECTS) $(dangle_DEPENDENCIES) $(EXTRA_dangle_DEPENDE
 	@rm -f dangle$(EXEEXT)
 	$(AM_V_CCLD)$(LINK) $(dangle_OBJECTS) $(dangle_LDADD) $(LIBS)
 
+del_many_dense_attrs$(EXEEXT): $(del_many_dense_attrs_OBJECTS) $(del_many_dense_attrs_DEPENDENCIES) $(EXTRA_del_many_dense_attrs_DEPENDENCIES) 
+	@rm -f del_many_dense_attrs$(EXEEXT)
+	$(AM_V_CCLD)$(LINK) $(del_many_dense_attrs_OBJECTS) $(del_many_dense_attrs_LDADD) $(LIBS)
+
 direct_chunk$(EXEEXT): $(direct_chunk_OBJECTS) $(direct_chunk_DEPENDENCIES) $(EXTRA_direct_chunk_DEPENDENCIES) 
 	@rm -f direct_chunk$(EXEEXT)
 	$(AM_V_CCLD)$(LINK) $(direct_chunk_OBJECTS) $(direct_chunk_LDADD) $(LIBS)
@@ -2063,10 +2082,12 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/cache_image.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/cache_logging.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/cache_tagging.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/chunk_info.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/cmpd_dset.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/cork.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/cross_read.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/dangle.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/del_many_dense_attrs.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/direct_chunk.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/dsets.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/dt_arith.Po@am__quote@
@@ -2569,6 +2590,13 @@ dsets.log: dsets$(EXEEXT)
 	--log-file $$b.log --trs-file $$b.trs \
 	$(am__common_driver_flags) $(AM_LOG_DRIVER_FLAGS) $(LOG_DRIVER_FLAGS) -- $(LOG_COMPILE) \
 	"$$tst" $(AM_TESTS_FD_REDIRECT)
+chunk_info.log: chunk_info$(EXEEXT)
+	@p='chunk_info$(EXEEXT)'; \
+	b='chunk_info'; \
+	$(am__check_pre) $(LOG_DRIVER) --test-name "$$f" \
+	--log-file $$b.log --trs-file $$b.trs \
+	$(am__common_driver_flags) $(AM_LOG_DRIVER_FLAGS) $(LOG_DRIVER_FLAGS) -- $(LOG_COMPILE) \
+	"$$tst" $(AM_TESTS_FD_REDIRECT)
 cmpd_dset.log: cmpd_dset$(EXEEXT)
 	@p='cmpd_dset$(EXEEXT)'; \
 	b='cmpd_dset'; \
@@ -3228,7 +3256,7 @@ build-check-p: $(LIB) $(PROGS) $(chk_TESTS)
 	    echo "**** Hint ****";                                            \
 	    echo "Parallel test files reside in the current directory"        \
 	         "by default.";                                               \
-	    echo "Set HDF5_PARAPREFIX to use another directory. E.g.,";       \
+	    echo "Set HDF5_PARAPREFIX to use another directory. e.g.,";       \
 	    echo "    HDF5_PARAPREFIX=/PFS/user/me";                          \
 	    echo "    export HDF5_PARAPREFIX";                                \
 	    echo "    make check";                                            \
diff --git a/test/ShellTests.cmake b/test/ShellTests.cmake
index 58dc85d..98f3daf 100644
--- a/test/ShellTests.cmake
+++ b/test/ShellTests.cmake
@@ -171,6 +171,7 @@ if (UNIX)
     #    atomic_writer
     #    atomic_reader
     #    filenotclosed
+    #    del_many_dense_attrs
     #    flushrefresh
     ##############################################################################
     # autotools script tests
@@ -178,7 +179,7 @@ if (UNIX)
     # NOT CONVERTED accum_swmr_reader is used by accum.c.
     # NOT CONVERTED atomic_writer and atomic_reader are standalone programs.
     # links_env is used by testlinks_env.sh
-    # filenotclosed is used by test_filenotclosed.sh
+    # filenotclosed and del_many_dense_attrs are used by testabort_fail.sh
     # NOT CONVERTED flushrefresh is used by testflushrefresh.sh.
     # NOT CONVERTED use_append_chunk, use_append_mchunks and use_disable_mdc_flushes are used by test_usecases.sh
     # NOT CONVERTED swmr_* files (besides swmr.c) are used by testswmr.sh.
diff --git a/test/chunk_info.c b/test/chunk_info.c
index e3006cc..866fd68 100644
--- a/test/chunk_info.c
+++ b/test/chunk_info.c
@@ -15,23 +15,1532 @@
  * Programmer:  Pedro Vicente <pvn@hdfgroup.edu>
  *              April 7, 2008
  *
- * Purpose:     Tests the H5Dget_chunk_info API function
- *              This program writes a 4x4 dataset by iterating on 2x2 chunks
- *               at a time
+ * Purpose:     Tests chunk query API functions
+ *
+ * Modification:
+ *              Many tests were added for HDFFV-10615. -BMR, October 2018
+ *
+ * Test structure:
+ *          main()
+ *              test_get_chunk_info_highest18()
+ *              test_get_chunk_info_110()
+ *                  test_chunk_info_single_chunk()
+ *                  test_chunk_info_implicit()
+ *                  test_chunk_info_fixed_array()
+ *                  test_chunk_info_extensible_array()
+ *                  test_chunk_info_version2_btrees()
+ *
  */
+#define H5D_FRIEND
+#define H5D_TESTING     /* to use H5D__ functions */
+#include "H5Dpkg.h"
 
+#include "testhdf5.h"
 
-#include "h5test.h"
+/* Test file names */
+const char *FILENAME[] = {
+        "tchunk_info_18",
+        "tchunk_info_110",
+        "chunk_info",
+        NULL
+};
 
-#define PRINT_DATA
-#define H5FILE_NAME "chunk_info.h5"
+/* From original test */
 #define DATASETNAME "2d"
-#define RANK         2
 
+/* Parameters for testing chunk querying */
+#define RANK                    2
+#define FILENAME_BUF_SIZE       1024
+#define DSET_SIMPLE_CHUNKED     "Chunked Dataset"
+#define DSET_EMPTY              "Empty Dataset"
+#define DSET_EMPTY_ALLOC        "Empty Dataset with ALLOC_TIME_EARLY"
+#define DSET_SINGLE_CHUNK       "Single Chunk Index Dataset"
+#define DSET_IMPLICIT_INDEX     "Implicit Index Dataset"
+#define DSET_FIXED_ARR_INDEX    "Fixed Array Index Dataset"
+#define DSET_EXT_ARR_INDEX      "Extensible Array Index Dataset"
+#define DSET_V2_BTREE_INDEX     "Version 2 B-Tree Index Dataset"
+#define NX                      24
+#define NY                      16
+#define CHUNK_NX                6
+#define CHUNK_NY                4
+#define SINGLE_CHUNK_SIZE       (NX*NY*sizeof(int))
+#define CHUNK_SIZE              96
+#define NUM_CHUNKS              16
+#define NUM_CHUNKS_WRITTEN      4
+
+/* Artifact of original file, maybe removed */
+/* #define PRINT_DATA */
+
+/* Utility function to initialize arguments */
+void reinit_vars(unsigned *read_flt_msk, haddr_t *addr, hsize_t *size);
+
+/*-------------------------------------------------------------------------
+ * Function:    read_each_chunk (helper function)
+ *
+ * Purpose:     Reads the chunk specified by its offset and verifies that
+ *              it contains the same data as what was written.  This function
+ *              is used in test_get_chunk_info.
+ *
+ * Return:      Success:    SUCCEED
+ *              Failure:    FAIL
+ *
+ * Date:        September 2018
+ *
+ *-------------------------------------------------------------------------
+ */
+//EIP - May be this function should take a pointer to an array of chunk dimensions
+//EIP  and its size, so it is not restricted to 2 dims only?
+static herr_t read_each_chunk(hid_t dset_id, hsize_t offset1, hsize_t offset2, void *direct_buf)
+{
+    int      read_buf[CHUNK_NX][CHUNK_NY];
+    hsize_t  offset[2] = {offset1, offset2};
+    unsigned read_flt_msk = 0;
+    herr_t  ret;                        /* Return value */
+
+    HDmemset(&read_buf, 0, sizeof(read_buf));
+
+    /* Read the chunk specified by its offset */
+    ret = H5Dread_chunk(dset_id, H5P_DEFAULT, offset, &read_flt_msk, read_buf);
+    if(ret < 0) return(FAIL);
+
+    /* Verify that read chunk is the same as the corresponding written one */
+    if(HDmemcmp(direct_buf, read_buf, CHUNK_NX*CHUNK_NY) != 0)
+    {
+        HDfprintf(stderr, "Read chunk differs from written chunk at offset (%d,%d)\n", offset1, offset2);
+        return(FAIL);
+    }
+
+    return(SUCCEED);
+}
+
+/*-------------------------------------------------------------------------
+ * Function:    reinit_vars (helper function)
+ *
+ * Purpose:     Helper function to wipe out variables for the next use,
+ *              used in test_get_chunk_info.
+ *
+ * Return:      Won't fail
+ *
+ * Date:        September 2018
+ *
+ *-------------------------------------------------------------------------
+ */
+void reinit_vars(unsigned *read_flt_msk, haddr_t *addr, hsize_t *size)
+{
+    if(read_flt_msk)
+        *read_flt_msk = 0;
+    if(addr)
+        *addr = 0;
+    if(size)
+        *size = 0;
+}
 
-int main( void )
+/*-------------------------------------------------------------------------
+ * Function:	test_get_chunk_info_highest18
+ *
+ * Purpose:	    Test getting various chunk information
+ *
+ * Return:	    Success:	SUCCEED
+ *		        Failure:	FAIL
+ *
+ * Note:        Note that the dataspace argument in these new functions are
+ *              currently not used.  The functionality involved the dataspace
+ *              will be implemented in the next version.
+ *
+ * Description:
+ *              This function tests the new API functions added for EED-343:
+ *              H5Dget_num_chunks, H5Dget_chunk_info, and
+ *              H5Dget_chunk_info_by_coord for high bound up to 1.8.
+ *
+ * Date:        September 2018
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+test_get_chunk_info_highest18(hid_t fapl)
 {
+    char     filename[FILENAME_BUF_SIZE];
+    hid_t    chunkfile = -1;     /* File ID */
+    hid_t    dspace = -1;        /* Dataspace ID */
+    hid_t    dset = -1;          /* Dataset ID */
+    hid_t    cparms = -1;        /* Creation plist */
+    hsize_t  dims[2]  = {NX, NY};/* Dataset dimensions */
+    hsize_t  maxdims[2] = {H5S_UNLIMITED, H5S_UNLIMITED};
+    hsize_t  chunk_dims[2] = {CHUNK_NX, CHUNK_NY};      /* Chunk dimensions */
+    int      direct_buf[NUM_CHUNKS][CHUNK_NX][CHUNK_NY];/* Data in chunks */
+    int      out_buf[NX][NY];    /* Buffer to read data in */
+    size_t   buf_size = CHUNK_NX*CHUNK_NY*sizeof(int);  /* Buffer size of a chk */
+    unsigned filter_mask = 0;    /* Filter mask */
+    unsigned read_flt_msk = 0;   /* Filter mask after direct read */
+    int      fillvalue = -1;     /* Fill value */
+    int      aggression = 9;     /* Compression aggression setting */
+    H5F_libver_t low, high;      /* File format bounds */
+    hsize_t  offset[2];          /* Offset coordinates of a chunk */
+    hsize_t  out_offset[2] = {0, 0}; /* Buffer to get offset coordinates */
+    hsize_t  size = 0;           /* Size of an allocated/written chunk */
+    hsize_t  nchunks = 0;        /* Number of chunks */
+    haddr_t  addr = 0;           /* Address of an allocated/written chunk */
+    hsize_t  index = 0;          /* Index of a chunk */
+    int      n;                  /* Used on buffer, to avoid conversion warning */
+    hsize_t  i, j;
+    herr_t   ret;
+
+    TESTING("getting chunk information in file with version prior to 1.10");
+
+    /* Create the file */
+    h5_fixname(FILENAME[0], fapl, filename, sizeof filename);
+
+    /* Set high bound to V18 to test chunked dataset that use B-tree v1
+       structures to index chunks */
+    high = H5F_LIBVER_V18;
+
+    /* Low bound can be anything below 1.10, which was when the new chunk storage
+       was introduced */
+    low = H5F_LIBVER_EARLIEST;
+
+    /* Set version bounds for creating the file */
+    if(H5Pset_libver_bounds(fapl, low, high) < 0)
+        TEST_ERROR
+
+    chunkfile = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
+    if(chunkfile < 0)
+        TEST_ERROR
+
+    /* Create the file and memory dataspaces */
+    if((dspace = H5Screate_simple(RANK, dims, maxdims)) < 0)
+        TEST_ERROR
+
+    /* Set dset creation properties with chunking, compression, and fillvalue */
+    if((cparms = H5Pcreate(H5P_DATASET_CREATE)) < 0) TEST_ERROR
+    if(H5Pset_chunk(cparms, RANK, chunk_dims) < 0) TEST_ERROR
+
+#ifdef H5_HAVE_FILTER_DEFLATE
+    if(H5Pset_deflate(cparms, (unsigned)aggression) < 0) TEST_ERROR
+#endif /* end H5_HAVE_FILTER_DEFLATE */
+
+    /* Set fill value */
+    if(H5Pset_fill_value(cparms, H5T_NATIVE_INT, &fillvalue) < 0) TEST_ERROR
+
+    /* Create a new dataset using cparms creation properties */
+    dset = H5Dcreate2(chunkfile, DSET_SIMPLE_CHUNKED, H5T_NATIVE_INT, dspace, H5P_DEFAULT, cparms, H5P_DEFAULT);
+    if(dset < 0) TEST_ERROR
+
+    /* Indicate skipping the compression filter */
+    filter_mask = 0x00000001;
+
+    /* Initialize the array of chunk data for all NUM_CHUNKS chunks */
+    for(n = 0; n < NUM_CHUNKS; n++)
+        for(i = 0; i < CHUNK_NX; i++)
+            for(j = 0; j < CHUNK_NY; j++)
+                direct_buf[n][i][j] = n + 1;
+
+    /* Write only NUM_CHUNKS_WRITTEN chunks at the following logical coords:
+       (0,2) (0,3) (1,2) (1,3) */
+    n = 0;
+    for (i = 0; i < 2; i++)
+        for (j = 2; j < 4; j++, n++)
+        {
+            offset[0] = i * CHUNK_NX;
+            offset[1] = j * CHUNK_NY;
+            ret = H5Dwrite_chunk(dset, H5P_DEFAULT, filter_mask, offset, buf_size, (void*)direct_buf[n]);
+            if(ret < 0) TEST_ERROR
+        }
+
+    if(H5Fflush(dset, H5F_SCOPE_LOCAL) < 0)
+        goto error;
+
+    /* Close the dataset then... */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+
+    /* ...open it again to test the chunk query functions */
+    if((dset = H5Dopen2(chunkfile, DSET_SIMPLE_CHUNKED, H5P_DEFAULT)) < 0)
+        TEST_ERROR
+
+    /* Get and verify the number of chunks written */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+    if(nchunks != NUM_CHUNKS_WRITTEN) TEST_ERROR
+
+    /* Read the entire dataset back */
+    ret = H5Dread(dset, H5T_NATIVE_INT, dspace, dspace, H5P_DEFAULT, out_buf);
+    if(ret < 0) TEST_ERROR
+
+    /* Get and verify info of the first chunk */
+    index = 0;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    ret = H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 8) TEST_ERROR
+
+    /* Get and verify info of the second chunk */
+    index = 1;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    ret = H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 12) TEST_ERROR
+
+    /* Get and verify info of the third chunk */
+    index = 2;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    ret = H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+ 
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 6 || out_offset[1] != 8) TEST_ERROR
+
+    /* Get and verify info of the last chunk */
+    index = 3;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    ret = H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 6 || out_offset[1] != 12) TEST_ERROR
+
+    /* Attempt to get info of empty chunk and verify the returned address and size */
+    index = 5;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    ret = H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    /* Get info of the chunk at logical coordinates (0,2) */
+    offset[0] = 0;
+    offset[1] = 2 * CHUNK_NY;
+    ret = H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+
+    /* Get info of the chunk at logical coordinates (1,3) */
+    offset[0] = 1 * CHUNK_NX;
+    offset[1] = 3 * CHUNK_NY;
+    ret = H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+
+    /* Attempt to get info of empty chunks, verify the returned addr and size */
+    offset[0] = 0;
+    offset[1] = 0;
+    ret = H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    offset[0] = 3 * CHUNK_NX;
+    offset[1] = 3 * CHUNK_NY;
+    ret = H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    /* Read each chunk and verify the values */
+    n = 0;
+    for (i = 0; i < 2; i++)
+        for (j = 2; j < 4; j++, n++)
+            if(read_each_chunk(dset, i*CHUNK_NX, j*CHUNK_NY, (void*)direct_buf[n]) < 0)
+                TEST_ERROR
+
+    /* Close the first dataset */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+
+    /* Create an empty dataset and close it */
+    dset = H5Dcreate2(chunkfile, DSET_EMPTY, H5T_NATIVE_INT, dspace, H5P_DEFAULT, cparms, H5P_DEFAULT);
+    if(dset < 0) TEST_ERROR
+    if(H5Dclose(dset) < 0) TEST_ERROR
+
+    /* Reopen the empty dataset to verify the chunk query functions on it */
+    if((dset = H5Dopen2(chunkfile, DSET_EMPTY, H5P_DEFAULT)) < 0)
+        TEST_ERROR
+
+    /* Verify that the number of chunks is 0 */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+    if(nchunks != 0) TEST_ERROR
+
+    /* Attempt to get info of a chunk from an empty dataset, verify the
+       returned address and size */
+    index = 0;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    ret = H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    /* Attempt to get info of a chunk given its coords from an empty dataset,
+       verify the returned address and size */
+    offset[0] = 0;
+    offset[1] = 0;
+    ret = H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    if(H5Dclose(dset) < 0) TEST_ERROR
+
+    /************************************************************************
+     * Test empty dataset with H5P_ALLOC_TIME_EARLY                         *
+     ************************************************************************/
+
+    /* Set space allocation to early so that chunk query functions will
+       retrieve chunk information even though the dataset is empty */
+    if(H5Pset_alloc_time(cparms, H5D_ALLOC_TIME_EARLY) < 0)
+        TEST_ERROR
+
+    /* Create an empty dataset and close it */
+    dset = H5Dcreate2(chunkfile, DSET_EMPTY_ALLOC, H5T_NATIVE_INT, dspace, H5P_DEFAULT, cparms, H5P_DEFAULT);
+    if(dset < 0) TEST_ERROR
+    if(H5Dclose(dset) < 0) TEST_ERROR
+
+    /* Reopen the empty dataset to verify the chunk query functions on it */
+    if((dset = H5Dopen2(chunkfile, DSET_EMPTY_ALLOC, H5P_DEFAULT)) < 0)
+        TEST_ERROR
+
+    /* Verify that the number of chunks is NUM_CHUNKS */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+    if(nchunks != NUM_CHUNKS) TEST_ERROR
+
+    /* Attempt to get info of a chunk from an empty dataset, verify the
+       returned address and size */
+    index = 0;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    ret = H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+
+    /* Because of H5P_ALLOC_TIME_EARLY, addr cannot be HADDR_UNDEF and size not 0 */
+    if(addr == HADDR_UNDEF) TEST_ERROR
+    if(size == 0) TEST_ERROR
+
+    index = 10;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    ret = H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size);
+    if(ret < 0) TEST_ERROR
+
+    /* Because of H5P_ALLOC_TIME_EARLY, addr cannot be HADDR_UNDEF and size not 0 */
+    if(addr == HADDR_UNDEF) TEST_ERROR
+    if(size == 0) TEST_ERROR
+
+    /* Attempt to get info of a chunk given its coords from an empty dataset,
+       verify the returned address and size */
+    offset[0] = 0;
+    offset[1] = 0;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    /* Because of H5P_ALLOC_TIME_EARLY, addr cannot be HADDR_UNDEF and size not 0 */
+    if(addr == HADDR_UNDEF) TEST_ERROR
+    if(size == 0) TEST_ERROR
+
+    if(H5Dclose(dset) < 0) TEST_ERROR
+
+    /* Close/release resources. */
+    if(H5Sclose(dspace) < 0) TEST_ERROR
+    if(H5Pclose(cparms) < 0) TEST_ERROR
+    if(H5Fclose(chunkfile) < 0) TEST_ERROR
+
+    PASSED();
+    return SUCCEED;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Dclose(dset);
+        H5Sclose(dspace);
+        H5Pclose(cparms);
+        H5Fclose(chunkfile);
+    } H5E_END_TRY;
+
+    H5_FAILED();
+    return FAIL;
+} /* test_get_chunk_info_highest18() */
+
+/*-------------------------------------------------------------------------
+ * Function:	test_chunk_info_single_chunk
+ *
+ * Purpose:	    Test getting various chunk information when Single Chunk
+ *              index type is used
+ *
+ * Return:	    Success:	SUCCEED
+ *		        Failure:	FAIL
+ *
+ * Note:        Note that the dataspace argument in these new functions are
+ *              currently not used.  The functionality involved the dataspace
+ *              will be implemented in the next version.
+ *
+ * Date:        November 2018
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+test_chunk_info_single_chunk(char *filename, hid_t fapl)
+{
+    hid_t    chunkfile = -1;     /* File ID */
+    hid_t    dspace = -1;        /* Dataspace ID */
+    hid_t    dset = -1;          /* Dataset ID */
+    hid_t    cparms = -1;        /* Creation plist */
+    hsize_t  dims[2]  = {NX, NY};/* Dataset dimensions */
+    hsize_t  chunk_dims[2] = {NX, NY};      /* Chunk dimensions */
+    int      in_buf[NX][NY];     /* Input buffer */
+    unsigned filter_mask = 0;    /* Filter mask */
+    unsigned read_flt_msk = 0;   /* Filter mask after direct read */
+    H5D_chunk_index_t idx_type;  /* Dataset chunk index type */
+    hsize_t  offset[2];          /* Offset coordinates of a chunk */
+    hsize_t  out_offset[2] = {0, 0}; /* Buffer to get offset coordinates */
+    hsize_t  size = 0;           /* Size of an allocated/written chunk */
+    hsize_t  nchunks = 0;        /* Number of chunks */
+    haddr_t  addr = 0;           /* Address of an allocated/written chunk */
+    hsize_t  index = 0;          /* Index of a chunk */
+    int      i, j;
+
+    TESTING("   Single Chunk index");
+
+    /* Open the file for reading/writing */
+    if((chunkfile = H5Fopen(filename, H5F_ACC_RDWR, fapl)) < 0)
+        TEST_ERROR
+ 
+    /* Create dataspace */
+    if((dspace = H5Screate_simple(RANK, dims, NULL)) < 0)
+        TEST_ERROR
+
+    /* Enable chunking */
+    if((cparms = H5Pcreate(H5P_DATASET_CREATE)) < 0)
+        TEST_ERROR
+
+    if(H5Pset_chunk(cparms, RANK, chunk_dims) < 0)
+        TEST_ERROR
+
+    /* Create a new dataset using cparms creation properties */
+    dset = H5Dcreate2(chunkfile, DSET_SINGLE_CHUNK, H5T_NATIVE_INT, dspace, H5P_DEFAULT, cparms, H5P_DEFAULT);
+    if(dset < 0) TEST_ERROR
+
+    /* Ensure we're using the correct chunk indexing scheme */
+    if(H5D__layout_idx_type_test(dset, &idx_type) < 0)
+        TEST_ERROR
+    if(idx_type != H5D_CHUNK_IDX_SINGLE)
+        FAIL_PUTS_ERROR("should be using Single Chunk index type");
+
+    /* Close the dataset then... */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+
+    /* ...open it again to test the chunk query functions on a single empty
+       chunk */
+    if((dset = H5Dopen2(chunkfile, DSET_SINGLE_CHUNK, H5P_DEFAULT)) < 0)
+        TEST_ERROR
+
+    /* Get the number of chunks and verify that no chunk has been written */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+    if(nchunks != 0) TEST_ERROR
+
+    /* Initialize the array of chunk data for the single chunk */
+    for(i = 0; i < NX; i++)
+        for(j = 0; j < NY; j++)
+            in_buf[i][j] = (i*j);
+
+    /* Write the chunk */
+    if(H5Dwrite(dset, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, in_buf) < 0)
+        TEST_ERROR
+
+    /* Get and verify that one chunk had been written */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+    if(nchunks != 1) TEST_ERROR
+
+    /* Get and verify info of the first and only chunk */
+    index = 0;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != SINGLE_CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 0) TEST_ERROR
+
+    /* Get info of the chunk at logical coordinates (0,0) */
+    offset[0] = 0;
+    offset[1] = 0;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if (read_flt_msk != filter_mask) TEST_ERROR
+    if (size != SINGLE_CHUNK_SIZE) TEST_ERROR
+
+    /* Release resourse */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+    if(H5Sclose(dspace) < 0) TEST_ERROR
+    if(H5Fclose(chunkfile) < 0) TEST_ERROR
+
+    PASSED();
+    return SUCCEED;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Dclose(dset);
+        H5Sclose(dspace);
+        H5Pclose(cparms);
+        H5Fclose(chunkfile);
+    } H5E_END_TRY;
+
+    H5_FAILED();
+    return FAIL;
+} /* test_chunk_info_single_chunk() */
+        
+/*-------------------------------------------------------------------------
+ * Function:	test_chunk_info_implicit
+ *
+ * Purpose:	    Test getting various chunk information when Implicit
+ *              index type is used
+ *
+ * Return:	    Success:	SUCCEED
+ *		        Failure:	FAIL
+ *
+ * Note:        Note that the dataspace argument in these new functions are
+ *              currently not used.  The functionality involved the dataspace
+ *              will be implemented in the next version.
+ *
+ * Date:        November 2018
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+test_chunk_info_implicit(char *filename, hid_t fapl)
+{
+    hid_t    chunkfile = -1;     /* File ID */
+    hid_t    dspace = -1;        /* Dataspace ID */
+    hid_t    dset = -1;          /* Dataset ID */
+    hid_t    cparms = -1;        /* Creation plist */
+    hsize_t  dims[2]  = {NX, NY};/* Dataset dimensions */
+    hsize_t  chunk_dims[2] = {CHUNK_NX, CHUNK_NY};      /* Chunk dimensions */
+    int      direct_buf[NUM_CHUNKS][CHUNK_NX][CHUNK_NY];/* Data in chunks */
+    int      out_buf[NX][NY];    /* Buffer to read data in */
+    size_t   buf_size = CHUNK_NX*CHUNK_NY*sizeof(int);  /* Buffer size of a chk */
+    unsigned filter_mask = 0;    /* Filter mask */
+    unsigned read_flt_msk = 0;   /* Filter mask after direct read */
+    H5D_chunk_index_t idx_type;  /* Dataset chunk index type */
+    hsize_t  offset[2];          /* Offset coordinates of a chunk */
+    hsize_t  out_offset[2] = {0, 0}; /* Buffer to get offset coordinates */
+    hsize_t  size = 0;           /* Size of an allocated/written chunk */
+    hsize_t  nchunks = 0;        /* Number of chunks */
+    haddr_t  addr = 0;           /* Address of an allocated/written chunk */
+    hsize_t  index = 0;          /* Index of a chunk */
+    int      n;                  /* Used on buffer, to avoid conversion warning */
+    hsize_t  i, j;
+    herr_t   ret;
+
+    TESTING("   Implicit index");
+
+    /* Open the file for reading/writing */
+    if((chunkfile = H5Fopen(filename, H5F_ACC_RDWR, fapl)) < 0)
+        TEST_ERROR
+ 
+    /* Create dataspace */
+    if((dspace = H5Screate_simple(RANK, dims, NULL)) < 0)
+        TEST_ERROR
+
+    /* Enable chunking */
+    if((cparms = H5Pcreate(H5P_DATASET_CREATE)) < 0)
+        TEST_ERROR
+
+    if(H5Pset_chunk(cparms, RANK, chunk_dims) < 0)
+        TEST_ERROR
+
+    if(H5Pset_alloc_time(cparms, H5D_ALLOC_TIME_EARLY) < 0)
+        TEST_ERROR
+
+    /* Create a new dataset using cparms creation properties */
+    dset = H5Dcreate2(chunkfile, DSET_IMPLICIT_INDEX, H5T_NATIVE_INT, dspace, H5P_DEFAULT, cparms, H5P_DEFAULT);
+    if(dset < 0) TEST_ERROR
+
+    /* Ensure we're using the correct chunk indexing scheme */
+    if(H5D__layout_idx_type_test(dset, &idx_type) < 0)
+        TEST_ERROR
+    if(idx_type != H5D_CHUNK_IDX_NONE) /* Implicit: No Index */
+        FAIL_PUTS_ERROR("should be using Implicit index type");
+
+    /* Close the dataset then... */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+
+    /* ...open it again to test the chunk query functions */
+    if((dset = H5Dopen2(chunkfile, DSET_IMPLICIT_INDEX, H5P_DEFAULT)) < 0)
+        TEST_ERROR
+
+    /* Get and verify the number of chunks */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+
+    /* All chunks because of H5D_ALLOC_TIME_EARLY */
+    if(nchunks != NUM_CHUNKS) TEST_ERROR
+
+    /* Initialize the array of chunk data for all NUM_CHUNKS chunks */
+    for(n = 0; n < NUM_CHUNKS; n++)
+        for(i = 0; i < CHUNK_NX; i++)
+            for(j = 0; j < CHUNK_NY; j++)
+                direct_buf[n][i][j] = n + 1;
+
+    /* Write only NUM_CHUNKS_WRITTEN chunks at the following logical coords:
+       (0,2) (0,3) (1,2) (1,3) */
+    n = 0;
+    for (i = 0; i < 2; i++)
+        for (j = 2; j < 4; j++, n++)
+        {
+            offset[0] = i * CHUNK_NX;
+            offset[1] = j * CHUNK_NY;
+            ret = H5Dwrite_chunk(dset, H5P_DEFAULT, filter_mask, offset, buf_size, (void*)direct_buf[n]);
+            if(ret < 0) TEST_ERROR
+        }
+
+    /* Get and verify the number of chunks written */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+
+    /* Should still be all chunks, because of H5D_ALLOC_TIME_EARLY */
+    if(nchunks != NUM_CHUNKS) TEST_ERROR
+
+    /* Read the entire dataset back */
+    if(H5Dread(dset, H5T_NATIVE_INT, dspace, dspace, H5P_DEFAULT, out_buf) < 0)
+        TEST_ERROR
+
+    /* Get and verify info of the first chunk */
+    index = 0;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 0) TEST_ERROR
+
+    /* Get and verify info of the second chunk */
+    index = 1;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 4) TEST_ERROR
+
+    /* Get and verify info of the third chunk */
+    index = 2;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+ 
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 8) TEST_ERROR
+
+    /* Get and verify info of the last chunk */
+    index = 3;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 12) TEST_ERROR
+
+    /* Attempt to get info of empty chunk and verify the returned address and size */
+    index = 5;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(addr == HADDR_UNDEF) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 6 || out_offset[1] != 4) TEST_ERROR
+
+    /* Get info of the chunk at logical coordinates (0,2) */
+    offset[0] = 0;
+    offset[1] = 2 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+
+    /* Get info of the chunk at logical coordinates (1,3) */
+    offset[0] = 1 * CHUNK_NX;
+    offset[1] = 3 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+
+    /* Attempt to get info of empty chunks, verify the returned address and size */
+    offset[0] = 0;
+    offset[1] = 0;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    /* Because of H5P_ALLOC_TIME_EARLY, addr cannot be HADDR_UNDEF */
+    if(addr == HADDR_UNDEF) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+
+    offset[0] = 3 * CHUNK_NX;
+    offset[1] = 3 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    /* Because of H5P_ALLOC_TIME_EARLY, addr cannot be HADDR_UNDEF */
+    if(addr == HADDR_UNDEF) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+
+    /* Read each chunk and verify the values */
+    n = 0;
+    for (i = 0; i < 2; i++)
+        for (j = 2; j < 4; j++, n++)
+            if(read_each_chunk(dset, i*CHUNK_NX, j*CHUNK_NY, (void*)direct_buf[n]) < 0)
+                TEST_ERROR
+
+    /* Release resourse */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+    if(H5Sclose(dspace) < 0) TEST_ERROR
+    if(H5Fclose(chunkfile) < 0) TEST_ERROR
+
+    PASSED();
+    return SUCCEED;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Dclose(dset);
+        H5Sclose(dspace);
+        H5Pclose(cparms);
+        H5Fclose(chunkfile);
+    } H5E_END_TRY;
+
+    H5_FAILED();
+    return FAIL;
+} /* test_chunk_info_implicit() */
+        
+/*-------------------------------------------------------------------------
+ * Function:	test_chunk_info_fixed_array
+ *
+ * Purpose:	    Test getting various chunk information when Fixed Array
+ *              index type is used
+ *
+ * Return:	    Success:	SUCCEED
+ *		        Failure:	FAIL
+ *
+ * Note:        Note that the dataspace argument in these new functions are
+ *              currently not used.  The functionality involved the dataspace
+ *              will be implemented in the next version.
+ *
+ * Date:        November 2018
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+test_chunk_info_fixed_array(char *filename, hid_t fapl)
+{
+    hid_t    chunkfile = -1;     /* File ID */
+    hid_t    dspace = -1;        /* Dataspace ID */
+    hid_t    dset = -1;          /* Dataset ID */
+    hid_t    cparms = -1;        /* Creation plist */
+    hsize_t  dims[2]  = {NX, NY};/* Dataset dimensions */
+    hsize_t  chunk_dims[2] = {CHUNK_NX, CHUNK_NY};      /* Chunk dimensions */
+    int      direct_buf[NUM_CHUNKS][CHUNK_NX][CHUNK_NY];/* Data in chunks */
+    int      out_buf[NX][NY];    /* Buffer to read data in */
+    size_t   buf_size = CHUNK_NX*CHUNK_NY*sizeof(int);  /* Buffer size of a chk */
+    unsigned filter_mask = 0;    /* Filter mask */
+    unsigned read_flt_msk = 0;   /* Filter mask after direct read */
+    H5D_chunk_index_t idx_type;  /* Dataset chunk index type */
+    hsize_t  offset[2];          /* Offset coordinates of a chunk */
+    hsize_t  out_offset[2] = {0, 0}; /* Buffer to get offset coordinates */
+    hsize_t  size = 0;           /* Size of an allocated/written chunk */
+    hsize_t  nchunks = 0;        /* Number of chunks */
+    haddr_t  addr = 0;           /* Address of an allocated/written chunk */
+    hsize_t  index = 0;          /* Index of a chunk */
+    int      n;                  /* Used on buffer, to avoid conversion warning */
+    hsize_t  i, j;
+    herr_t   ret;
+
+    TESTING("   Fixed Array index");
+
+    /* Open the file for reading/writing */
+    if((chunkfile = H5Fopen(filename, H5F_ACC_RDWR, fapl)) < 0)
+        TEST_ERROR
+ 
+    /* Create dataspace */
+    if((dspace = H5Screate_simple(RANK, dims, NULL)) < 0)
+        TEST_ERROR
+
+    /* Enable chunking */
+    if((cparms = H5Pcreate(H5P_DATASET_CREATE)) < 0)
+        TEST_ERROR
+
+    if(H5Pset_chunk(cparms, RANK, chunk_dims) < 0)
+        TEST_ERROR
+
+    /* Create a new dataset using cparms creation properties */
+    dset = H5Dcreate2(chunkfile, DSET_FIXED_ARR_INDEX, H5T_NATIVE_INT, dspace, H5P_DEFAULT, cparms, H5P_DEFAULT);
+    if(dset < 0) TEST_ERROR
 
+    /* Ensure we're using the correct chunk indexing scheme */
+    if(H5D__layout_idx_type_test(dset, &idx_type) < 0)
+        TEST_ERROR
+    if(idx_type != H5D_CHUNK_IDX_FARRAY)
+        FAIL_PUTS_ERROR("should be using Fixed Array index type");
+
+    /* Close the dataset then... */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+
+    /* ...open it again to test the chunk query functions */
+    if((dset = H5Dopen2(chunkfile, DSET_FIXED_ARR_INDEX, H5P_DEFAULT)) < 0)
+        TEST_ERROR
+
+    /* Get the number of chunks and verify that no chunk has been written */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+    if(nchunks != 0) TEST_ERROR
+
+    /* Initialize the array of chunk data for all NUM_CHUNKS chunks */
+    for(n = 0; n < NUM_CHUNKS; n++)
+        for(i = 0; i < CHUNK_NX; i++)
+            for(j = 0; j < CHUNK_NY; j++)
+                direct_buf[n][i][j] = n + 1;
+
+    /* Write only NUM_CHUNKS_WRITTEN chunks at the following logical coords:
+       (0,2) (0,3) (1,2) (1,3) */
+    n = 0;
+    for (i = 0; i < 2; i++)
+        for (j = 2; j < 4; j++, n++)
+        {
+            offset[0] = i * CHUNK_NX;
+            offset[1] = j * CHUNK_NY;
+            ret = H5Dwrite_chunk(dset, H5P_DEFAULT, filter_mask, offset, buf_size, (void*)direct_buf[n]);
+            if(ret < 0) TEST_ERROR
+        }
+
+    /* Read the entire dataset back */
+    if(H5Dread(dset, H5T_NATIVE_INT, dspace, dspace, H5P_DEFAULT, out_buf) < 0)
+        TEST_ERROR
+
+    /* Get and verify the number of chunks written */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+    if(nchunks != NUM_CHUNKS_WRITTEN) TEST_ERROR
+
+    /* Get and verify info of the first chunk */
+    index = 0;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 8) TEST_ERROR
+
+    /* Get and verify info of the second chunk */
+    index = 1;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 12) TEST_ERROR
+
+    /* Get and verify info of the third chunk */
+    index = 2;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 6 || out_offset[1] != 8) TEST_ERROR
+
+    /* Get and verify info of the last chunk */
+    index = 3;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 6 || out_offset[1] != 12) TEST_ERROR
+
+    /* Attempt to get info of empty chunk and verify the returned address and size */
+    index = 5;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    /* Get info of the chunk at logical coordinates (0,2) */
+    offset[0] = 0;
+    offset[1] = 2 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+
+    /* Get info of the chunk at logical coordinates (1,3) */
+    offset[0] = 1 * CHUNK_NX;
+    offset[1] = 3 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+
+    /* Attempt to get info of empty chunks, verify the returned address and size */
+    offset[0] = 0;
+    offset[1] = 0;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    offset[0] = 3 * CHUNK_NX;
+    offset[1] = 3 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    /* Read each chunk and verify the values */
+    n = 0;
+    for (i = 0; i < 2; i++)
+        for (j = 2; j < 4; j++, n++)
+            if(read_each_chunk(dset, i*CHUNK_NX, j*CHUNK_NY, (void*)direct_buf[n]) < 0)
+                TEST_ERROR
+
+    /* Release resourse */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+    if(H5Sclose(dspace) < 0) TEST_ERROR
+    if(H5Fclose(chunkfile) < 0) TEST_ERROR
+
+    PASSED();
+    return SUCCEED;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Dclose(dset);
+        H5Sclose(dspace);
+        H5Pclose(cparms);
+        H5Fclose(chunkfile);
+    } H5E_END_TRY;
+
+    H5_FAILED();
+    return FAIL;
+} /* test_chunk_info_fixed_array() */
+        
+/*-------------------------------------------------------------------------
+ * Function:	test_chunk_info_extensible_array
+ *
+ * Purpose:	    Test getting various chunk information when Extensible Array
+ *              index type is used
+ *
+ * Return:	    Success:	SUCCEED
+ *		        Failure:	FAIL
+ *
+ * Note:        Note that the dataspace argument in these new functions are
+ *              currently not used.  The functionality involved the dataspace
+ *              will be implemented in the next version.
+ *
+ * Date:        November 2018
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+test_chunk_info_extensible_array(char *filename, hid_t fapl)
+{
+    hid_t    chunkfile = -1;     /* File ID */
+    hid_t    dspace = -1;        /* Dataspace ID */
+    hid_t    dset = -1;          /* Dataset ID */
+    hid_t    cparms = -1;        /* Creation plist */
+    hsize_t  dims[2]  = {NX, NY};/* Dataset dimensions */
+    hsize_t  chunk_dims[2] = {CHUNK_NX, CHUNK_NY};      /* Chunk dimensions */
+    hsize_t  maxdims[2] = {H5S_UNLIMITED, NY}; /* One unlimited dimension */
+    int      direct_buf[NUM_CHUNKS][CHUNK_NX][CHUNK_NY];/* Data in chunks */
+    int      out_buf[NX][NY];    /* Buffer to read data in */
+    size_t   buf_size = CHUNK_NX*CHUNK_NY*sizeof(int);  /* Buffer size of a chk */
+    unsigned filter_mask = 0;    /* Filter mask */
+    unsigned read_flt_msk = 0;   /* Filter mask after direct read */
+    H5D_chunk_index_t idx_type;  /* Dataset chunk index type */
+    hsize_t  offset[2];          /* Offset coordinates of a chunk */
+    hsize_t  out_offset[2] = {0, 0}; /* Buffer to get offset coordinates */
+    hsize_t  size = 0;           /* Size of an allocated/written chunk */
+    hsize_t  nchunks = 0;        /* Number of chunks */
+    haddr_t  addr = 0;           /* Address of an allocated/written chunk */
+    hsize_t  index = 0;          /* Index of a chunk */
+    int      n;                  /* Used on buffer, to avoid conversion warning */
+    hsize_t  i, j;
+    herr_t   ret;
+
+    TESTING("   Extensible Array index");
+
+    /* Open the file for reading/writing */
+    if((chunkfile = H5Fopen(filename, H5F_ACC_RDWR, fapl)) < 0)
+        TEST_ERROR
+ 
+    /* Create dataspace */
+    if((dspace = H5Screate_simple(RANK, dims, maxdims)) < 0)
+        TEST_ERROR
+
+    /* Enable chunking */
+    if((cparms = H5Pcreate(H5P_DATASET_CREATE)) < 0)
+        TEST_ERROR
+
+    if(H5Pset_chunk(cparms, RANK, chunk_dims) < 0)
+        TEST_ERROR
+
+    /* Create a new dataset using cparms creation properties */
+    dset = H5Dcreate2(chunkfile, DSET_EXT_ARR_INDEX, H5T_NATIVE_INT, dspace, H5P_DEFAULT, cparms, H5P_DEFAULT);
+    if(dset < 0) TEST_ERROR
+
+    /* Ensure we're using the correct chunk indexing scheme */
+    if(H5D__layout_idx_type_test(dset, &idx_type) < 0)
+        TEST_ERROR
+    if(idx_type != H5D_CHUNK_IDX_EARRAY)
+        FAIL_PUTS_ERROR("should be using Extensible Array index type");
+
+    /* Close the dataset then... */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+
+    /* ...open it again to test the chunk query functions */
+    if((dset = H5Dopen2(chunkfile, DSET_EXT_ARR_INDEX, H5P_DEFAULT)) < 0)
+        TEST_ERROR
+
+    /* Get the number of chunks and verify that no chunk has been written */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+    if(nchunks != 0) TEST_ERROR
+
+    /* Initialize the array of chunk data for all NUM_CHUNKS chunks */
+    for(n = 0; n < NUM_CHUNKS; n++)
+        for(i = 0; i < CHUNK_NX; i++)
+            for(j = 0; j < CHUNK_NY; j++)
+                direct_buf[n][i][j] = n + 1;
+
+    /* Write only NUM_CHUNKS_WRITTEN chunks at the following logical coords:
+       (0,2) (0,3) (1,2) (1,3) */
+    n = 0;
+    for (i = 0; i < 2; i++)
+        for (j = 2; j < 4; j++, n++)
+        {
+            offset[0] = i * CHUNK_NX;
+            offset[1] = j * CHUNK_NY;
+            ret = H5Dwrite_chunk(dset, H5P_DEFAULT, filter_mask, offset, buf_size, (void*)direct_buf[n]);
+            if(ret < 0) TEST_ERROR
+        }
+
+    /* Get and verify the number of chunks written */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+    if(nchunks != NUM_CHUNKS_WRITTEN) TEST_ERROR
+
+    /* Get and verify info of the first chunk */
+    index = 0;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 8) TEST_ERROR
+
+    /* Get and verify info of the second chunk */
+    index = 1;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 12) TEST_ERROR
+
+    /* Get and verify info of the third chunk */
+    index = 2;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+ 
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 6 || out_offset[1] != 8) TEST_ERROR
+
+    /* Get and verify info of the last chunk */
+    index = 3;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 6 || out_offset[1] != 12) TEST_ERROR
+
+    /* Attempt to get info of empty chunk and verify the returned address and size */
+    index = 5;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    /* Get info of the chunk at logical coordinates (0,2) */
+    offset[0] = 0;
+    offset[1] = 2 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+
+    /* Get info of the chunk at logical coordinates (1,3) */
+    offset[0] = 1 * CHUNK_NX;
+    offset[1] = 3 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+
+    /* Attempt to get info of empty chunks, verify the returned address and size */
+    offset[0] = 0;
+    offset[1] = 0;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    offset[0] = 3 * CHUNK_NX;
+    offset[1] = 3 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    /* Read each chunk and verify the values */
+    n = 0;
+    for (i = 0; i < 2; i++)
+        for (j = 2; j < 4; j++, n++)
+            if(read_each_chunk(dset, i*CHUNK_NX, j*CHUNK_NY, (void*)direct_buf[n]) < 0)
+                TEST_ERROR
+
+    /* Release resourse */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+    if(H5Sclose(dspace) < 0) TEST_ERROR
+    if(H5Fclose(chunkfile) < 0) TEST_ERROR
+
+    PASSED();
+    return SUCCEED;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Dclose(dset);
+        H5Sclose(dspace);
+        H5Pclose(cparms);
+        H5Fclose(chunkfile);
+    } H5E_END_TRY;
+
+    H5_FAILED();
+    return FAIL;
+} /* test_chunk_info_extensible_array() */
+
+/*-------------------------------------------------------------------------
+ * Function:	test_chunk_info_version2_btrees
+ *
+ * Purpose:	    Test getting various chunk information when Version 2 B-trees
+ *              index type is used
+ *
+ * Return:	    Success:	SUCCEED
+ *		        Failure:	FAIL
+ *
+ * Note:        Note that the dataspace argument in these new functions are
+ *              currently not used.  The functionality involved the dataspace
+ *              will be implemented in the next version.
+ *
+ * Date:        November 2018
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+test_chunk_info_version2_btrees(char *filename, hid_t fapl)
+{
+    hid_t    chunkfile = -1;     /* File ID */
+    hid_t    dspace = -1;        /* Dataspace ID */
+    hid_t    dset = -1;          /* Dataset ID */
+    hid_t    cparms = -1;        /* Creation plist */
+    hsize_t  dims[2]  = {NX, NY};/* Dataset dimensions */
+    hsize_t  chunk_dims[2] = {CHUNK_NX, CHUNK_NY};      /* Chunk dimensions */
+    hsize_t  maxdims[2] = {H5S_UNLIMITED, H5S_UNLIMITED}; /* Two unlimited dims */
+    int      direct_buf[NUM_CHUNKS][CHUNK_NX][CHUNK_NY];/* Data in chunks */
+    int      out_buf[NX][NY];    /* Buffer to read data in */
+    size_t   buf_size = CHUNK_NX*CHUNK_NY*sizeof(int);  /* Buffer size of a chk */
+    unsigned filter_mask = 0;    /* Filter mask */
+    unsigned read_flt_msk = 0;   /* Filter mask after direct read */
+    H5D_chunk_index_t idx_type;  /* Dataset chunk index type */
+    hsize_t  offset[2];          /* Offset coordinates of a chunk */
+    hsize_t  out_offset[2] = {0, 0}; /* Buffer to get offset coordinates */
+    hsize_t  size = 0;           /* Size of an allocated/written chunk */
+    hsize_t  nchunks = 0;        /* Number of chunks */
+    haddr_t  addr = 0;           /* Address of an allocated/written chunk */
+    hsize_t  index = 0;          /* Index of a chunk */
+    int      n;                  /* Used on buffer, to avoid conversion warning */
+    hsize_t  i, j;
+    herr_t   ret;
+
+    TESTING("   Version 2 B-trees index");
+
+    /* Open the file for reading/writing */
+    if((chunkfile = H5Fopen(filename, H5F_ACC_RDWR, fapl)) < 0)
+        TEST_ERROR
+ 
+    /* Create dataspace */
+    if((dspace = H5Screate_simple(RANK, dims, maxdims)) < 0)
+        TEST_ERROR
+
+    /* Enable chunking */
+    if((cparms = H5Pcreate(H5P_DATASET_CREATE)) < 0)
+        TEST_ERROR
+
+    if(H5Pset_chunk(cparms, RANK, chunk_dims) < 0)
+        TEST_ERROR
+
+    /* Create a new dataset using cparms creation properties */
+    dset = H5Dcreate2(chunkfile, DSET_V2_BTREE_INDEX, H5T_NATIVE_INT, dspace, H5P_DEFAULT, cparms, H5P_DEFAULT);
+    if(dset < 0) TEST_ERROR
+
+    /* Ensure we're using the correct chunk indexing scheme */
+    if(H5D__layout_idx_type_test(dset, &idx_type) < 0)
+        TEST_ERROR
+    if(idx_type != H5D_CHUNK_IDX_BT2)
+        FAIL_PUTS_ERROR("should be using Version 2 B-tree index type");
+
+    /* Close the dataset then... */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+
+    /* ...open it again to test the chunk query functions */
+    if((dset = H5Dopen2(chunkfile, DSET_V2_BTREE_INDEX, H5P_DEFAULT)) < 0)
+        TEST_ERROR
+
+    /* Get the number of chunks and verify that no chunk has been written */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+    if(nchunks != 0) TEST_ERROR
+
+    /* Initialize the array of chunk data for all NUM_CHUNKS chunks */
+    for(n = 0; n < NUM_CHUNKS; n++)
+        for(i = 0; i < CHUNK_NX; i++)
+            for(j = 0; j < CHUNK_NY; j++)
+                direct_buf[n][i][j] = n + 1;
+
+    /* Write only NUM_CHUNKS_WRITTEN chunks at the following logical coords:
+       (0,2) (0,3) (1,2) (1,3) */
+    n = 0;
+    for (i = 0; i < 2; i++)
+        for (j = 2; j < 4; j++, n++)
+        {
+            offset[0] = i * CHUNK_NX;
+            offset[1] = j * CHUNK_NY;
+            ret = H5Dwrite_chunk(dset, H5P_DEFAULT, filter_mask, offset, buf_size, (void*)direct_buf[n]);
+            if(ret < 0) TEST_ERROR
+        }
+
+    /* Get and verify the number of chunks written */
+    if(H5Dget_num_chunks(dset, dspace, &nchunks) < 0) TEST_ERROR
+    if(nchunks != NUM_CHUNKS_WRITTEN) TEST_ERROR
+
+    /* Get and verify info of the first chunk */
+    index = 0;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 8) TEST_ERROR
+
+    /* Get and verify info of the second chunk */
+    index = 1;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 0 || out_offset[1] != 12) TEST_ERROR
+
+    /* Get and verify info of the third chunk */
+    index = 2;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+ 
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 6 || out_offset[1] != 8) TEST_ERROR
+
+    /* Get and verify info of the last chunk */
+    index = 3;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+    if(out_offset[0] != 6 || out_offset[1] != 12) TEST_ERROR
+
+    /* Attempt to get info of empty chunk and verify the returned address and size */
+    index = 5;
+    reinit_vars(&read_flt_msk, &addr, &size);
+    out_offset[0] = out_offset[1] = 0;
+    if(H5Dget_chunk_info(dset, dspace, index, out_offset, &read_flt_msk, &addr, &size) < 0)
+        TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    /* Get info of the chunk at logical coordinates (0,2) */
+    offset[0] = 0;
+    offset[1] = 2 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+
+    /* Get info of the chunk at logical coordinates (1,3) */
+    offset[0] = 1 * CHUNK_NX;
+    offset[1] = 3 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(read_flt_msk != filter_mask) TEST_ERROR
+    if(size != CHUNK_SIZE) TEST_ERROR
+
+    /* Attempt to get info of empty chunks, verify the returned address and size */
+    offset[0] = 0;
+    offset[1] = 0;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    offset[0] = 3 * CHUNK_NX;
+    offset[1] = 3 * CHUNK_NY;
+    if(H5Dget_chunk_info_by_coord(dset, offset, &read_flt_msk, &addr, &size) < 0) TEST_ERROR
+    if(addr != HADDR_UNDEF) TEST_ERROR
+    if(size != 0) TEST_ERROR
+
+    /* Read each chunk and verify the values */
+    n = 0;
+    for (i = 0; i < 2; i++)
+        for (j = 2; j < 4; j++, n++)
+            if(read_each_chunk(dset, i*CHUNK_NX, j*CHUNK_NY, (void*)direct_buf[n]) < 0)
+                TEST_ERROR
+
+    /* Release resourse */
+    if(H5Dclose(dset) < 0) TEST_ERROR
+    if(H5Sclose(dspace) < 0) TEST_ERROR
+    if(H5Fclose(chunkfile) < 0) TEST_ERROR
+
+    PASSED();
+    return SUCCEED;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Dclose(dset);
+        H5Sclose(dspace);
+        H5Pclose(cparms);
+        H5Fclose(chunkfile);
+    } H5E_END_TRY;
+
+    H5_FAILED();
+    return FAIL;
+} /* test_chunk_info_version2_btrees() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	test_get_chunk_info_110
+ *
+ * Purpose:	    Test getting various chunk information in version 1.10.
+ *
+ * Return:	    Success:	SUCCEED
+ *		        Failure:	FAIL
+ *
+ * Note:        Note that the dataspace argument in these new functions are
+ *              currently not used.  The functionality involved the dataspace
+ *              will be implemented in the next version.
+ *
+ * Description:
+ *              This function tests the new API functions added for EED-343:
+ *              H5Dget_num_chunks, H5Dget_chunk_info, and H5Dget_chunk_info_by_coord
+ *              for high bound beyond 1.8.
+ *
+ * Date:        October 2018
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+test_get_chunk_info_110(hid_t fapl)
+{
+    hid_t        chunkfile = -1; /* File ID */
+    char         filename[FILENAME_BUF_SIZE];
+    H5F_libver_t low, high;      /* File format bounds */
+
+    TESTING("getting chunk information in file with versions 1.10");
+    HDprintf("\n"); /* to list sub-tests */
+
+    /* Create the file */
+    h5_fixname(FILENAME[1], fapl, filename, sizeof filename);
+    chunkfile = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    if(chunkfile < 0) TEST_ERROR
+
+    /* Close the file, individual tests will re-open the file with different
+       libvers via the fapl */
+    if(H5Fclose(chunkfile) < 0) TEST_ERROR
+
+    /* Set high bound to the current latest version */
+    high = H5F_LIBVER_LATEST;
+
+    /* Test getting info of chunked datasets in version combo up to 1.10 */
+    for (low = H5F_LIBVER_V110; low <= H5F_LIBVER_LATEST; low++) {
+        /* Set version bounds for creating file */
+        if(H5Pset_libver_bounds(fapl, low, high) < 0)
+            TEST_ERROR
+
+        /* Test getting chunk info when Single Chunk index type is used */
+        if(test_chunk_info_single_chunk(filename, fapl) < 0)
+            TEST_ERROR
+
+        /* Test getting chunk info when Implicit index type is used */
+        if(test_chunk_info_implicit(filename, fapl) < 0)
+            TEST_ERROR
+
+        /* Test getting chunk info when Fixed Array index type is used */
+        if(test_chunk_info_fixed_array(filename, fapl) < 0)
+            TEST_ERROR
+
+        /* Test getting chunk info when Extensible Array index type is used */
+        if(test_chunk_info_extensible_array(filename, fapl) < 0)
+            TEST_ERROR
+
+        /* Test getting chunk info when Version 2 B-trees index type is used */
+        if(test_chunk_info_version2_btrees(filename, fapl) < 0)
+            TEST_ERROR
+    } /* for low libver bound */
+
+    return SUCCEED;
+
+error:
+    H5_FAILED();
+    return FAIL;
+} /* test_get_chunk_info_110() */
+
+/*-------------------------------------------------------------------------
+ * Function:    create_4x4_dset
+ *
+ * Purpose:     Tests functions related to chunk information
+ *
+ * Return:      Success:    SUCCEED
+ *              Failure:    FAIL
+ *
+ * Description:
+ *              The code in this create_4x4_dset function was originally written by
+ *              Pedro in main() that writes a 4x4 dataset by iterating on
+ *              2x2 chunks at a time, with the intention of making a frame
+ *              work to test H5Dget_chunk_info, which was not in the library,
+ *              until now.  For the work in HDFFV-10615, the test function
+ *              test_get_chunk_info was added to test the new query chunk
+ *              API functions: H5Dget_num_chunk, H5Dget_chunk_info, and
+ *              H5Dget_chunk_info_by_coord.  This code can be used at a
+ *              later time, so it is kept here.
+ *              -BMR, November 5, 2018
+ *
+ * Programmer:  Pedro Vicente <pvn@hdfgroup.edu>
+ *              April 7, 2008
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+create_4x4_dset(hid_t fapl)
+{
     hid_t   fid;      /* file ID */
     hid_t   did;      /* dataset ID */
     hid_t   f_sid;    /* file space ID */
@@ -43,19 +1552,21 @@ int main( void )
     int     chunk_data[2][2] = { {1, 1}, {1, 1} };
     int     buf[4][4];
     int     fillvalue = 0;
-    int     i, j, ii, jj;
+    char    filename[FILENAME_BUF_SIZE];
+    hsize_t i, j;
 
     /* create a new file using default properties. */
-    if ((fid = H5Fcreate(H5FILE_NAME, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR;
+    h5_fixname(FILENAME[2], fapl, filename, sizeof filename);
+    if((fid = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+
     /* create the file space */
-    if ((f_sid = H5Screate_simple(RANK, dims, dims)) < 0) TEST_ERROR;
+    if((f_sid = H5Screate_simple(RANK, dims, dims)) < 0) TEST_ERROR
+
     /* create the memory space with chunk dimensions */
-    if ((m_sid = H5Screate_simple(RANK, chunk_dims, chunk_dims)) < 0) TEST_ERROR;
+    if((m_sid = H5Screate_simple(RANK, chunk_dims, chunk_dims)) < 0) TEST_ERROR
     start[0] = 0;
     start[1] = 0;
-    if (H5Sselect_hyperslab(m_sid, H5S_SELECT_SET, start, NULL, chunk_dims, NULL) < 0) TEST_ERROR;
-
-    TESTING("chunk info");
+    if(H5Sselect_hyperslab(m_sid, H5S_SELECT_SET, start, NULL, chunk_dims, NULL) < 0) TEST_ERROR
 
    /*-------------------------------------------------------------------------
     * create a dataset
@@ -63,13 +1574,13 @@ int main( void )
     */
 
     /* modify dataset creation properties, i.e. enable chunking. */
-    if ((pid = H5Pcreate (H5P_DATASET_CREATE)) < 0) TEST_ERROR;
-    if (H5Pset_chunk(pid, RANK, chunk_dims) < 0) TEST_ERROR;
-    if (H5Pset_fill_value(pid, H5T_NATIVE_INT, &fillvalue) < 0) TEST_ERROR;
+    if((pid = H5Pcreate (H5P_DATASET_CREATE)) < 0) TEST_ERROR
+    if(H5Pset_chunk(pid, RANK, chunk_dims) < 0) TEST_ERROR
+    if(H5Pset_fill_value(pid, H5T_NATIVE_INT, &fillvalue) < 0) TEST_ERROR
 
     /* create a new dataset */
-    if((did = H5Dcreate2(fid , DATASETNAME, H5T_NATIVE_INT, f_sid, H5P_DEFAULT, pid, H5P_DEFAULT)) < 0) TEST_ERROR;
-
+    did = H5Dcreate2(fid , DATASETNAME, H5T_NATIVE_INT, f_sid, H5P_DEFAULT, pid, H5P_DEFAULT);
+    if(did < 0) TEST_ERROR
 
    /*-------------------------------------------------------------------------
     * write the dataset in 2x2 chunks
@@ -77,25 +1588,20 @@ int main( void )
     */
 
     /* iterate in dim 0 */
-    for (j = 0; j < chunk_dims[0]; j++)
-    {
-
+    for (j = 0; j < chunk_dims[0]; j++) {
         /* reset start in dim 1 */
         start[1] = 0;
 
         /* iterate in dim 1 */
-        for (i = 0; i < chunk_dims[1]; i++)
-        {
-
+        for (i = 0; i < chunk_dims[1]; i++) {
             /* select file hyperslab to save a 2x2 chunk */
-            if (H5Sselect_hyperslab(f_sid, H5S_SELECT_SET, start, NULL, chunk_dims, NULL) < 0) TEST_ERROR;
+            if(H5Sselect_hyperslab(f_sid, H5S_SELECT_SET, start, NULL, chunk_dims, NULL) < 0) TEST_ERROR
 
             /* write the data to the hyperslab. */
-            if (H5Dwrite(did, H5T_NATIVE_INT, m_sid, f_sid, H5P_DEFAULT, chunk_data) < 0) TEST_ERROR;
+            if(H5Dwrite(did, H5T_NATIVE_INT, m_sid, f_sid, H5P_DEFAULT, chunk_data) < 0) TEST_ERROR
 
             /* read back and display complete dataset 4x4 */
-            if (H5Dread(did, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf) < 0) TEST_ERROR;
-
+            if(H5Dread(did, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf) < 0) TEST_ERROR
 
 #if defined (PRINT_DATA)
             printf("\n");
@@ -105,46 +1611,91 @@ int main( void )
                 printf("\n");
             }
 #endif
-
-
             /* increment start in dim 1 */
             start[1] += 2;
-
-
         }
-
         /* increment start in dim 0 */
         start[0] += 2;
     }
 
-
-
    /*-------------------------------------------------------------------------
     * close
     *-------------------------------------------------------------------------
     */
+    if(H5Dclose(did) < 0) TEST_ERROR
+    if(H5Sclose(f_sid) < 0) TEST_ERROR
+    if(H5Sclose(m_sid) < 0) TEST_ERROR
+    if(H5Pclose(pid) < 0) TEST_ERROR
+    if(H5Fclose(fid) < 0) TEST_ERROR
 
-    if (H5Dclose(did) < 0) TEST_ERROR
-    if (H5Sclose(f_sid) < 0) TEST_ERROR
-    if (H5Sclose(m_sid) < 0) TEST_ERROR
-    if (H5Pclose(pid) < 0) TEST_ERROR
-    if (H5Fclose(fid) < 0) TEST_ERROR
+    return SUCCEED;
 
-    PASSED();
+error:
+    H5Dclose(did);
+    H5Sclose(f_sid);
+    H5Sclose(m_sid);
+    H5Pclose(pid);
+    H5Fclose(fid);
+
+    return FAIL;
+} /* end create_4x4_dset */
 
-    puts("All chunk info tests passed.");
-    return 0;
+/*-------------------------------------------------------------------------
+ * Function:    main
+ *
+ * Purpose:     Tests functions related to chunk information
+ *
+ * Return:      Success:    SUCCEED
+ *              Failure:    FAIL
+ *
+ * Programmer:  Binh-Minh Ribler
+ *              November 5, 2018
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+main(void)
+{
+    hid_t fapl = -1;    /* File access property list */
+    int   nerrors = 0;  /* Number of errors so far */
 
+    h5_reset();
+
+    /* Create a copy of file access property list */
+    if((fapl = H5Pcreate(H5P_FILE_ACCESS)) < 0) TEST_ERROR
+
+    /* Tests getting chunk information of version 1.8 and prior */
+    nerrors += test_get_chunk_info_highest18(fapl) < 0 ? 1 : 0;
+
+    /* Tests getting chunk information of version 1.10 */
+    nerrors += test_get_chunk_info_110(fapl) < 0 ? 1 : 0;
+
+    /* Create a 4x4 dataset (using the existing code to avoid compilation
+       warnings for now) */
+    nerrors += create_4x4_dset(fapl) < 0 ? 1 : 0;
+
+    if(nerrors)
+        goto error;
+
+    HDprintf("All chunk query tests passed.\n");
+
+    h5_cleanup(FILENAME, fapl);
+
+    return SUCCEED;
 
 error:
-    H5Dclose( did );
-    H5Sclose( f_sid );
-    H5Sclose( m_sid );
-    H5Pclose( pid  );
-    H5Fclose( fid );
-    H5_FAILED();
-    return 1;
+    nerrors = MAX(1, nerrors);
+    HDprintf("***** %d QUERY CHUNK INFO TEST%s FAILED! *****\n",
+              nerrors, 1 == nerrors ? "" : "S");
+    return FAIL;
 }
 
+/****************************************************************************
+ Additional tests to be added:
+- create/write to a dataset, do the query before closing the dataset
+- do the query when extending the dataset (shrink or expand)
+- verify that invalid input parameters are handled properly
+- do the query on a non-chunked dataset...
+- test for filter or non-filter
 
-
+****************************************************************************/
diff --git a/test/cork.c b/test/cork.c
index dceaf5a..240be77 100644
--- a/test/cork.c
+++ b/test/cork.c
@@ -286,19 +286,19 @@ static unsigned
 verify_obj_dset_cork(hbool_t swmr)
 {
     /* Variable Declarations */
-    hid_t fid = -1;     /* File ID */
+    hid_t fid = -1;             /* File ID */
     hid_t fapl = -1;            /* File access property list */
     hid_t aid = -1;             /* Attribute ID */
     hid_t sid = -1, sid2 = -1;  /* Dataspace IDs */
     hid_t did = -1, did2 = -1;  /* Dataset IDs */
     hid_t oid = -1;             /* Object ID */
-    hid_t dcpl2;            /* Dataset creation property list */
+    hid_t dcpl2;                /* Dataset creation property list */
     int i = 0;                  /* Local index variable */
-    hsize_t dim[1] = {100}; /* Dataset dimension size */
+    hsize_t dim[1] = {100};     /* Dataset dimension size */
     hsize_t chunk_dim[1] = {7}; /* Dataset chunk dimension size */
     H5O_info_t oinfo, oinfo2;   /* Object metadata information */
     char attrname[500];         /* Name of attribute */
-    unsigned flags;     /* File access flags */
+    unsigned flags;             /* File access flags */
 
     if(swmr) {
         TESTING("cork status for dataset objects with attributes (SWMR)");
@@ -341,7 +341,7 @@ verify_obj_dset_cork(hbool_t swmr)
         TEST_ERROR
 
     /* Attach and write to an attribute to the dataset: DSET */
-    if((aid = H5Acreate2(did, ATTR, H5T_NATIVE_UINT, sid, H5P_DEFAULT, H5P_DEFAULT)) < 0) 
+    if((aid = H5Acreate2(did, ATTR, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT)) < 0) 
         TEST_ERROR
 
     /* Verify cork status of the dataset: DSET */
@@ -380,11 +380,11 @@ verify_obj_dset_cork(hbool_t swmr)
         TEST_ERROR
 
     /* Attach 8 attributes to the dataset */
-    for(i = 0;i < 8; i++) {
-        sprintf(attrname, "attr %d", i);
-        if((aid = H5Acreate2(did2, attrname, H5T_NATIVE_UINT, sid2, H5P_DEFAULT, H5P_DEFAULT)) < 0)
+    for(i = 0; i < 8; i++) {
+        HDsprintf(attrname, "attr %d", i);
+        if((aid = H5Acreate2(did2, attrname, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT)) < 0)
             TEST_ERROR
-        if(H5Awrite(aid, H5T_NATIVE_UINT, &i) < 0)
+        if(H5Awrite(aid, H5T_NATIVE_INT, &i) < 0)
             TEST_ERROR
         if(H5Aclose(aid) < 0)
             TEST_ERROR
diff --git a/test/corrupted_name_len.h5 b/test/corrupted_name_len.h5
new file mode 100644
index 0000000..b5980b7
--- /dev/null
+++ b/test/corrupted_name_len.h5
diff --git a/test/del_many_dense_attrs.c b/test/del_many_dense_attrs.c
new file mode 100644
index 0000000..d88045c
--- /dev/null
+++ b/test/del_many_dense_attrs.c
@@ -0,0 +1,203 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the COPYING file, which can be found at the root of the source code       *
+ * distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.  *
+ * If you do not have access to either file, you may request a copy from     *
+ * help@hdfgroup.org.                                                        *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*
+ * Purpose:	Test to verify that the infinite loop closing library/abort failure
+ *          is fixed when the application creates and removes dense attributes 
+ *          (See HDFFV-10659).
+ */
+
+
+#include "h5test.h"
+
+/* The test file name */
+const char *FILENAME[] = {
+    "del_many_dense_attrs", 
+    NULL
+};
+
+#define ATTR_COUNT  64          /* The number of attributes */
+
+/*-------------------------------------------------------------------------
+ * Function:    catch_signal
+ *
+ * Purpose:     The signal handler to catch the SIGABRT signal.
+ *
+ * Return:      No return
+ *
+ * Programmer:  Vailin Choi
+ *
+ *-------------------------------------------------------------------------
+ */
+static void catch_signal(int H5_ATTR_UNUSED signo)
+{
+    HDexit(1);
+} /* catch_signal() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	main
+ *
+ * Purpose:	Test to verify that the infinite loop closing library/abort failure
+ *          is fixed when the application creates and removes dense attributes 
+ *          (See HDFFV-10659).
+ *
+ * Return:	Success:	exit(EXIT_SUCCESS)
+ *		    Failure:	exit(EXIT_FAILURE)
+ *
+ * Programmer:  Vailin Choi; Dec 2018
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+main(void)
+{
+    hid_t fid = -1;             /* HDF5 File ID                 */
+    hid_t gid = -1;             /* Group ID                     */
+    hid_t sid = -1;             /* Dataspace ID                 */
+    hid_t aid = -1;             /* Attribute ID                 */
+    hid_t tid = -1;             /* Datatype ID                  */
+    hid_t fapl = -1;            /* File access property lists   */
+    hid_t gcpl = -1;            /* Group creation property list */
+    char aname[50];             /* Name of attribute            */
+    char *basename="attr";      /* Name prefix for attribute    */
+    char filename[100];         /* File name                    */
+    int i;                      /* Local index variable         */
+
+    /* Testing setup */
+    h5_reset();
+
+    /* To exit from the file for SIGABRT signal */
+    if(HDsignal(SIGABRT, catch_signal) == SIG_ERR)
+       TEST_ERROR
+
+    fapl = h5_fileaccess();
+    h5_fixname(FILENAME[0], fapl, filename, sizeof(filename));
+
+    /* Set to latest format */
+    if(H5Pset_libver_bounds(fapl, H5F_LIBVER_LATEST, H5F_LIBVER_LATEST) < 0)
+        TEST_ERROR
+
+    /* Create the file  */
+    if((fid = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl)) < 0)
+        TEST_ERROR
+
+    /* Close the file */
+    if(H5Fclose(fid) < 0)
+        TEST_ERROR
+
+     /* Re-open the file */
+    if((fid = H5Fopen(filename, H5F_ACC_RDWR, fapl)) < 0)
+        TEST_ERROR
+
+    /* Create the group creation property list */
+    if((gcpl = H5Pcreate(H5P_GROUP_CREATE)) < 0)
+        TEST_ERROR
+
+    /* Set to use dense storage for all attributes on the group */
+    if(H5Pset_attr_phase_change(gcpl, 0, 0) < 0)
+        TEST_ERROR
+
+    /* Create the group in the file */
+    if((gid = H5Gcreate2(fid, "group", H5P_DEFAULT, gcpl, H5P_DEFAULT)) < 0)
+        TEST_ERROR
+
+    /* Create dataspace */
+    if((sid = H5Screate(H5S_SCALAR)) < 0)
+        TEST_ERROR
+
+    /* Get a copy of the datatype */
+    if((tid = H5Tcopy(H5T_NATIVE_FLOAT)) < 0)
+        TEST_ERROR
+
+    /* Create attributes in the group */
+    for(i = ATTR_COUNT; i >= 0; i--) {
+        /* Set up the attribute name */
+        HDsprintf(aname, "%s%d", basename, i);
+
+        /* Create the attribute */
+        if((aid = H5Acreate2(gid, aname, tid, sid, H5P_DEFAULT, H5P_DEFAULT)) < 0)
+            TEST_ERROR
+
+        /* Write to the attribute */
+        if(H5Awrite(aid, tid, &i) < 0)
+            TEST_ERROR
+
+        /* Close the attribute */
+        if(H5Aclose(aid) < 0)
+            TEST_ERROR
+    }
+    
+    /* Close the datatype */
+    if(H5Tclose(tid) < 0)
+       TEST_ERROR
+
+    /* Close the dataspace */
+    if(H5Sclose(sid) < 0)
+        TEST_ERROR
+
+    /* Close the group */
+    if(H5Gclose(gid) < 0)
+        TEST_ERROR
+
+    /* Close the group creation property list */
+    if(H5Pclose(gcpl) < 0)
+        TEST_ERROR
+
+    /* Close the file */
+    if(H5Fclose(fid) < 0)
+        TEST_ERROR
+
+    /* Re-open the file */
+    if((fid = H5Fopen(filename, H5F_ACC_RDWR, fapl)) < 0)
+        TEST_ERROR
+
+    /* Open the group */
+    if((gid = H5Gopen2(fid, "group", H5P_DEFAULT)) < 0)
+        TEST_ERROR
+
+    /* Delete the attributes */
+    for (i = 0; i <= ATTR_COUNT; i++) {
+        /* Set up the attribute name */
+        HDsprintf(aname, "%s%d", basename, i);
+
+        /* Delete the attribute */
+        if(H5Adelete(gid, aname) < 0)
+            TEST_ERROR
+    } /* end for */
+
+    /* Close the group */
+    if(H5Gclose(gid) < 0)
+        TEST_ERROR
+
+    /* Close the file */
+    if(H5Fclose(fid) < 0)
+        TEST_ERROR
+
+    h5_cleanup(FILENAME, fapl);
+
+    return(EXIT_SUCCESS);
+
+error:
+    H5E_BEGIN_TRY {
+        H5Gclose(gid);
+        H5Sclose(sid);
+        H5Tclose(tid);
+        H5Aclose(aid);
+        H5Fclose(fid);
+        H5Pclose(gcpl);
+        H5Pclose(fapl);
+    } H5E_END_TRY
+
+    return EXIT_FAILURE;
+}
diff --git a/test/direct_chunk.c b/test/direct_chunk.c
index 2ef38ea..1c5862d 100644
--- a/test/direct_chunk.c
+++ b/test/direct_chunk.c
@@ -13,7 +13,7 @@
 
 #include "h5test.h"
 
-#if defined(H5_HAVE_ZLIB_H) && !defined(H5_ZLIB_HEADER) 
+#if defined(H5_HAVE_ZLIB_H) && !defined(H5_ZLIB_HEADER)
 # define H5_ZLIB_HEADER "zlib.h"
 #endif
 #if defined(H5_ZLIB_HEADER)
@@ -46,10 +46,10 @@
 #define DEFLATE_SIZE_ADJUST(s) (HDceil(((double)(s))*H5_DOUBLE(1.001))+H5_DOUBLE(12.0))
 
 /* Temporary filter IDs used for testing */
-#define H5Z_FILTER_BOGUS1	305
-#define H5Z_FILTER_BOGUS2	306
-#define ADD_ON			7
-#define FACTOR			3
+#define H5Z_FILTER_BOGUS1    305
+#define H5Z_FILTER_BOGUS2    306
+#define ADD_ON            7
+#define FACTOR            3
 
 /* Constants for the overwrite test */
 #define OVERWRITE_NDIMS         3
@@ -75,33 +75,33 @@ static size_t filter_bogus2(unsigned int flags, size_t cd_nelmts,
 /* This message derives from H5Z */
 const H5Z_class2_t H5Z_BOGUS1[1] = {{
     H5Z_CLASS_T_VERS,       /* H5Z_class_t version */
-    H5Z_FILTER_BOGUS1,		/* Filter id number		*/
+    H5Z_FILTER_BOGUS1,        /* Filter id number        */
     1, 1,               /* Encoding and decoding enabled */
-    "bogus1",			/* Filter name for debugging	*/
+    "bogus1",            /* Filter name for debugging    */
     NULL,                       /* The "can apply" callback     */
     NULL,                       /* The "set local" callback     */
-    filter_bogus1,		/* The actual filter function	*/
+    filter_bogus1,        /* The actual filter function    */
 }};
 
 const H5Z_class2_t H5Z_BOGUS2[1] = {{
     H5Z_CLASS_T_VERS,       /* H5Z_class_t version */
-    H5Z_FILTER_BOGUS2,		/* Filter id number		*/
+    H5Z_FILTER_BOGUS2,        /* Filter id number        */
     1, 1,               /* Encoding and decoding enabled */
-    "bogus2",			/* Filter name for debugging	*/
+    "bogus2",            /* Filter name for debugging    */
     NULL,                       /* The "can apply" callback     */
     NULL,                       /* The "set local" callback     */
-    filter_bogus2,		/* The actual filter function	*/
+    filter_bogus2,        /* The actual filter function    */
 }};
 
 /*-------------------------------------------------------------------------
- * Function:	test_direct_chunk_write
+ * Function:    test_direct_chunk_write
  *
- * Purpose:	    Test the basic functionality of H5Dwrite_chunk
+ * Purpose:        Test the basic functionality of H5Dwrite_chunk
  *
- * Return:	    Success:	0
- *		        Failure:	1
+ * Return:        Success:    0
+ *                Failure:    1
  *
- * Programmer:  Raymond Lu	
+ * Programmer:  Raymond Lu
  *              30 November 2012
  *
  *-------------------------------------------------------------------------
@@ -113,7 +113,7 @@ test_direct_chunk_write (hid_t file)
     hid_t       dataspace = -1, dataset = -1;
     hid_t       mem_space = -1;
     hid_t       cparms = -1, dxpl = -1;
-    hsize_t     dims[2]  = {NX, NY};        
+    hsize_t     dims[2]  = {NX, NY};
     hsize_t     maxdims[2] = {H5S_UNLIMITED, H5S_UNLIMITED};
     hsize_t     chunk_dims[2] ={CHUNK_NX, CHUNK_NY};
     herr_t      status;
@@ -128,11 +128,11 @@ test_direct_chunk_write (hid_t file)
     size_t      buf_size = CHUNK_NX*CHUNK_NY*sizeof(int);
 
     const Bytef *z_src = (const Bytef*)(direct_buf);
-    Bytef	    *z_dst = NULL;		    /*destination buffer		*/
-    uLongf	     z_dst_nbytes = (uLongf)DEFLATE_SIZE_ADJUST(buf_size);
-    uLong	     z_src_nbytes = (uLong)buf_size;
+    Bytef        *z_dst = NULL;            /*destination buffer        */
+    uLongf         z_dst_nbytes = (uLongf)DEFLATE_SIZE_ADJUST(buf_size);
+    uLong         z_src_nbytes = (uLong)buf_size;
     int          aggression = 9;        /* Compression aggression setting */
-    void	    *outbuf = NULL;         /* Pointer to new buffer */
+    void        *outbuf = NULL;         /* Pointer to new buffer */
 
     hsize_t start[2];  /* Start of hyperslab */
     hsize_t stride[2]; /* Stride of hyperslab */
@@ -167,29 +167,29 @@ test_direct_chunk_write (hid_t file)
      * creation properties.
      */
     if((dataset = H5Dcreate2(file, DATASETNAME1, H5T_NATIVE_INT, dataspace, H5P_DEFAULT,
-			cparms, H5P_DEFAULT)) < 0)
+            cparms, H5P_DEFAULT)) < 0)
         goto error;
 
     /* Initialize the dataset */
     for(i = n = 0; i < NX; i++)
         for(j = 0; j < NY; j++)
-	    data[i][j] = n++;
+        data[i][j] = n++;
 
     if((dxpl = H5Pcreate(H5P_DATASET_XFER)) < 0)
         goto error;
 
     /*
      * Write the data for the dataset.  It should stay in the chunk cache.
-     * It will be evicted from the cache by the H5Dwrite_chunk calls. 
+     * It will be evicted from the cache by the H5Dwrite_chunk calls.
      */
     if((status = H5Dwrite(dataset, H5T_NATIVE_INT, H5S_ALL, H5S_ALL,
-		      dxpl, data)) < 0)
+            dxpl, data)) < 0)
         goto error;
 
     /* Initialize data for one chunk */
     for(i = n = 0; i < CHUNK_NX; i++)
         for(j = 0; j < CHUNK_NY; j++)
-	    direct_buf[i][j] = n++;
+        direct_buf[i][j] = n++;
 
     /* Allocate output (compressed) buffer */
     outbuf = HDmalloc(z_dst_nbytes);
@@ -210,8 +210,8 @@ test_direct_chunk_write (hid_t file)
         goto error;
     }
 
-    /* Write the compressed chunk data repeatedly to cover all the chunks in the 
-     * dataset, using the direct writing function.     */ 
+    /* Write the compressed chunk data repeatedly to cover all the chunks in the
+     * dataset, using the direct writing function.     */
     for(i=0; i<NX/CHUNK_NX; i++) {
         for(j=0; j<NY/CHUNK_NY; j++) {
             status = H5Dwrite_chunk(dataset, dxpl, filter_mask, offset, z_dst_nbytes, outbuf);
@@ -224,7 +224,7 @@ test_direct_chunk_write (hid_t file)
     if(outbuf)
         HDfree(outbuf);
 
-    if(H5Fflush(dataset, H5F_SCOPE_LOCAL) < 0) 
+    if(H5Fflush(dataset, H5F_SCOPE_LOCAL) < 0)
         goto error;
 
     if(H5Dclose(dataset) < 0)
@@ -253,7 +253,7 @@ test_direct_chunk_write (hid_t file)
             if(direct_buf[i][j] != check_chunk[i][j]) {
                 HDprintf("    1. Read different values than written.");
                 HDprintf("    At index %d,%d\n", i, j);
-                HDprintf("    direct_buf=%d, check_chunk=%d\n", direct_buf[i][j], check_chunk[i][j]); 
+                HDprintf("    direct_buf=%d, check_chunk=%d\n", direct_buf[i][j], check_chunk[i][j]);
                 goto error;
             }
         }
@@ -262,7 +262,7 @@ test_direct_chunk_write (hid_t file)
     /* Reinitialize different data for one chunk */
     for(i = 0; i < CHUNK_NX; i++)
         for(j = 0; j < CHUNK_NY; j++)
-	    direct_buf[i][j] = i + j;
+        direct_buf[i][j] = i + j;
 
     /* Allocate output (compressed) buffer */
     outbuf = HDmalloc(z_dst_nbytes);
@@ -283,8 +283,8 @@ test_direct_chunk_write (hid_t file)
         goto error;
     }
 
-    /* Rewrite the compressed chunk data repeatedly to cover all the chunks in the 
-     * dataset, using the direct writing function.     */ 
+    /* Rewrite the compressed chunk data repeatedly to cover all the chunks in the
+     * dataset, using the direct writing function.     */
     offset[0] = offset[1] = 0;
     for(i=0; i<NX/CHUNK_NX; i++) {
         for(j=0; j<NY/CHUNK_NY; j++) {
@@ -298,7 +298,7 @@ test_direct_chunk_write (hid_t file)
     if(outbuf)
         HDfree(outbuf);
 
-    if(H5Fflush(dataset, H5F_SCOPE_LOCAL) < 0) 
+    if(H5Fflush(dataset, H5F_SCOPE_LOCAL) < 0)
         goto error;
 
     if(H5Dclose(dataset) < 0)
@@ -317,7 +317,7 @@ test_direct_chunk_write (hid_t file)
             if(direct_buf[i][j] != check_chunk[i][j]) {
                 HDprintf("    2. Read different values than written.");
                 HDprintf("    At index %d,%d\n", i, j);
-                HDprintf("    direct_buf=%d, check_chunk=%d\n", direct_buf[i][j], check_chunk[i][j]); 
+                HDprintf("    direct_buf=%d, check_chunk=%d\n", direct_buf[i][j], check_chunk[i][j]);
                 goto error;
             }
         }
@@ -331,7 +331,7 @@ test_direct_chunk_write (hid_t file)
     H5Sclose(dataspace);
     H5Pclose(cparms);
     H5Pclose(dxpl);
-    
+
     PASSED();
     return 0;
 
@@ -459,15 +459,15 @@ error:
 } /* end test_direct_chunk_overwrite_data() */
 
 /*-------------------------------------------------------------------------
- * Function:	test_skip_compress_write1
+ * Function:    test_skip_compress_write1
  *
- * Purpose:	Test skipping compression filter when it is the only filter
+ * Purpose:    Test skipping compression filter when it is the only filter
  *              for the dataset
  *
- * Return:	Success:	0
- *		    Failure:	1
+ * Return:    Success:    0
+ *            Failure:    1
  *
- * Programmer:  Raymond Lu	
+ * Programmer:  Raymond Lu
  *              30 November 2012
  *
  *-------------------------------------------------------------------------
@@ -528,7 +528,7 @@ test_skip_compress_write1(hid_t file)
      * creation properties.
      */
     if((dataset = H5Dcreate2(file, DATASETNAME2, H5T_NATIVE_INT, dataspace, H5P_DEFAULT,
-			cparms, H5P_DEFAULT)) < 0)
+            cparms, H5P_DEFAULT)) < 0)
         goto error;
 
     if((dxpl = H5Pcreate(H5P_DATASET_XFER)) < 0)
@@ -636,13 +636,13 @@ error:
 } /* test_skip_compress_write1() */
 
 /*-------------------------------------------------------------------------
- * Function:	filter_bogus1
+ * Function:    filter_bogus1
  *
- * Purpose:	    A bogus filter that adds ADD_ON to the original value
+ * Purpose:        A bogus filter that adds ADD_ON to the original value
  *
- * Return:	    Success:	Data chunk size
+ * Return:        Success:    Data chunk size
  *
- * Programmer:  Raymond Lu	
+ * Programmer:  Raymond Lu
  *              30 November 2012
  *
  *-------------------------------------------------------------------------
@@ -674,13 +674,13 @@ filter_bogus1(unsigned int flags, size_t H5_ATTR_UNUSED cd_nelmts,
 } /* filter_bogus1() */
 
 /*-------------------------------------------------------------------------
- * Function:	filter_bogus2
+ * Function:    filter_bogus2
  *
- * Purpose:	A bogus filter that multiplies the original value by FACTOR.
+ * Purpose:    A bogus filter that multiplies the original value by FACTOR.
  *
- * Return:	Success:	Data chunk size
+ * Return:    Success:    Data chunk size
  *
- * Programmer:  Raymond Lu	
+ * Programmer:  Raymond Lu
  *              30 November 2012
  *-------------------------------------------------------------------------
  */
@@ -711,15 +711,15 @@ filter_bogus2(unsigned int flags, size_t H5_ATTR_UNUSED cd_nelmts,
 } /* filter_bogus2() */
 
 /*-------------------------------------------------------------------------
- * Function:	test_skip_compress_write2
+ * Function:    test_skip_compress_write2
  *
- * Purpose:	Test skipping compression filter when there are three filters
+ * Purpose:    Test skipping compression filter when there are three filters
  *              for the dataset
  *
- * Return:	Success:	0
- *		    Failure:	1
+ * Return:    Success:    0
+ *            Failure:    1
  *
- * Programmer:  Raymond Lu	
+ * Programmer:  Raymond Lu
  *              30 November 2012
  *
  *-------------------------------------------------------------------------
@@ -797,7 +797,7 @@ test_skip_compress_write2(hid_t file)
      * creation properties.
      */
     if((dataset = H5Dcreate2(file, DATASETNAME3, H5T_NATIVE_INT, dataspace, H5P_DEFAULT,
-			cparms, H5P_DEFAULT)) < 0)
+            cparms, H5P_DEFAULT)) < 0)
         goto error;
 
     if((dxpl = H5Pcreate(H5P_DATASET_XFER)) < 0)
@@ -907,14 +907,14 @@ error:
 } /* test_skip_compress_write2() */
 
 /*-------------------------------------------------------------------------
- * Function:	test_data_conv
+ * Function:    test_data_conv
  *
- * Purpose:	Test data conversion
+ * Purpose:    Test data conversion
  *
- * Return:	Success:	0
- *		    Failure:	1
+ * Return:    Success:    0
+ *            Failure:    1
  *
- * Programmer:  Raymond Lu	
+ * Programmer:  Raymond Lu
  *              30 November 2012
  *
  *-------------------------------------------------------------------------
@@ -932,13 +932,13 @@ test_data_conv(hid_t file)
     hid_t       dataspace = -1, dataset = -1;
     hid_t       mem_space = -1;
     hid_t       cparms = -1, dxpl = -1;
-    hsize_t     dims[2]  = {NX, NY};        
+    hsize_t     dims[2]  = {NX, NY};
     hsize_t     maxdims[2] = {H5S_UNLIMITED, H5S_UNLIMITED};
     hsize_t     chunk_dims[2] ={CHUNK_NX, CHUNK_NY};
     herr_t      status;
     int         i, j, n;
-    const hsize_t	four = 4;
-    hid_t	st=-1, dt=-1;
+    const hsize_t    four = 4;
+    hid_t    st=-1, dt=-1;
     hid_t       array_dt;
 
     unsigned    filter_mask = 0;
@@ -1002,7 +1002,7 @@ test_data_conv(hid_t file)
      * creation properties.
      */
     if((dataset = H5Dcreate2(file, DATASETNAME4, st, dataspace, H5P_DEFAULT,
-			cparms, H5P_DEFAULT)) < 0)
+            cparms, H5P_DEFAULT)) < 0)
         goto error;
 
     if((dxpl = H5Pcreate(H5P_DATASET_XFER)) < 0)
@@ -1022,7 +1022,7 @@ test_data_conv(hid_t file)
         }
     }
 
-    /* write the chunk data to dataset, using the direct writing function. 
+    /* write the chunk data to dataset, using the direct writing function.
      * There should be no data conversion involved. */
     offset[0] = CHUNK_NX;
     offset[1] = CHUNK_NY;
@@ -1030,7 +1030,7 @@ test_data_conv(hid_t file)
     if((status = H5Dwrite_chunk(dataset, dxpl, filter_mask, offset, buf_size, direct_buf)) < 0)
         goto error;
 
-    if(H5Fflush(dataset, H5F_SCOPE_LOCAL) < 0) 
+    if(H5Fflush(dataset, H5F_SCOPE_LOCAL) < 0)
         goto error;
 
     if(H5Dclose(dataset) < 0)
@@ -1057,10 +1057,10 @@ test_data_conv(hid_t file)
                     HDprintf("    1. Read different values than written.");
                     HDprintf("    At index %d,%d\n", i, j);
                     HDprintf("    src={a=%d, b=%d, c=[%d,%d,%d,%d], d=%d, e=%d\n",
-                        (direct_buf[i][j]).a, (direct_buf[i][j]).b, (direct_buf[i][j]).c[0], (direct_buf[i][j]).c[1], 
+                        (direct_buf[i][j]).a, (direct_buf[i][j]).b, (direct_buf[i][j]).c[0], (direct_buf[i][j]).c[1],
                         (direct_buf[i][j]).c[2], (direct_buf[i][j]).c[3], (direct_buf[i][j]).d, (direct_buf[i][j]).e);
                     HDprintf("    dst={a=%d, b=%d, c=[%d,%d,%d,%d], d=%d, e=%d\n",
-                        (read_chunk[i][j]).a, (read_chunk[i][j]).b, (read_chunk[i][j]).c[0], (read_chunk[i][j]).c[1], 
+                        (read_chunk[i][j]).a, (read_chunk[i][j]).b, (read_chunk[i][j]).c[0], (read_chunk[i][j]).c[1],
                         (read_chunk[i][j]).c[2], (read_chunk[i][j]).c[3], (read_chunk[i][j]).d, (read_chunk[i][j]).e);
 
                     goto error;
@@ -1094,10 +1094,10 @@ test_data_conv(hid_t file)
                     HDprintf("    1. Read different values than written.");
                     HDprintf("    At index %d,%d\n", i, j);
                     HDprintf("    src={a=%d, b=%d, c=[%d,%d,%d,%d], d=%d, e=%d\n",
-                        (direct_buf[i][j]).a, (direct_buf[i][j]).b, (direct_buf[i][j]).c[0], (direct_buf[i][j]).c[1], 
+                        (direct_buf[i][j]).a, (direct_buf[i][j]).b, (direct_buf[i][j]).c[0], (direct_buf[i][j]).c[1],
                         (direct_buf[i][j]).c[2], (direct_buf[i][j]).c[3], (direct_buf[i][j]).d, (direct_buf[i][j]).e);
                     HDprintf("    dst={a=%d, c=[%d,%d,%d,%d], e=%d\n",
-                        (check_chunk[i][j]).a, (check_chunk[i][j]).c[0], (check_chunk[i][j]).c[1], (check_chunk[i][j]).c[2], 
+                        (check_chunk[i][j]).a, (check_chunk[i][j]).c[0], (check_chunk[i][j]).c[1], (check_chunk[i][j]).c[2],
                         (check_chunk[i][j]).c[3], (check_chunk[i][j]).e);
 
                     goto error;
@@ -1135,14 +1135,14 @@ error:
 } /* test_data_conv() */
 
 /*-------------------------------------------------------------------------
- * Function:	test_invalid_parameters
+ * Function:    test_invalid_parameters
  *
  * Purpose:     Test invalid parameters for H5Dwrite_chunk and H5Dread_chunk
  *
- * Return:      Success:	0
- *              Failure:	1
+ * Return:      Success:    0
+ *              Failure:    1
  *
- * Programmer:  Raymond Lu	
+ * Programmer:  Raymond Lu
  *              30 November 2012
  *
  *-------------------------------------------------------------------------
@@ -1153,7 +1153,7 @@ test_invalid_parameters(hid_t file)
     hid_t       dataspace = -1, dataset = -1;
     hid_t       mem_space = -1;
     hid_t       cparms = -1, dxpl = -1;
-    hsize_t     dims[2]  = {NX, NY};        
+    hsize_t     dims[2]  = {NX, NY};
     hsize_t     chunk_dims[2] ={CHUNK_NX, CHUNK_NY};
     herr_t      status;
     int         i, j, n;
@@ -1187,7 +1187,7 @@ test_invalid_parameters(hid_t file)
      * Create a new contiguous dataset to verify H5Dwrite_chunk/H5Dread_chunk doesn't work
      */
     if((dataset = H5Dcreate2(file, DATASETNAME5, H5T_NATIVE_INT, dataspace, H5P_DEFAULT,
-			cparms, H5P_DEFAULT)) < 0)
+            cparms, H5P_DEFAULT)) < 0)
         goto error;
 
     if((dxpl = H5Pcreate(H5P_DATASET_XFER)) < 0)
@@ -1236,10 +1236,10 @@ test_invalid_parameters(hid_t file)
      * creation properties.
      */
     if((dataset = H5Dcreate2(file, DATASETNAME6, H5T_NATIVE_INT, dataspace, H5P_DEFAULT,
-			cparms, H5P_DEFAULT)) < 0)
+            cparms, H5P_DEFAULT)) < 0)
         goto error;
 
-    /* Check invalid dataset ID for H5Dwrite_chunk and H5Dread_chunk */ 
+    /* Check invalid dataset ID for H5Dwrite_chunk and H5Dread_chunk */
     H5E_BEGIN_TRY {
         if((status = H5Dwrite_chunk((hid_t)-1, dxpl, filter_mask, offset, buf_size, direct_buf)) != FAIL)
             goto error;
@@ -1301,7 +1301,7 @@ test_invalid_parameters(hid_t file)
     /* Check invalid buffer size for H5Dwrite_chunk only */
     offset[0] = CHUNK_NX;
     offset[1] = CHUNK_NY;
-    buf_size = 0; 
+    buf_size = 0;
     H5E_BEGIN_TRY {
         if((status = H5Dwrite_chunk(dataset, dxpl, filter_mask, offset, buf_size, direct_buf)) != FAIL)
             goto error;
@@ -1329,7 +1329,7 @@ test_invalid_parameters(hid_t file)
     H5Sclose(dataspace);
     H5Pclose(cparms);
     H5Pclose(dxpl);
-    
+
     PASSED();
     return 0;
 
@@ -1635,7 +1635,7 @@ test_direct_chunk_read_cache (hid_t file, hbool_t flush)
                 goto error;
             if(read_buf_size == 0)
                 goto error;
-        
+
             /* Read the compressed chunk back using the direct read function. */
             if((status = H5Dread_chunk(dataset, dxpl, offset, &filter_mask, outbuf)) < 0)
                 goto error;
@@ -1910,10 +1910,10 @@ test_read_unallocated_chunk (hid_t file)
         goto error;
 
     /* Write a single chunk to intialize the chunk storage */
-    HDmemset(&chunk_dims, 0, sizeof(chunk_dims));
+    HDmemset(direct_buf, 0, CHUNK_NX * CHUNK_NY * sizeof(int));
     offset[0] = 0; offset[1] = 0;
 
-    if(H5Dwrite_chunk(dataset, dxpl, filter_mask, offset, chunk_nbytes, &chunk_dims) < 0)
+    if(H5Dwrite_chunk(dataset, dxpl, filter_mask, offset, chunk_nbytes, direct_buf) < 0)
         goto error;
 
     /* Attempt to read each chunk in the dataset. Chunks are not allocated,
@@ -1986,7 +1986,7 @@ error:
  *              this jira issue:
  *                  Create a file with the latest format and a chunked dataset
  *                  with one single chunk.  The library will use single chunk
- *                  index for the dataset.  
+ *                  index for the dataset.
  *                  Verify that the data read is the same as the written data.
  *
  * Return:      Success:        0
@@ -2106,15 +2106,15 @@ error:
 } /* test_single_chunk_latest() */
 
 /*-------------------------------------------------------------------------
- * Function:	Main function
+ * Function:    Main function
  *
- * Purpose:	    Test direct chunk write function H5Dwrite_chunk and
+ * Purpose:        Test direct chunk write function H5Dwrite_chunk and
  *              chunk direct read function H5Dread_chunk
  *
- * Return:	    Success:	0
- *		        Failure:	1
+ * Return:        Success:    0
+ *                Failure:    1
  *
- * Programmer:  Raymond Lu	
+ * Programmer:  Raymond Lu
  *              30 November 2012
  *
  *-------------------------------------------------------------------------
@@ -2134,7 +2134,7 @@ int main( void )
 #ifdef H5_HAVE_FILTER_DEFLATE
     nerrors += test_direct_chunk_write(file_id);
 #endif /* H5_HAVE_FILTER_DEFLATE */
-	nerrors += test_direct_chunk_overwrite_data(file_id);
+    nerrors += test_direct_chunk_overwrite_data(file_id);
     nerrors += test_skip_compress_write1(file_id);
     nerrors += test_skip_compress_write2(file_id);
     nerrors += test_data_conv(file_id);
diff --git a/test/dsets.c b/test/dsets.c
index d23f438..9562ec9 100644
--- a/test/dsets.c
+++ b/test/dsets.c
@@ -87,6 +87,8 @@ const char *FILENAME[] = {
     NULL
 };
 
+#define OHMIN_FILENAME_A "ohdr_min_a"
+
 #define FILENAME_BUF_SIZE       1024
 #define KB                      1024
 
@@ -268,6 +270,13 @@ const char *FILENAME[] = {
 #define STORAGE_SIZE_CHUNK_DIM1 5
 #define STORAGE_SIZE_CHUNK_DIM2 5
 
+/* Parameters for testing version bounds */
+#define VDS_FNAME1  "virtual_file1"
+#define VDS_FNAME2  "virtual_file2"
+#define SRC_FNAME   "source_file"
+#define SRC_DSET    "src_dset"
+#define V_DSET      "v_dset"
+
 /* Shared global arrays */
 #define DSET_DIM1       100
 #define DSET_DIM2       200
@@ -339,7 +348,7 @@ filter_count(unsigned int flags, size_t H5_ATTR_UNUSED cd_nelmts,
         count_nbytes_written += nbytes;
 
     return nbytes;
-}
+} /* end filter_count() */
 
 
 /*-------------------------------------------------------------------------
@@ -486,7 +495,7 @@ test_create(hid_t file)
 
  error:
     return -1;
-}
+} /* end test_create() */
 
 
 /*-------------------------------------------------------------------------
@@ -622,7 +631,7 @@ error:
     if(tconv_buf)
         HDfree(tconv_buf);
     return -1;
-}
+} /* end test_simple_io() */
 
 
 /*-------------------------------------------------------------------------
@@ -728,7 +737,7 @@ error:
     if(f > 0)
         HDclose(f);
     return -1;
-}
+} /* end test_userblock_offset() */
 
 
 /*-------------------------------------------------------------------------
@@ -921,7 +930,7 @@ test_compact_io(hid_t fapl)
     } H5E_END_TRY;
 
     return -1;
-}
+} /* end test_compact_io() */
 
 
 /*-------------------------------------------------------------------------
@@ -1336,7 +1345,7 @@ test_conv_buffer(hid_t fid)
 
 error:
   return -1;
-}
+} /* end test_conv_buffer() */
 
 
 /*-------------------------------------------------------------------------
@@ -1420,7 +1429,7 @@ error:
     } H5E_END_TRY;
 
     return -1;
-}
+} /* end test_tconv() */
 
 /* This message derives from H5Z */
 const H5Z_class2_t H5Z_BOGUS[1] = {{
@@ -1453,7 +1462,7 @@ can_apply_bogus(hid_t H5_ATTR_UNUSED dcpl_id, hid_t type_id, hid_t H5_ATTR_UNUSE
         return 1;
     else
         return -1;
-}
+} /* end can_apply_bogus() */
 
 
 /*-------------------------------------------------------------------------
@@ -1471,7 +1480,7 @@ filter_bogus(unsigned int H5_ATTR_UNUSED flags, size_t H5_ATTR_UNUSED cd_nelmts,
       size_t H5_ATTR_UNUSED *buf_size, void H5_ATTR_UNUSED **buf)
 {
     return nbytes;
-}
+} /* end filter_bogus() */
 
 
 /*-------------------------------------------------------------------------
@@ -1571,7 +1580,7 @@ filter_bogus2(unsigned int flags, size_t cd_nelmts,
     /* Filter is "no op" */
     else
         return(nbytes);
-}
+} /* end filter_bogus2() */
 
 
 /*-------------------------------------------------------------------------
@@ -1589,7 +1598,7 @@ filter_bogus3(unsigned int H5_ATTR_UNUSED flags, size_t H5_ATTR_UNUSED cd_nelmts
       size_t H5_ATTR_UNUSED *buf_size, void H5_ATTR_UNUSED **buf)
 {
     return 0;
-}
+} /* end filter_bogus3() */
 
 /* This message derives from H5Z */
 const H5Z_class2_t H5Z_CORRUPT[1] = {{
@@ -1678,7 +1687,7 @@ filter_cb_cont(H5Z_filter_t filter, void H5_ATTR_UNUSED *buf, size_t H5_ATTR_UNU
        return H5Z_CB_CONT;
     else
         return H5Z_CB_FAIL;
-}
+} /* end filter_cb_cont() */
 
 
 /*-------------------------------------------------------------------------
@@ -1697,7 +1706,7 @@ filter_cb_fail(H5Z_filter_t filter, void H5_ATTR_UNUSED *buf, size_t H5_ATTR_UNU
        return H5Z_CB_FAIL;
     else
        return H5Z_CB_CONT;
-}
+} /* end filter_cb_fail() */
 
 
 /*-------------------------------------------------------------------------
@@ -2046,7 +2055,7 @@ error:
     if(tconv_buf)
         HDfree (tconv_buf);
     return -1;
-}
+} /* end test_filter_internal() */
 
 /*-------------------------------------------------------------------------
  * Function:  test_filter_noencoder
@@ -2164,7 +2173,7 @@ error:
         H5Fclose(file_id);
 
     return -1;
-}
+} /* end test_filter_noencoder() */
 #endif /* H5_HAVE_FILTER_SZIP */
 
 /*-------------------------------------------------------------------------
@@ -2234,7 +2243,7 @@ test_get_filter_info(void)
 
 error:
   return -1;
-}
+} /* end test_get_filter_info() */
 
 /*-------------------------------------------------------------------------
  * Function:  test_filters
@@ -2509,7 +2518,7 @@ H5_ATTR_UNUSED
 
 error:
     return -1;
-}
+} /* end test_filters() */
 
 
 /*-------------------------------------------------------------------------
@@ -2849,7 +2858,7 @@ test_onebyte_shuffle(hid_t file)
 
 error:
     return -1;
-}
+} /* end test_onebyte_shuffle() */
 
 
 /*-------------------------------------------------------------------------
@@ -2967,7 +2976,7 @@ test_nbit_int(hid_t file)
 
 error:
     return -1;
-}
+} /* end test_nbit_int() */
 
 
 /*-------------------------------------------------------------------------
@@ -3085,7 +3094,7 @@ test_nbit_float(hid_t file)
 
 error:
     return -1;
-}
+} /* end test_nbit_float() */
 
 
 /*-------------------------------------------------------------------------
@@ -3217,7 +3226,7 @@ test_nbit_double(hid_t file)
 
 error:
     return -1;
-}
+} /* end test_nbit_double() */
 
 
 /*-------------------------------------------------------------------------
@@ -3344,7 +3353,7 @@ test_nbit_array(hid_t file)
 
 error:
     return -1;
-}
+} /* end test_nbit_array() */
 
 
 /*-------------------------------------------------------------------------
@@ -3561,7 +3570,7 @@ test_nbit_compound(hid_t file)
 
 error:
     return -1;
-}
+} /* end test_nbit_compound() */
 
 
 /*-------------------------------------------------------------------------
@@ -3906,7 +3915,7 @@ out:
 
 error:
     return -1;
-}
+} /* end test_nbit_compound_2() */
 
 
 /*-------------------------------------------------------------------------
@@ -4086,7 +4095,7 @@ test_nbit_compound_3(hid_t file)
 
 error:
     return -1;
-}
+} /* end test_nbit_compound_3() */
 
 
 /*-------------------------------------------------------------------------
@@ -4253,7 +4262,7 @@ test_nbit_int_size(hid_t file)
    return 0;
 error:
     return -1;
-}
+} /* end test_nbit_int_size() */
 
 
 /*-------------------------------------------------------------------------
@@ -4450,7 +4459,7 @@ test_nbit_flt_size(hid_t file)
    return 0;
 error:
     return -1;
-}
+} /* end test_nbit_flt_size() */
 
 /*-------------------------------------------------------------------------
  * Function:    test_scaleoffset_int
@@ -4561,7 +4570,7 @@ test_scaleoffset_int(hid_t file)
     return 0;
 error:
     return -1;
-}
+} /* end test_scaleoffset_int() */
 
 
 /*-------------------------------------------------------------------------
@@ -4689,7 +4698,7 @@ test_scaleoffset_int_2(hid_t file)
     return 0;
 error:
     return -1;
-}
+} /* end test_scaleoffset_int_2() */
 
 
 /*-------------------------------------------------------------------------
@@ -4802,7 +4811,7 @@ test_scaleoffset_float(hid_t file)
     return 0;
 error:
     return -1;
-}
+} /* end test_scaleoffset_float() */
 
 
 /*-------------------------------------------------------------------------
@@ -4931,7 +4940,7 @@ test_scaleoffset_float_2(hid_t file)
     return 0;
 error:
     return -1;
-}
+} /* end test_scaleoffset_float_2() */
 
 
 /*-------------------------------------------------------------------------
@@ -5044,7 +5053,7 @@ test_scaleoffset_double(hid_t file)
     return 0;
 error:
     return -1;
-}
+} /* end test_scaleoffset_double() */
 
 
 /*-------------------------------------------------------------------------
@@ -5174,7 +5183,7 @@ test_scaleoffset_double_2(hid_t file)
     return 0;
 error:
     return -1;
-}
+} /* end test_scaleoffset_double_2() */
 
 
 /*-------------------------------------------------------------------------
@@ -5241,7 +5250,7 @@ test_multiopen (hid_t file)
     H5Pclose(dcpl);
     } H5E_END_TRY;
     return -1;
-}
+} /* end test_multiopen () */
 
 
 /*-------------------------------------------------------------------------
@@ -5337,7 +5346,7 @@ test_types(hid_t file)
     H5Dclose(dset);
     } H5E_END_TRY;
     return -1;
-}
+} /* end test_types() */
 
 /* This message derives from H5Z */
 const H5Z_class2_t H5Z_CAN_APPLY_TEST[1] = {{
@@ -6576,7 +6585,7 @@ error:
             HDfree(buf);
     } H5E_END_TRY;
     return -1;
-}
+} /* end auxread_fdata() */
 
 
 /*-------------------------------------------------------------------------
@@ -10027,7 +10036,7 @@ error:
     H5Fclose(fid);
     } H5E_END_TRY;
     return -1;
-} /* test_idx_compatible */
+} /* end test_idx_compatible() */
 
 /*-------------------------------------------------------------------------
  *
@@ -10167,7 +10176,7 @@ error:
         H5Fclose(fid);
     } H5E_END_TRY;
     return -1;
-} /* test_unfiltered_edge_chunks */
+} /* end test_unfiltered_edge_chunks() */
 
 
 /*-------------------------------------------------------------------------
@@ -10864,7 +10873,7 @@ error:
         H5Sclose(msid);
     } H5E_END_TRY;
     return -1;
-} /* test_farray_hdr_fd() */
+} /* end test_farray_hdr_fd() */
 
 
 /*-------------------------------------------------------------------------
@@ -10984,7 +10993,7 @@ error:
         H5Sclose(msid);
     } H5E_END_TRY;
     return -1;
-} /* test_bt2_hdr_fd() */
+} /* end test_bt2_hdr_fd() */
 
 
 /*-------------------------------------------------------------------------
@@ -12182,7 +12191,7 @@ scatter_error_cb_fail(void **src_buf/*out*/, size_t *src_buf_bytes_used/*out*/,
     *src_buf_bytes_used = nelmts * sizeof(scatter_info->src_buf[0]);
 
     return FAIL;
-}
+} /* end scatter_error_cb_fail() */
 
 static herr_t
 scatter_error_cb_null(void **src_buf/*out*/, size_t *src_buf_bytes_used/*out*/,
@@ -12200,7 +12209,7 @@ scatter_error_cb_null(void **src_buf/*out*/, size_t *src_buf_bytes_used/*out*/,
     *src_buf_bytes_used = nelmts * sizeof(scatter_info->src_buf[0]);
 
     return SUCCEED;
-}
+} /* end scatter_error_cb_null() */
 
 static herr_t
 scatter_error_cb_unalign(void **src_buf/*out*/, size_t *src_buf_bytes_used/*out*/,
@@ -12211,7 +12220,7 @@ scatter_error_cb_unalign(void **src_buf/*out*/, size_t *src_buf_bytes_used/*out*
     *src_buf_bytes_used = *(size_t *)_src_buf_bytes_used;
 
     return SUCCEED;
-}
+} /* end scatter_error_cb_unalign() */
 
 static herr_t
 test_scatter_error(void)
@@ -12374,7 +12383,7 @@ gather_error_cb_fail(const void H5_ATTR_UNUSED *dst_buf,
     size_t H5_ATTR_UNUSED dst_buf_bytes_used, void H5_ATTR_UNUSED *op_data)
 {
     return FAIL;
-}
+} /* end gather_error_cb_fail() */
 
 static herr_t
 test_gather_error(void)
@@ -12587,7 +12596,8 @@ static herr_t dls_01_read_stuff( hid_t fid );
 static herr_t dls_01_main( void );
 
 static herr_t
-dls_01_setup_file( hid_t fid ) {
+dls_01_setup_file( hid_t fid )
+{
 
     int status = 0;
     hid_t sid = 0, did = 0, tid = 0, dcpl = 0;
@@ -12632,10 +12642,11 @@ error:
 
     return -1;
 
-} /* dls_01_setup_file */
+} /* end dls_01_setup_file() */
 
 static herr_t
-dls_01_write_data( hid_t fid, char* buffer ) {
+dls_01_write_data( hid_t fid, char* buffer )
+{
 
     int status = 0;
     hid_t did = 0, tid = 0;
@@ -12668,10 +12679,11 @@ error:
 
     return -1;
 
-} /* dls_01_write_data */
+} /* end dls_01_write_data() */
 
 static herr_t
-dls_01_read_stuff( hid_t fid ) {
+dls_01_read_stuff( hid_t fid )
+{
 
     int status = 0;
     hid_t did = 0;
@@ -12692,10 +12704,11 @@ error:
 
     return -1;
 
-} /* dls_01_read_stuff() */
+} /* end dls_01_read_stuff() */
 
 static herr_t
-dls_01_main( void ) {
+dls_01_main( void )
+{
 
     char filename[512];
     int status = 0;
@@ -12761,7 +12774,7 @@ error:
 
     return -1;
 
-} /* dls_01_main() */
+} /* end dls_01_main() */
 
 /*-------------------------------------------------------------------------
  * Function:    test_compact_open_close_dirty
@@ -12879,7 +12892,7 @@ error:
         H5Fclose(fid);
     } H5E_END_TRY;
     return -1;
-} /* test_compact_open_close_dirty() */
+} /* end test_compact_open_close_dirty() */
 
 
 /*-------------------------------------------------------------------------
@@ -12888,8 +12901,8 @@ error:
  * Purpose:     Tests various format versions.
  *              (Currently, only virtual dataset feature)
  *
- * Return:      Success:    0
- *              Failure:    -1
+ * Return:      Success:    SUCCEED
+ *              Failure:    FAIL
  * Description:
  *              This function attempts to create a virtual dataset in all
  *              valid combinations of low/high library format bounds.  Creation
@@ -12898,13 +12911,8 @@ error:
  *
  *-------------------------------------------------------------------------
  */
-#define VDS_FNAME1  "virtual_file1"
-#define VDS_FNAME2  "virtual_file2"
-#define SRC_FNAME   "source_file"
-#define SRC_DSET    "src_dset"
-#define V_DSET      "v_dset"
 static herr_t
-test_versionbounds()
+test_versionbounds(void)
 {
     hid_t fapl = -1;
     hid_t srcfile = -1;   /* Files with source dsets */
@@ -13018,7 +13026,7 @@ test_versionbounds()
         TEST_ERROR
     dcpl = -1;
     PASSED();
-    return 0;
+    return SUCCEED;
 
  error:
     H5E_BEGIN_TRY {
@@ -13031,8 +13039,126 @@ test_versionbounds()
         H5Fclose(srcfile);
         H5Fclose(vfile);
     } H5E_END_TRY;
-    return -1;
-} /* test_versionbounds() */
+    return FAIL;
+} /* end test_versionbounds() */
+
+
+/*-----------------------------------------------------------------------------
+ * Function:   test_object_header_minimization_dcpl
+ *
+ * Purpose:    Test the "datset object header minimization" property as part of
+ *             the DCPL.
+ *
+ * Return:     Success/pass:   0
+ *             Failure/error: -1
+ *
+ * Programmer: Jacob Smith
+ *             2018 August 15
+ *
+ * Changes:    None.
+ *-----------------------------------------------------------------------------
+ */
+static herr_t
+test_object_header_minimization_dcpl(hid_t fapl_id)
+{
+    hid_t    dcpl_id  = -1;
+    hid_t    file_id  = -1;
+    char     filename[FILENAME_BUF_SIZE] = "";
+    hbool_t  minimize = FALSE;
+    herr_t   ret;
+
+    TESTING("dcpl flags to minimize dataset object header");
+
+    /*********/
+    /* SETUP */
+    /*********/
+
+    if(NULL == h5_fixname(OHMIN_FILENAME_A, fapl_id, filename, sizeof(filename)))
+        TEST_ERROR
+
+    file_id = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl_id);
+    if (file_id == H5I_INVALID_HID)
+        TEST_ERROR
+
+    dcpl_id = H5Pcreate(H5P_DATASET_CREATE);
+    if (dcpl_id == H5I_INVALID_HID)
+        TEST_ERROR
+
+    /*********/
+    /* TESTS */
+    /*********/
+
+    /* default value (not set explicitly)
+     */
+    if (H5Pget_dset_no_attrs_hint(dcpl_id, &minimize) == FAIL)
+        TEST_ERROR
+    if (FALSE != minimize)
+        TEST_ERROR
+
+    /* FALSE-set value
+     */
+    if (H5Pset_dset_no_attrs_hint(dcpl_id, FALSE) == FAIL)
+        TEST_ERROR
+    if (H5Pget_dset_no_attrs_hint(dcpl_id, &minimize) == FAIL)
+        TEST_ERROR
+    if (FALSE != minimize)
+        TEST_ERROR
+
+    /* TRUE-set value
+     */
+    if (H5Pset_dset_no_attrs_hint(dcpl_id, TRUE) == FAIL)
+        TEST_ERROR
+    if (H5Pget_dset_no_attrs_hint(dcpl_id, &minimize) == FAIL)
+        TEST_ERROR
+    if (TRUE != minimize)
+        TEST_ERROR
+
+    /* error cases
+     */
+    H5E_BEGIN_TRY {
+        ret = H5Pget_dset_no_attrs_hint(-1, &minimize);
+    } H5E_END_TRY;
+    if (ret == SUCCEED)
+        TEST_ERROR
+
+    H5E_BEGIN_TRY {
+        ret = H5Pset_dset_no_attrs_hint(-1, FALSE);
+    } H5E_END_TRY;
+    if (ret == SUCCEED)
+        TEST_ERROR
+
+    H5E_BEGIN_TRY {
+        ret = H5Pset_dset_no_attrs_hint(-1, TRUE);
+    } H5E_END_TRY;
+    if (ret == SUCCEED)
+        TEST_ERROR
+
+    H5E_BEGIN_TRY {
+        ret = H5Pget_dset_no_attrs_hint(dcpl_id, NULL);
+    } H5E_END_TRY;
+    if (ret == SUCCEED)
+        TEST_ERROR
+
+    /************/
+    /* TEARDOWN */
+    /************/
+
+    if (H5Fclose(file_id) == FAIL)
+        TEST_ERROR
+
+    if (H5Pclose(dcpl_id) == FAIL)
+        TEST_ERROR
+
+    PASSED();
+    return SUCCEED;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Pclose(dcpl_id);
+        H5Fclose(file_id);
+    } H5E_END_TRY;
+    return FAIL;
+} /* end test_object_header_minimization_dcpl() */
 
 
 /*-------------------------------------------------------------------------
@@ -13056,6 +13182,7 @@ main(void)
     hid_t    fcpl = -1, fcpl2 = -1;
     unsigned new_format;
     unsigned paged;
+    unsigned minimized_ohdr;
     int      mdc_nelmts;
     size_t   rdcc_nelmts;
     size_t   rdcc_nbytes;
@@ -13111,113 +13238,122 @@ main(void)
         if(!contig_addr_vfd && paged)
             continue;
 
-        /* Test with old & new format groups */
-        for(new_format = FALSE; new_format <= TRUE; new_format++) {
-            hid_t my_fapl, my_fcpl;
-
-            /* Set the FAPL for the type of format */
-            if(new_format) {
-                my_fapl = fapl2;
-                if(paged) {
-                    my_fcpl = fcpl2;
-                    puts("\nTesting with new file format and paged aggregation");
-                } else {
-                    my_fcpl = fcpl;
-                    puts("\nTesting with new file format and non-paged aggregation");
-                }
-            } /* end if */
-            else {
-                my_fapl = fapl;
-                if(paged) {
-                    my_fcpl = fcpl2;
-                    puts("Testing with old file format and paged aggregation:");
-                } else {
-                    my_fcpl = fcpl;
-                    puts("Testing with old file format and non-paged aggregation:");
-                }
-            } /* end else */
+        for(minimized_ohdr = FALSE; minimized_ohdr <= TRUE; minimized_ohdr++) {
+
+            /* Test with old & new format groups */
+            for(new_format = FALSE; new_format <= TRUE; new_format++) {
+                hid_t my_fapl, my_fcpl;
+
+                /* Set the FAPL for the type of format */
+                if(new_format) {
+                    my_fapl = fapl2;
+                    if(paged) {
+                        my_fcpl = fcpl2;
+                        puts("\nTesting with new file format and paged aggregation");
+                    } else {
+                        my_fcpl = fcpl;
+                        puts("\nTesting with new file format and non-paged aggregation");
+                    }
+                } /* end if */
+                else {
+                    my_fapl = fapl;
+                    if(paged) {
+                        my_fcpl = fcpl2;
+                        puts("Testing with old file format and paged aggregation:");
+                    } else {
+                        my_fcpl = fcpl;
+                        puts("Testing with old file format and non-paged aggregation:");
+                    }
+                } /* end else */
 
-            /* Create the file for this test */
-            if((file = H5Fcreate(filename, H5F_ACC_TRUNC, my_fcpl, my_fapl)) < 0)
-                goto error;
+                /* Create the file for this test */
+                if((file = H5Fcreate(filename, H5F_ACC_TRUNC, my_fcpl, my_fapl)) < 0)
+                    goto error;
 
-            /* Cause the library to emit initial messages */
-            if((grp = H5Gcreate2(file, "emit diagnostics", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0)
-                goto error;
-            if(H5Oset_comment(grp, "Causes diagnostic messages to be emitted") < 0)
-                goto error;
-            if(H5Gclose(grp) < 0)
-                goto error;
+                if (TRUE == minimized_ohdr) {
+                    if (0 > H5Fset_dset_no_attrs_hint(file, TRUE))
+                        goto error;
+                    puts("(minimized dataset object headers with file setting)");
+                }
 
-            nerrors += (test_create(file) < 0             ? 1 : 0);
-            nerrors += (test_simple_io(envval, my_fapl) < 0        ? 1 : 0);
-            nerrors += (test_compact_io(my_fapl) < 0          ? 1 : 0);
-            nerrors += (test_max_compact(my_fapl) < 0        ? 1 : 0);
-            nerrors += (test_compact_open_close_dirty(my_fapl) < 0     ? 1 : 0);
-            nerrors += (test_conv_buffer(file) < 0            ? 1 : 0);
-            nerrors += (test_tconv(file) < 0            ? 1 : 0);
-            nerrors += (test_filters(file, my_fapl) < 0        ? 1 : 0);
-            nerrors += (test_onebyte_shuffle(file) < 0         ? 1 : 0);
-            nerrors += (test_nbit_int(file) < 0                 ? 1 : 0);
-            nerrors += (test_nbit_float(file) < 0                     ? 1 : 0);
-            nerrors += (test_nbit_double(file) < 0                     ? 1 : 0);
-            nerrors += (test_nbit_array(file) < 0                 ? 1 : 0);
-            nerrors += (test_nbit_compound(file) < 0         ? 1 : 0);
-            nerrors += (test_nbit_compound_2(file) < 0         ? 1 : 0);
-            nerrors += (test_nbit_compound_3(file) < 0         ? 1 : 0);
-            nerrors += (test_nbit_int_size(file) < 0         ? 1 : 0);
-            nerrors += (test_nbit_flt_size(file) < 0         ? 1 : 0);
-            nerrors += (test_scaleoffset_int(file) < 0         ? 1 : 0);
-            nerrors += (test_scaleoffset_int_2(file) < 0             ? 1 : 0);
-            nerrors += (test_scaleoffset_float(file) < 0             ? 1 : 0);
-            nerrors += (test_scaleoffset_float_2(file) < 0             ? 1 : 0);
-            nerrors += (test_scaleoffset_double(file) < 0             ? 1 : 0);
-            nerrors += (test_scaleoffset_double_2(file) < 0     ? 1 : 0);
-            nerrors += (test_multiopen (file) < 0                ? 1 : 0);
-            nerrors += (test_types(file) < 0                       ? 1 : 0);
-            nerrors += (test_userblock_offset(envval, my_fapl, new_format) < 0  ? 1 : 0);
-            nerrors += (test_missing_filter(file) < 0        ? 1 : 0);
-            nerrors += (test_can_apply(file) < 0                ? 1 : 0);
-            nerrors += (test_can_apply2(file) < 0                ? 1 : 0);
-            nerrors += (test_set_local(my_fapl) < 0                ? 1 : 0);
-            nerrors += (test_can_apply_szip(file) < 0        ? 1 : 0);
-            nerrors += (test_compare_dcpl(file) < 0                ? 1 : 0);
-            nerrors += (test_copy_dcpl(file, my_fapl) < 0            ? 1 : 0);
-            nerrors += (test_filter_delete(file) < 0        ? 1 : 0);
-            nerrors += (test_filters_endianess() < 0            ? 1 : 0);
-            nerrors += (test_zero_dims(file) < 0                ? 1 : 0);
-            nerrors += (test_missing_chunk(file) < 0        ? 1 : 0);
-            nerrors += (test_random_chunks(my_fapl) < 0        ? 1 : 0);
+                /* Cause the library to emit initial messages */
+                if((grp = H5Gcreate2(file, "emit diagnostics", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0)
+                    goto error;
+                if(H5Oset_comment(grp, "Causes diagnostic messages to be emitted") < 0)
+                    goto error;
+                if(H5Gclose(grp) < 0)
+                    goto error;
+
+                nerrors += (test_create(file) < 0             ? 1 : 0);
+                nerrors += (test_simple_io(envval, my_fapl) < 0        ? 1 : 0);
+                nerrors += (test_compact_io(my_fapl) < 0          ? 1 : 0);
+                nerrors += (test_max_compact(my_fapl) < 0        ? 1 : 0);
+                nerrors += (test_compact_open_close_dirty(my_fapl) < 0     ? 1 : 0);
+                nerrors += (test_conv_buffer(file) < 0            ? 1 : 0);
+                nerrors += (test_tconv(file) < 0            ? 1 : 0);
+                nerrors += (test_filters(file, my_fapl) < 0        ? 1 : 0);
+                nerrors += (test_onebyte_shuffle(file) < 0         ? 1 : 0);
+                nerrors += (test_nbit_int(file) < 0                 ? 1 : 0);
+                nerrors += (test_nbit_float(file) < 0                     ? 1 : 0);
+                nerrors += (test_nbit_double(file) < 0                     ? 1 : 0);
+                nerrors += (test_nbit_array(file) < 0                 ? 1 : 0);
+                nerrors += (test_nbit_compound(file) < 0         ? 1 : 0);
+                nerrors += (test_nbit_compound_2(file) < 0         ? 1 : 0);
+                nerrors += (test_nbit_compound_3(file) < 0         ? 1 : 0);
+                nerrors += (test_nbit_int_size(file) < 0         ? 1 : 0);
+                nerrors += (test_nbit_flt_size(file) < 0         ? 1 : 0);
+                nerrors += (test_scaleoffset_int(file) < 0         ? 1 : 0);
+                nerrors += (test_scaleoffset_int_2(file) < 0             ? 1 : 0);
+                nerrors += (test_scaleoffset_float(file) < 0             ? 1 : 0);
+                nerrors += (test_scaleoffset_float_2(file) < 0             ? 1 : 0);
+                nerrors += (test_scaleoffset_double(file) < 0             ? 1 : 0);
+                nerrors += (test_scaleoffset_double_2(file) < 0     ? 1 : 0);
+                nerrors += (test_multiopen (file) < 0                ? 1 : 0);
+                nerrors += (test_types(file) < 0                       ? 1 : 0);
+                nerrors += (test_userblock_offset(envval, my_fapl, new_format) < 0  ? 1 : 0);
+                nerrors += (test_missing_filter(file) < 0        ? 1 : 0);
+                nerrors += (test_can_apply(file) < 0                ? 1 : 0);
+                nerrors += (test_can_apply2(file) < 0                ? 1 : 0);
+                nerrors += (test_set_local(my_fapl) < 0                ? 1 : 0);
+                nerrors += (test_can_apply_szip(file) < 0        ? 1 : 0);
+                nerrors += (test_compare_dcpl(file) < 0                ? 1 : 0);
+                nerrors += (test_copy_dcpl(file, my_fapl) < 0            ? 1 : 0);
+                nerrors += (test_filter_delete(file) < 0        ? 1 : 0);
+                nerrors += (test_filters_endianess() < 0            ? 1 : 0);
+                nerrors += (test_zero_dims(file) < 0                ? 1 : 0);
+                nerrors += (test_missing_chunk(file) < 0        ? 1 : 0);
+                nerrors += (test_random_chunks(my_fapl) < 0        ? 1 : 0);
 
 #ifndef H5_NO_DEPRECATED_SYMBOLS
-            nerrors += (test_deprec(file) < 0            ? 1 : 0);
+                nerrors += (test_deprec(file) < 0            ? 1 : 0);
 #endif /* H5_NO_DEPRECATED_SYMBOLS */
 
-            nerrors += (test_huge_chunks(my_fapl) < 0        ? 1 : 0);
-            nerrors += (test_chunk_cache(my_fapl) < 0        ? 1 : 0);
-            nerrors += (test_big_chunks_bypass_cache(my_fapl) < 0   ? 1 : 0);
-            nerrors += (test_chunk_fast(envval, my_fapl) < 0    ? 1 : 0);
-            nerrors += (test_reopen_chunk_fast(my_fapl) < 0        ? 1 : 0);
-            nerrors += (test_chunk_fast_bug1(my_fapl) < 0           ? 1 : 0);
-            nerrors += (test_chunk_expand(my_fapl) < 0        ? 1 : 0);
-            nerrors += (test_layout_extend(my_fapl) < 0        ? 1 : 0);
-            nerrors += (test_fixed_array(my_fapl) < 0        ? 1 : 0);
-            nerrors += (test_idx_compatible() < 0            ? 1 : 0);
-            nerrors += (test_unfiltered_edge_chunks(my_fapl) < 0    ? 1 : 0);
-            nerrors += (test_single_chunk(my_fapl) < 0              ? 1 : 0);
-            nerrors += (test_large_chunk_shrink(my_fapl) < 0        ? 1 : 0);
-            nerrors += (test_zero_dim_dset(my_fapl) < 0             ? 1 : 0);
-            nerrors += (test_storage_size(my_fapl) < 0              ? 1 : 0);
-            nerrors += (test_power2up(my_fapl) < 0                  ? 1 : 0);
-
-            nerrors += (test_swmr_non_latest(envval, my_fapl) < 0   ? 1 : 0);
-            nerrors += (test_earray_hdr_fd(envval, my_fapl) < 0     ? 1 : 0);
-            nerrors += (test_farray_hdr_fd(envval, my_fapl) < 0     ? 1 : 0);
-            nerrors += (test_bt2_hdr_fd(envval, my_fapl) < 0        ? 1 : 0);
-
-            if(H5Fclose(file) < 0)
-                goto error;
-        } /* end for new_format */
+                nerrors += (test_huge_chunks(my_fapl) < 0        ? 1 : 0);
+                nerrors += (test_chunk_cache(my_fapl) < 0        ? 1 : 0);
+                nerrors += (test_big_chunks_bypass_cache(my_fapl) < 0   ? 1 : 0);
+                nerrors += (test_chunk_fast(envval, my_fapl) < 0    ? 1 : 0);
+                nerrors += (test_reopen_chunk_fast(my_fapl) < 0        ? 1 : 0);
+                nerrors += (test_chunk_fast_bug1(my_fapl) < 0           ? 1 : 0);
+                nerrors += (test_chunk_expand(my_fapl) < 0        ? 1 : 0);
+                nerrors += (test_layout_extend(my_fapl) < 0        ? 1 : 0);
+                nerrors += (test_fixed_array(my_fapl) < 0        ? 1 : 0);
+                nerrors += (test_idx_compatible() < 0            ? 1 : 0);
+                nerrors += (test_unfiltered_edge_chunks(my_fapl) < 0    ? 1 : 0);
+                nerrors += (test_single_chunk(my_fapl) < 0              ? 1 : 0);
+                nerrors += (test_large_chunk_shrink(my_fapl) < 0        ? 1 : 0);
+                nerrors += (test_zero_dim_dset(my_fapl) < 0             ? 1 : 0);
+                nerrors += (test_storage_size(my_fapl) < 0              ? 1 : 0);
+                nerrors += (test_power2up(my_fapl) < 0                  ? 1 : 0);
+
+                nerrors += (test_swmr_non_latest(envval, my_fapl) < 0   ? 1 : 0);
+                nerrors += (test_earray_hdr_fd(envval, my_fapl) < 0     ? 1 : 0);
+                nerrors += (test_farray_hdr_fd(envval, my_fapl) < 0     ? 1 : 0);
+                nerrors += (test_bt2_hdr_fd(envval, my_fapl) < 0        ? 1 : 0);
+
+                if(H5Fclose(file) < 0)
+                    goto error;
+            } /* end for new_format */
+        } /* end for minimized_ohdr */
     } /* end for paged */
 
     /* Close property lists */
@@ -13232,7 +13368,9 @@ main(void)
     nerrors += (test_gather_error() < 0                     ? 1 : 0);
 
     /* Tests version bounds using its own file */
-    nerrors += (test_versionbounds() < 0             ? 1 : 0);
+    nerrors += (test_versionbounds() < 0                    ? 1 : 0);
+
+    nerrors += (test_object_header_minimization_dcpl(fapl) < 0 ? 1 : 0);
 
     /* Run misc tests */
     nerrors += dls_01_main();
@@ -13249,12 +13387,12 @@ main(void)
 #endif /* H5_HAVE_FILTER_SZIP */
     h5_cleanup(FILENAME, fapl);
 
-    return 0;
+    return EXIT_SUCCESS;
 
 error:
     nerrors = MAX(1, nerrors);
     printf("***** %d DATASET TEST%s FAILED! *****\n",
             nerrors, 1 == nerrors ? "" : "S");
-    return 1;
-}
+    return EXIT_FAILURE;
+} /* end main() */
 
diff --git a/test/dt_arith.c b/test/dt_arith.c
index c7f2986..2729ba1 100644
--- a/test/dt_arith.c
+++ b/test/dt_arith.c
@@ -4883,7 +4883,24 @@ run_fp_tests(const char *name)
 #if H5_SIZEOF_LONG_DOUBLE!=H5_SIZEOF_DOUBLE && H5_SIZEOF_LONG_DOUBLE!=0
     nerrors += test_conv_flt_1(name, TEST_DENORM, H5T_NATIVE_FLOAT, H5T_NATIVE_LDOUBLE);
     nerrors += test_conv_flt_1(name, TEST_DENORM, H5T_NATIVE_DOUBLE, H5T_NATIVE_LDOUBLE);
+#ifndef H5_DISABLE_SOME_LDOUBLE_CONV
     nerrors += test_conv_flt_1(name, TEST_DENORM, H5T_NATIVE_LDOUBLE, H5T_NATIVE_FLOAT);
+#else
+    {
+        char		str[256];		/*string		*/
+
+        HDsnprintf(str, sizeof(str), "Testing %s denormalized %s -> %s conversions",
+                name, "long double", "float");
+        printf("%-70s", str);
+        SKIPPED();
+#if H5_SIZEOF_LONG_DOUBLE!=0
+        HDputs("    Test skipped due to the conversion problem on IBM ppc64le cpu.");
+#else
+        HDputs("    Test skipped due to disabled long double.");
+#endif
+    }
+#endif
+
     nerrors += test_conv_flt_1(name, TEST_DENORM, H5T_NATIVE_LDOUBLE, H5T_NATIVE_DOUBLE);
 #endif
 
@@ -4893,8 +4910,24 @@ run_fp_tests(const char *name)
 #if H5_SIZEOF_LONG_DOUBLE!=H5_SIZEOF_DOUBLE && H5_SIZEOF_LONG_DOUBLE!=0
     nerrors += test_conv_flt_1(name, TEST_SPECIAL, H5T_NATIVE_FLOAT, H5T_NATIVE_LDOUBLE);
     nerrors += test_conv_flt_1(name, TEST_SPECIAL, H5T_NATIVE_DOUBLE, H5T_NATIVE_LDOUBLE);
+#ifndef H5_DISABLE_SOME_LDOUBLE_CONV
     nerrors += test_conv_flt_1(name, TEST_SPECIAL, H5T_NATIVE_LDOUBLE, H5T_NATIVE_FLOAT);
     nerrors += test_conv_flt_1(name, TEST_SPECIAL, H5T_NATIVE_LDOUBLE, H5T_NATIVE_DOUBLE);
+#else
+    {
+        char		str[256];		/*string		*/
+
+        HDsnprintf(str, sizeof(str), "Testing %s special %s -> %s conversions",
+                name, "long double", "float or double");
+        printf("%-70s", str);
+        SKIPPED();
+#if H5_SIZEOF_LONG_DOUBLE!=0
+        HDputs("    Test skipped due to the conversion problem on IBM ppc64le cpu.");
+#else
+        HDputs("    Test skipped due to disabled long double.");
+#endif
+    }
+#endif
 #endif
 
 done:
@@ -4963,7 +4996,7 @@ run_int_fp_conv(const char *name)
     nerrors += test_conv_int_fp(name, TEST_NORMAL, H5T_NATIVE_INT, H5T_NATIVE_LDOUBLE);
     nerrors += test_conv_int_fp(name, TEST_NORMAL, H5T_NATIVE_UINT, H5T_NATIVE_LDOUBLE);
 #if H5_SIZEOF_LONG!=H5_SIZEOF_INT
-#ifndef H5_LONG_TO_LDOUBLE_SPECIAL
+#if !defined(H5_LONG_TO_LDOUBLE_SPECIAL) && !defined(H5_DISABLE_SOME_LDOUBLE_CONV)
     nerrors += test_conv_int_fp(name, TEST_NORMAL, H5T_NATIVE_LONG, H5T_NATIVE_LDOUBLE);
     nerrors += test_conv_int_fp(name, TEST_NORMAL, H5T_NATIVE_ULONG, H5T_NATIVE_LDOUBLE);
 #else
@@ -5077,16 +5110,46 @@ run_fp_int_conv(const char *name)
 #endif
 
 #if H5_SIZEOF_LONG_DOUBLE!=H5_SIZEOF_DOUBLE
-        nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_SCHAR);
-        nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_UCHAR);
-        nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_SHORT);
-        nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_USHORT);
-        nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_INT);
-        nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_UINT);
+        if(test_values != TEST_SPECIAL) {
+	    nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_SCHAR);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_UCHAR);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_SHORT);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_USHORT);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_INT);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_UINT);
+        } else {
+#ifndef H5_DISABLE_SOME_LDOUBLE_CONV
+	    nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_SCHAR);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_UCHAR);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_SHORT);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_USHORT);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_INT);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_UINT);
+#else
+            char		str[256];		/*string		*/
+
+            HDsnprintf(str, sizeof(str), "Testing %s special %s -> %s conversions",
+                name, "long double", "signed and unsigned char, short, int, long");
+            printf("%-70s", str);
+            SKIPPED();
+#if H5_SIZEOF_LONG_DOUBLE!=0
+            HDputs("    Test skipped due to the conversion problem on IBM ppc64le cpu.");
+#else
+            HDputs("    Test skipped due to disabled long double.");
+#endif
+#endif
+        }
 #if H5_SIZEOF_LONG!=H5_SIZEOF_INT && H5_SIZEOF_LONG_DOUBLE!=0
 #ifndef H5_LDOUBLE_TO_LONG_SPECIAL
-        nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_LONG);
-        nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_ULONG);
+        if(test_values != TEST_SPECIAL && test_values != TEST_NORMAL) {
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_LONG);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_ULONG);
+        } else {
+#ifndef H5_DISABLE_SOME_LDOUBLE_CONV
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_LONG);
+            nerrors += test_conv_int_fp(name, test_values, H5T_NATIVE_LDOUBLE, H5T_NATIVE_ULONG);
+#endif
+        }
 #else
         {
             char		str[256];		/*string		*/
diff --git a/test/enc_dec_plist.c b/test/enc_dec_plist.c
index 36db2d0..cee38f3 100644
--- a/test/enc_dec_plist.c
+++ b/test/enc_dec_plist.c
@@ -146,6 +146,9 @@ main(void)
     if((H5Pset_fill_value(dcpl, H5T_NATIVE_DOUBLE, &fill)) < 0)
         FAIL_STACK_ERROR
 
+    if((H5Pset_dset_no_attrs_hint(dcpl, FALSE)) < 0)
+        FAIL_STACK_ERROR
+
     max_size[0] = 100;
     if((H5Pset_external(dcpl, "ext1.data", (off_t)0, 
                          (hsize_t)(max_size[0] * sizeof(int)/4))) < 0)
diff --git a/test/gen_bogus.c b/test/gen_bogus.c
index ec29eb9..237b024 100644
--- a/test/gen_bogus.c
+++ b/test/gen_bogus.c
@@ -89,6 +89,14 @@ generate_datasets(hid_t loc_id, unsigned bogus_id)
     if((did = H5Dcreate2(loc_id, "Dataset4", H5T_NATIVE_INT, sid, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0) goto error;
     if(H5Dclose(did) < 0) goto error;
 
+    /* Set "shareable" message flag for bogus message */
+    bogus_flags = H5O_MSG_FLAG_SHAREABLE;
+    if(H5Pset(dcpl, H5O_BOGUS_MSG_FLAGS_NAME, &bogus_flags) < 0) goto error;
+
+    /* Create fourth dataset, with "shareable" message flag */
+    if((did = H5Dcreate2(loc_id, "Dataset5", H5T_NATIVE_INT, sid, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0) goto error;
+    if(H5Dclose(did) < 0) goto error;
+
     /* Close dataset creation property list */
     if(H5Pclose(dcpl) < 0) goto error;
 
diff --git a/test/gen_plist.c b/test/gen_plist.c
index 62693bd..d8096e3 100644
--- a/test/gen_plist.c
+++ b/test/gen_plist.c
@@ -125,6 +125,9 @@ main(void)
     if((ret = H5Pset_fill_value(dcpl1, H5T_STD_I32BE, &fill)) < 0)
         assert(ret > 0);
 
+    if((ret = H5Pset_dset_no_attrs_hint(dcpl1, FALSE)) < 0)
+        assert(ret > 0);
+
     max_size[0] = 100;
     if((ret = H5Pset_external(dcpl1, "ext1.data", (off_t)0, 
                          (hsize_t)(max_size[0] * sizeof(int)/4))) < 0)
diff --git a/test/h5test.c b/test/h5test.c
index 687f594..62eb6bf 100644
--- a/test/h5test.c
+++ b/test/h5test.c
@@ -643,7 +643,7 @@ h5_fixname_real(const char *base_name, hid_t fapl, const char *_suffix,
                 printf("*** Hint ***\n"
                        "You can use environment variable HDF5_PARAPREFIX to "
                        "run parallel test files in a\n"
-                       "different directory or to add file type prefix. E.g.,\n"
+                       "different directory or to add file type prefix. e.g.,\n"
                        "   HDF5_PARAPREFIX=pfs:/PFS/user/me\n"
                        "   export HDF5_PARAPREFIX\n"
                        "*** End of Hint ***\n");
@@ -1854,6 +1854,42 @@ static herr_t dummy_vfd_read(H5FD_t H5_ATTR_UNUSED *_file, H5FD_mem_t H5_ATTR_UN
 static herr_t dummy_vfd_write(H5FD_t *_file, H5FD_mem_t type, hid_t fapl_id, haddr_t addr, size_t size, const void *buf);
 static herr_t dummy_vfd_write(H5FD_t H5_ATTR_UNUSED *_file, H5FD_mem_t H5_ATTR_UNUSED type, hid_t H5_ATTR_UNUSED fapl_id, haddr_t H5_ATTR_UNUSED addr, size_t H5_ATTR_UNUSED size, const void H5_ATTR_UNUSED *buf) { return FAIL; }
 
+/* Dummy VFD with the minimum parameters to make a VFD that can be registered */
+static const H5FD_class_t H5FD_dummy_g = {
+    "dummy",                    /* name         */
+    1,                          /* maxaddr      */
+    H5F_CLOSE_WEAK,             /* fc_degree    */
+    NULL,                       /* terminate    */
+    NULL,                       /* sb_size      */
+    NULL,                       /* sb_encode    */
+    NULL,                       /* sb_decode    */
+    0,                          /* fapl_size    */
+    NULL,                       /* fapl_get     */
+    NULL,                       /* fapl_copy    */
+    NULL,                       /* fapl_free    */
+    0,                          /* dxpl_size    */
+    NULL,                       /* dxpl_copy    */
+    NULL,                       /* dxpl_free    */
+    dummy_vfd_open,             /* open         */
+    dummy_vfd_close,            /* close        */
+    NULL,                       /* cmp          */
+    NULL,                       /* query        */
+    NULL,                       /* get_type_map */
+    NULL,                       /* alloc        */
+    NULL,                       /* free         */
+    dummy_vfd_get_eoa,          /* get_eoa      */
+    dummy_vfd_set_eoa,          /* set_eoa      */
+    dummy_vfd_get_eof,          /* get_eof      */
+    NULL,                       /* get_handle   */
+    dummy_vfd_read,             /* read         */
+    dummy_vfd_write,            /* write        */
+    NULL,                       /* flush        */
+    NULL,                       /* truncate     */
+    NULL,                       /* lock         */
+    NULL,                       /* unlock       */
+    H5FD_FLMAP_DICHOTOMY	/* fl_map       */
+};
+
 
 /*-------------------------------------------------------------------------
  * Function:    h5_get_dummy_vfd_class()
@@ -1881,21 +1917,11 @@ h5_get_dummy_vfd_class(void)
     H5FD_class_t *vfd_class = NULL;     /* Dummy VFD that will be returned */
 
     /* Create the class and initialize everything to zero/NULL */
-    if(NULL == (vfd_class = (H5FD_class_t *)HDcalloc((size_t)1, sizeof(H5FD_class_t))))
+    if(NULL == (vfd_class = (H5FD_class_t *)HDmalloc(sizeof(H5FD_class_t))))
         TEST_ERROR;
 
-    /* Fill in the minimum parameters to make a VFD that
-     * can be registered.
-     */
-    vfd_class->name = "dummy";
-    vfd_class->maxaddr = 1;
-    vfd_class->open = dummy_vfd_open;
-    vfd_class->close = dummy_vfd_close;
-    vfd_class->get_eoa = dummy_vfd_get_eoa;
-    vfd_class->set_eoa = dummy_vfd_set_eoa;
-    vfd_class->get_eof = dummy_vfd_get_eof;
-    vfd_class->read = dummy_vfd_read;
-    vfd_class->write = dummy_vfd_write;
+    /* Copy the dummy VFD */
+    HDmemcpy(vfd_class, &H5FD_dummy_g, sizeof(H5FD_class_t));
 
     return vfd_class;
 
diff --git a/test/links.c b/test/links.c
index fb2c75a..63b125f 100644
--- a/test/links.c
+++ b/test/links.c
@@ -315,6 +315,8 @@ typedef struct {
     const obj_visit_t *info;    /* Pointer to the object visit structure to use */
 } ovisit_ud_t;
 
+static hid_t dcpl_g; /* for [un]minimized dataset object headers */
+
 
 
 /*-------------------------------------------------------------------------
@@ -377,7 +379,7 @@ mklinks(hid_t fapl, hbool_t new_format)
     if(H5Gclose(grp) < 0) TEST_ERROR
 
     /* Create a dataset */
-    if((d1 = H5Dcreate2(file, "d1", H5T_NATIVE_INT, scalar, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if((d1 = H5Dcreate2(file, "d1", H5T_NATIVE_INT, scalar, H5P_DEFAULT, dcpl_g, H5P_DEFAULT)) < 0) TEST_ERROR
     if(H5Dclose(d1) < 0) TEST_ERROR
 
     /* Create a hard link */
@@ -451,8 +453,8 @@ new_links(hid_t fapl, hbool_t new_format)
     if((grp2_b = H5Gcreate2(file_b, "grp2", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
 
     /* Create datasets */
-    if((dset1 = H5Dcreate2(file_a, "dataset1", H5T_NATIVE_INT, scalar, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
-    if((dset2 = H5Dcreate2(grp1_a, "dataset2", H5T_NATIVE_INT, scalar, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if((dset1 = H5Dcreate2(file_a, "dataset1", H5T_NATIVE_INT, scalar, H5P_DEFAULT, dcpl_g, H5P_DEFAULT)) < 0) TEST_ERROR
+    if((dset2 = H5Dcreate2(grp1_a, "dataset2", H5T_NATIVE_INT, scalar, H5P_DEFAULT, dcpl_g, H5P_DEFAULT)) < 0) TEST_ERROR
 
     /* Create links within a file.  Both of source and destination use
      * H5L_SAME_LOC.  Both hard and soft links should fail. */
@@ -545,7 +547,7 @@ cklinks(hid_t fapl, hbool_t new_format)
     if(H5Oget_info_by_name2(file, "grp1/hard", &oinfo2, H5O_INFO_BASIC, H5P_DEFAULT) < 0) FAIL_STACK_ERROR
     if(H5O_TYPE_DATASET != oinfo2.type) {
 	H5_FAILED();
-	printf("    %d: Unexpected object type should have been a dataset\n", __LINE__);
+	HDprintf("    %d: Unexpected object type should have been a dataset\n", __LINE__);
 	TEST_ERROR
     } /* end if */
     if(H5F_addr_ne(oinfo1.addr, oinfo2.addr)) {
@@ -580,7 +582,7 @@ cklinks(hid_t fapl, hbool_t new_format)
     if(H5Oget_info_by_name2(file, "grp1/soft", &oinfo2, H5O_INFO_BASIC, H5P_DEFAULT) < 0) FAIL_STACK_ERROR
     if(H5O_TYPE_DATASET != oinfo2.type) {
 	H5_FAILED();
-	printf("    %d: Unexpected object type should have been a dataset\n", __LINE__);
+	HDprintf("    %d: Unexpected object type should have been a dataset\n", __LINE__);
 	TEST_ERROR
     } /* end if */
     if(H5F_addr_ne(oinfo1.addr, oinfo2.addr)) {
@@ -609,12 +611,12 @@ cklinks(hid_t fapl, hbool_t new_format)
     if(H5Lget_info(file, "grp1/dangle", &linfo2, H5P_DEFAULT) < 0) FAIL_STACK_ERROR
     if(H5L_TYPE_SOFT != linfo2.type) {
 	H5_FAILED();
-	printf("    %d: Unexpected object type should have been a symbolic link\n", __LINE__);
+	HDprintf("    %d: Unexpected object type should have been a symbolic link\n", __LINE__);
 	TEST_ERROR
     } /* end if */
     if(H5Lget_val(file, "grp1/dangle", linkval, sizeof linkval, H5P_DEFAULT) < 0) {
 	H5_FAILED();
-	printf("    %d: Can't retrieve link value\n", __LINE__);
+	HDprintf("    %d: Can't retrieve link value\n", __LINE__);
 	TEST_ERROR
     } /* end if */
     if(HDstrcmp(linkval, "foobar")) {
@@ -1014,7 +1016,7 @@ test_lcpl(hid_t fapl, hbool_t new_format)
     if((space_id=H5Screate_simple(2 ,dims, NULL)) < 0) TEST_ERROR
 
     /* Create a dataset using the default LCPL */
-    if((dset_id = H5Dcreate2(file_id, "/dataset", H5T_NATIVE_INT, space_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if((dset_id = H5Dcreate2(file_id, "/dataset", H5T_NATIVE_INT, space_id, H5P_DEFAULT, dcpl_g, H5P_DEFAULT)) < 0) TEST_ERROR
     if(H5Dclose(dset_id) < 0) TEST_ERROR
 
     /* Check that its character encoding is the default */
@@ -1043,7 +1045,7 @@ test_lcpl(hid_t fapl, hbool_t new_format)
     if(linfo.cset != H5T_CSET_UTF8) TEST_ERROR
 
     /* Create a dataset using the new LCPL */
-    if((dset_id = H5Dcreate2(file_id, "/dataset2", H5T_NATIVE_INT, space_id, lcpl_id, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if((dset_id = H5Dcreate2(file_id, "/dataset2", H5T_NATIVE_INT, space_id, lcpl_id, dcpl_g, H5P_DEFAULT)) < 0) TEST_ERROR
     if(H5Dclose(dset_id) < 0) TEST_ERROR
 
     /* Check that its character encoding is UTF-8 */
@@ -2602,7 +2604,7 @@ external_link_toomany(hid_t fapl, hbool_t new_format)
     } H5E_END_TRY;
     if (gid >= 0) {
 	H5_FAILED();
-	printf("%d:    Should have failed for sequence of too many nested links.", __LINE__);
+	HDprintf("%d:    Should have failed for sequence of too many nested links.", __LINE__);
 	goto error;
     }
 
@@ -3758,7 +3760,7 @@ external_set_elink_fapl2(hid_t fapl, hbool_t new_format)
     if((space = H5Screate_simple(2, dims, NULL)) < 0) TEST_ERROR
 
     /* Create dataset creation property list */
-    if((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0) TEST_ERROR;
+    if((dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g)) < 0) TEST_ERROR;
     if(H5Pset_alloc_time(dcpl, H5D_ALLOC_TIME_LATE) < 0) TEST_ERROR;
 
     /* create "Dataset" in group "A" of target file */
@@ -6100,7 +6102,7 @@ external_link_closing(hid_t fapl, hbool_t new_format)
     /* Test creating each kind of object */
     if((gid = H5Gcreate2(fid1, "elink/elink/elink/group1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
     if(H5Tcommit2(fid1, "elink/elink/elink/type1", tid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT) < 0) TEST_ERROR
-    if((did = H5Dcreate2(fid1, "elink/elink/elink/dataset1", tid2, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if((did = H5Dcreate2(fid1, "elink/elink/elink/dataset1", tid2, sid, H5P_DEFAULT, dcpl_g, H5P_DEFAULT)) < 0) TEST_ERROR
 
     /* Close objects */
     if(H5Gclose(gid) < 0) TEST_ERROR
@@ -7298,7 +7300,7 @@ external_open_twice(hid_t fapl, hbool_t new_format)
     if((space = H5Screate(H5S_SCALAR)) < 0)
         TEST_ERROR
     if((oid1 = H5Dcreate2(fid2, "dset", H5T_NATIVE_INT, space, H5P_DEFAULT,
-            H5P_DEFAULT, H5P_DEFAULT)) < 0)
+            dcpl_g, H5P_DEFAULT)) < 0)
         TEST_ERROR
     if(H5Dclose(oid1) < 0)
         TEST_ERROR
@@ -7514,7 +7516,7 @@ external_link_with_committed_datatype(hid_t fapl, hbool_t new_format)
     if((sid2 = H5Screate_simple(2, dims, NULL)) < 0)
         FAIL_STACK_ERROR
 
-    if((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
+    if((dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g)) < 0)
         FAIL_STACK_ERROR
     if(H5Pset_chunk(dcpl, 2, chunks) < 0)
         FAIL_STACK_ERROR
@@ -9058,7 +9060,7 @@ lapl_nlinks(hid_t fapl, hbool_t new_format)
     dims[0] = 2;
     dims[1] = 2;
     if((sid = H5Screate_simple(2, dims, NULL)) < 0) TEST_ERROR
-    if((did = H5Dcreate2(gid, "dataset", H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if((did = H5Dcreate2(gid, "dataset", H5T_NATIVE_INT, sid, H5P_DEFAULT, dcpl_g, H5P_DEFAULT)) < 0) TEST_ERROR
     if(H5Dclose(did) < 0) TEST_ERROR
 
     /* Close group */
@@ -9170,7 +9172,7 @@ linkinfo(hid_t fapl, hbool_t new_format)
     if(H5Lcreate_soft("group", fid, "softlink", H5P_DEFAULT, H5P_DEFAULT) < 0) FAIL_STACK_ERROR
 
     if((sid = H5Screate(H5S_SCALAR)) < 0) TEST_ERROR
-    if((did = H5Dcreate2(fid, "dataset", H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if((did = H5Dcreate2(fid, "dataset", H5T_NATIVE_INT, sid, H5P_DEFAULT, dcpl_g, H5P_DEFAULT)) < 0) TEST_ERROR
 
     if(H5Lcreate_ud(fid, "ud_link", (H5L_type_t)UD_PLIST_TYPE, NULL, (size_t)0, H5P_DEFAULT, H5P_DEFAULT) < 0) TEST_ERROR
     if(H5Lcreate_external("file_name", "obj_path", fid, "ext_link", H5P_DEFAULT, H5P_DEFAULT) < 0) TEST_ERROR
@@ -9335,13 +9337,13 @@ build_visit_file(hid_t fapl)
     /* Create dataset in each group */
     if((sid = H5Screate(H5S_SCALAR)) < 0) TEST_ERROR
 
-    if((did = H5Dcreate2(fid, "/Dataset_zero", H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if((did = H5Dcreate2(fid, "/Dataset_zero", H5T_NATIVE_INT, sid, H5P_DEFAULT, dcpl_g, H5P_DEFAULT)) < 0) TEST_ERROR
     if(H5Dclose(did) < 0) TEST_ERROR
 
-    if((did = H5Dcreate2(fid, "/Group1/Dataset_one", H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if((did = H5Dcreate2(fid, "/Group1/Dataset_one", H5T_NATIVE_INT, sid, H5P_DEFAULT, dcpl_g, H5P_DEFAULT)) < 0) TEST_ERROR
     if(H5Dclose(did) < 0) TEST_ERROR
 
-    if((did = H5Dcreate2(fid, "/Group1/Group2/Dataset_two", H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
+    if((did = H5Dcreate2(fid, "/Group1/Group2/Dataset_two", H5T_NATIVE_INT, sid, H5P_DEFAULT, dcpl_g, H5P_DEFAULT)) < 0) TEST_ERROR
     if(H5Dclose(did) < 0) TEST_ERROR
 
     if(H5Sclose(sid) < 0) TEST_ERROR
@@ -14890,6 +14892,7 @@ main(void)
     hid_t	fapl, fapl2;    /* File access property lists */
     int	nerrors = 0;
     unsigned new_format;    /* Whether to use the new format or not */
+    unsigned minimize_dset_oh; /* Whether to minimize dataset object headers */
     unsigned efc;           /* Whether to use the external file cache */
     const char  *env_h5_drvr;      /* File Driver value from environment */
 
@@ -14900,166 +14903,185 @@ main(void)
     h5_reset();
     fapl = h5_fileaccess();
 
-    /* Copy the file access property list */
+    /* fapl2 uses "latest version bounds" */
     if((fapl2 = H5Pcopy(fapl)) < 0) TEST_ERROR
-
-    /* Set the "use the latest version of the format" bounds for creating objects in the file */
     if(H5Pset_libver_bounds(fapl2, H5F_LIBVER_LATEST, H5F_LIBVER_LATEST) < 0) TEST_ERROR
 
-    /* Loop over using new group format */
-    for(new_format = FALSE; new_format <= TRUE; new_format++) {
-        hid_t my_fapl;
+    for (minimize_dset_oh = 0; minimize_dset_oh <= 1; minimize_dset_oh++) {
+        if (minimize_dset_oh) {
+            HDprintf("\n-Testing with minimzed dataset object headers-\n");
+            dcpl_g = H5Pcreate(H5P_DATASET_CREATE);
+            if (0 > dcpl_g) TEST_ERROR
+        } else {
+            HDprintf("\n-Testing with unminimzed dataset object headers-\n");
+            dcpl_g = H5P_DEFAULT;
+        }
 
-        /* Check for FAPL to use */
-        if(new_format)
-            my_fapl = fapl2;
-        else
-            my_fapl = fapl;
-
-        /* General tests... (on both old & new format groups */
-        nerrors += mklinks(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += cklinks(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += new_links(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += ck_new_links(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += long_links(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += toomany(my_fapl, new_format) < 0 ? 1 : 0;
-
-        /* Test new H5L link creation routine */
-        nerrors += test_lcpl(my_fapl, new_format);
-        nerrors += test_move(my_fapl, new_format);
-        nerrors += test_copy(my_fapl, new_format);
-        nerrors += test_move_preserves(my_fapl, new_format);
+        for(new_format = FALSE; new_format <= TRUE; new_format++) {
+            hid_t my_fapl;
+
+            /* Check for FAPL to use */
+            if(new_format) {
+                my_fapl = fapl2;
+                HDprintf("\n--Testing with 'new format'--\n");
+            } else {
+                my_fapl = fapl;
+                HDprintf("\n--Testing with 'old format'--\n");
+            }
+
+            /* always enter tests without external cache */
+            if(H5Pset_elink_file_cache_size(my_fapl, 0) < 0)
+                TEST_ERROR
+
+            /* General tests... (on both old & new format groups */
+            nerrors += mklinks(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += cklinks(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += new_links(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += ck_new_links(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += long_links(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += toomany(my_fapl, new_format) < 0 ? 1 : 0;
+
+            /* Test new H5L link creation routine */
+            nerrors += test_lcpl(my_fapl, new_format);
+            nerrors += test_move(my_fapl, new_format);
+            nerrors += test_copy(my_fapl, new_format);
+            nerrors += test_move_preserves(my_fapl, new_format);
 #ifndef H5_NO_DEPRECATED_SYMBOLS
-        nerrors += test_deprec(my_fapl, new_format);
+            nerrors += test_deprec(my_fapl, new_format);
 #endif /* H5_NO_DEPRECATED_SYMBOLS */
 
-        /* tests for external link */
-        /* Test external file cache first, so it sees the default efc setting on
-         * the fapl */
-        nerrors += external_file_cache(my_fapl, new_format) < 0 ? 1 : 0;
-
-        /* This test cannot run with the EFC because it assumes that an
-         * intermediate file is not held open */
-        nerrors += external_link_mult(my_fapl, new_format) < 0 ? 1 : 0;
-
-        /* This test cannot run with the EFC because the EFC cannot currently
-         * reopen a cached file with a different intent */
-        nerrors += external_set_elink_acc_flags(env_h5_drvr, my_fapl, new_format) < 0 ? 1 : 0;
-
-        /* Try external link tests both with and without the external file cache
-         */
-        for(efc = FALSE; efc <= TRUE; efc++) {
-            if(efc) {
-                if(H5Pset_elink_file_cache_size(my_fapl, 8) < 0)
-                    TEST_ERROR
-                printf("\n---Testing with external file cache---\n");
-            } /* end if */
-            else {
-                if(H5Pset_elink_file_cache_size(my_fapl, 0) < 0)
-                    TEST_ERROR
-                printf("\n---Testing without external file cache---\n");
-            } /* end else */
+            /* tests for external link */
+            /* Test external file cache first, so it sees the default efc setting on
+             * the fapl */
+            nerrors += external_file_cache(my_fapl, new_format) < 0 ? 1 : 0;
+
+            /* This test cannot run with the EFC because it assumes that an
+             * intermediate file is not held open */
+            nerrors += external_link_mult(my_fapl, new_format) < 0 ? 1 : 0;
+
+            /* This test cannot run with the EFC because the EFC cannot currently
+             * reopen a cached file with a different intent */
+            nerrors += external_set_elink_acc_flags(env_h5_drvr, my_fapl, new_format) < 0 ? 1 : 0;
+
+            /* Try external link tests both with and without the external file cache
+             */
+            for(efc = FALSE; efc <= TRUE; efc++) {
+                if(efc) {
+                    if(H5Pset_elink_file_cache_size(my_fapl, 8) < 0)
+                        TEST_ERROR
+                    HDprintf("\n---Testing with external file cache---\n");
+                } /* end if */
+                else {
+                    if(H5Pset_elink_file_cache_size(my_fapl, 0) < 0)
+                        TEST_ERROR
+                    HDprintf("\n---Testing without external file cache---\n");
+                } /* end else */
 
-            nerrors += external_link_root(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_path(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_self(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_pingpong(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_toomany(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_dangling(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_recursive(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_query(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_unlink_compact(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_unlink_dense(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_move(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_ride(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_closing(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_endian(new_format) < 0 ? 1 : 0;
-            nerrors += external_link_strong(my_fapl, new_format) < 0 ? 1 : 0;
-
-            nerrors += external_link_prefix(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_abs_mainpath(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_rel_mainpath(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_cwd(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_abstar(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_abstar_cur(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_reltar(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_chdir(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_set_elink_fapl1(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_set_elink_fapl2(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_set_elink_fapl3(new_format) < 0 ? 1 : 0;
-            nerrors += external_set_elink_cb(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_root(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_path(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_self(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_pingpong(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_toomany(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_dangling(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_recursive(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_query(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_unlink_compact(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_unlink_dense(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_move(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_ride(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_closing(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_endian(new_format) < 0 ? 1 : 0;
+                nerrors += external_link_strong(my_fapl, new_format) < 0 ? 1 : 0;
+
+                nerrors += external_link_prefix(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_abs_mainpath(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_rel_mainpath(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_cwd(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_abstar(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_abstar_cur(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_reltar(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_chdir(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_set_elink_fapl1(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_set_elink_fapl2(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_set_elink_fapl3(new_format) < 0 ? 1 : 0;
+                nerrors += external_set_elink_cb(my_fapl, new_format) < 0 ? 1 : 0;
 #ifdef H5_HAVE_WINDOW_PATH
-            nerrors += external_link_win1(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_win2(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_win3(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_win4(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_win5(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_win6(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_win7(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_win8(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_link_win9(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_win1(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_win2(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_win3(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_win4(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_win5(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_win6(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_win7(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_win8(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_link_win9(my_fapl, new_format) < 0 ? 1 : 0;
 #endif
-            nerrors += external_symlink(env_h5_drvr, my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_copy_invalid_object(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_dont_fail_to_source(my_fapl, new_format) < 0 ? 1 : 0;
-            nerrors += external_open_twice(my_fapl, new_format) < 0 ? 1 : 0;
-	    nerrors += external_link_with_committed_datatype(my_fapl, new_format) < 0 ? 1 : 0;
-        } /* end for */
-
-        /* These tests assume that external links are a form of UD links,
-         * so assume that everything that passed for external links
-         * above has already been tested for UD links.
-         */
-        if(new_format == TRUE) {
-            nerrors += ud_hard_links(fapl2) < 0 ? 1 : 0;     /* requires new format groups */
-            nerrors += ud_link_reregister(fapl2) < 0 ? 1 : 0;        /* requires new format groups */
-        } /* end if */
-        nerrors += ud_callbacks(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += ud_link_errors(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += lapl_udata(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += lapl_nlinks(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += linkinfo(my_fapl, new_format) < 0 ? 1 : 0;
-
-        /* Misc. extra tests, useful for both new & old format files */
-        nerrors += link_visit(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += link_visit_by_name(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += obj_visit(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += obj_visit_by_name(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += obj_visit_stop(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += link_filters(my_fapl, new_format) < 0 ? 1 : 0;
-        nerrors += obj_exists(my_fapl, new_format) < 0 ? 1 : 0;
-
-        /* Keep this test last, it's testing files that are used above */
-        /* do not do this for files used by external link tests */
-        nerrors += check_all_closed(my_fapl, new_format, EXTSTOP) < 0 ? 1 : 0;
-    } /* end for */
-
-    /* New group revision feature tests */
-    nerrors += corder_create_empty(fapl2) < 0 ? 1 : 0;
+                nerrors += external_symlink(env_h5_drvr, my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_copy_invalid_object(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_dont_fail_to_source(my_fapl, new_format) < 0 ? 1 : 0;
+                nerrors += external_open_twice(my_fapl, new_format) < 0 ? 1 : 0;
+	        nerrors += external_link_with_committed_datatype(my_fapl, new_format) < 0 ? 1 : 0;
+            } /* for with/without external file cache (efc) */
+
+            /* These tests assume that external links are a form of UD links,
+             * so assume that everything that passed for external links
+             * above has already been tested for UD links.
+             */
+            if(new_format == TRUE) {
+                nerrors += ud_hard_links(fapl2) < 0 ? 1 : 0;     /* requires new format groups */
+                nerrors += ud_link_reregister(fapl2) < 0 ? 1 : 0;        /* requires new format groups */
+            } /* end if */
+            nerrors += ud_callbacks(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += ud_link_errors(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += lapl_udata(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += lapl_nlinks(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += linkinfo(my_fapl, new_format) < 0 ? 1 : 0;
+
+            /* Misc. extra tests, useful for both new & old format files */
+            nerrors += link_visit(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += link_visit_by_name(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += obj_visit(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += obj_visit_by_name(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += obj_visit_stop(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += link_filters(my_fapl, new_format) < 0 ? 1 : 0;
+            nerrors += obj_exists(my_fapl, new_format) < 0 ? 1 : 0;
+
+            /* Keep this test last, it's testing files that are used above */
+            /* do not do this for files used by external link tests */
+            nerrors += check_all_closed(my_fapl, new_format, EXTSTOP) < 0 ? 1 : 0;
+        } /* for new/old format */
+
+        /* New group revision feature tests */
+        nerrors += corder_create_empty(fapl2) < 0 ? 1 : 0;
 /* XXX: when creation order indexing is fully working, go back and add checks
 *      to these tests to make certain that the creation order values are
 *      correct.
 */
-    nerrors += corder_create_compact(fapl2) < 0 ? 1 : 0;
-    nerrors += corder_create_dense(fapl2) < 0 ? 1 : 0;
-    nerrors += corder_transition(fapl2) < 0 ? 1 : 0;
-    nerrors += corder_delete(fapl2) < 0 ? 1 : 0;
-    nerrors += link_info_by_idx(fapl2) < 0 ? 1 : 0;
-    nerrors += delete_by_idx(fapl2) < 0 ? 1 : 0;
-    nerrors += link_iterate(fapl2) < 0 ? 1 : 0;
-    nerrors += open_by_idx(fapl2) < 0 ? 1 : 0;
-    nerrors += object_info(fapl2) < 0 ? 1 : 0;
-    nerrors += group_info(fapl2) < 0 ? 1 : 0;
-    nerrors += timestamps(fapl2) < 0 ? 1 : 0;
-
-    /* Test new API calls on old-style groups */
-    nerrors += link_info_by_idx_old(fapl) < 0 ? 1 : 0;
-    nerrors += delete_by_idx_old(fapl) < 0 ? 1 : 0;
-    nerrors += link_iterate_old(fapl) < 0 ? 1 : 0;
-    nerrors += open_by_idx_old(fapl) < 0 ? 1 : 0;
-    nerrors += object_info_old(fapl) < 0 ? 1 : 0;
-    nerrors += group_info_old(fapl) < 0 ? 1 : 0;
-
+        nerrors += corder_create_compact(fapl2) < 0 ? 1 : 0;
+        nerrors += corder_create_dense(fapl2) < 0 ? 1 : 0;
+        nerrors += corder_transition(fapl2) < 0 ? 1 : 0;
+        nerrors += corder_delete(fapl2) < 0 ? 1 : 0;
+        nerrors += link_info_by_idx(fapl2) < 0 ? 1 : 0;
+        nerrors += delete_by_idx(fapl2) < 0 ? 1 : 0;
+        nerrors += link_iterate(fapl2) < 0 ? 1 : 0;
+        nerrors += open_by_idx(fapl2) < 0 ? 1 : 0;
+        nerrors += object_info(fapl2) < 0 ? 1 : 0;
+        nerrors += group_info(fapl2) < 0 ? 1 : 0;
+        nerrors += timestamps(fapl2) < 0 ? 1 : 0;
+
+        /* Test new API calls on old-style groups */
+        nerrors += link_info_by_idx_old(fapl) < 0 ? 1 : 0;
+        nerrors += delete_by_idx_old(fapl) < 0 ? 1 : 0;
+        nerrors += link_iterate_old(fapl) < 0 ? 1 : 0;
+        nerrors += open_by_idx_old(fapl) < 0 ? 1 : 0;
+        nerrors += object_info_old(fapl) < 0 ? 1 : 0;
+        nerrors += group_info_old(fapl) < 0 ? 1 : 0;
+
+        if (minimize_dset_oh) {
+            if (H5Pclose(dcpl_g) < 0) TEST_ERROR;
+            dcpl_g = -1;
+        }
+    } /* for [un]minimized dataset object headers */
     /* Close 2nd FAPL */
     H5Pclose(fapl2);
 
@@ -15075,11 +15097,11 @@ main(void)
 
     /* Results */
     if(nerrors) {
-        printf("***** %d LINK TEST%s FAILED! *****\n",
+        HDprintf("***** %d LINK TEST%s FAILED! *****\n",
                 nerrors, 1 == nerrors ? "" : "S");
         HDexit(EXIT_FAILURE);
     }
-    printf("All link tests passed.\n");
+    HDprintf("All link tests passed.\n");
 
     /* clean up symlink created by external link tests */
     HDremove(SYMLINK1);
diff --git a/test/ohdr.c b/test/ohdr.c
index 669b1e0..3f61660 100644
--- a/test/ohdr.c
+++ b/test/ohdr.c
@@ -35,9 +35,16 @@
 
 const char *FILENAME[] = {
     "ohdr",
+    "ohdr_min_a",
+    "ohdr_min_b",
     NULL
 };
 
+/* used for object header size comparison */
+#define EQ 1
+#define LT 2
+#define GT 3
+
 /* The tbogus.h5 is generated from gen_bogus.c in HDF5 'test' directory.
  * To get this data file, define H5O_ENABLE_BOGUS in src/H5Oprivate, rebuild
  * the library and simply compile gen_bogus.c with that HDF5 library and run it.
@@ -50,6 +57,885 @@ const char *FILENAME[] = {
 #define OBJ_VERSION_LATEST 2
 
 /*
+ * Set an attribute with the given information.
+ * If the out parameter `attr_id` is negative, a new attribute will be
+ * created with the given information. Else, it will attempt to update the
+ * attribute with the new value.
+ *
+ * `dataspace_id` ignored if `attribute_id` >= 0
+ */
+static herr_t
+put_attribute(hid_t loc_id, const char *attrname, const void *attrvalue, hid_t datatype_id, hid_t dataspace_id, hid_t *attribute_id)
+{
+    if((*attribute_id) < 0) {
+        hid_t id = -1;
+        id = H5Acreate2(loc_id, attrname, datatype_id, dataspace_id, H5P_DEFAULT, H5P_DEFAULT);
+        if(id < 0)
+            return FAIL;
+        *attribute_id = id;
+    }
+    return H5Awrite(*attribute_id, datatype_id, attrvalue);
+} /* put_attribute */
+
+/*
+ * Count the number of attributes attached to an object.
+ * Returns negative in event of error.
+ */
+static int
+count_attributes(hid_t dset_id)
+{
+    H5O_info_t info;
+
+    if(H5Oget_info2(dset_id, &info, H5O_INFO_ALL) < 0)
+        return -1;
+    else
+        return (int)info.num_attrs; /* should never exceed int bounds */
+} /* count_attributes */
+
+/*
+ * Get the total space used by the object header.
+ * Used by oh_compare()
+ * On success, stores size in `size_out` pointer.
+ */
+static herr_t
+_oh_getsize(hid_t did, hsize_t *size_out)
+{
+    H5O_info_t info;
+    if(FAIL == H5Oget_info2(did, &info, H5O_INFO_HDR))
+        return FAIL;
+    *size_out = info.hdr.space.total;
+    return SUCCEED;
+} /* _oh_getsize */
+
+/*
+ * Compare the TOTAL space used by datasets' object headers.
+ * Returns negative value if an error occurred,
+ * else positive #defined indicator value EQ, LT, GT.
+ */
+static int
+oh_compare(hid_t did1, hid_t did2)
+{
+    hsize_t space1 = 0;
+    hsize_t space2 = 0;
+
+    if(FAIL == _oh_getsize(did1, &space1))
+        return -1;
+    if(FAIL == _oh_getsize(did2, &space2))
+        return -2;
+
+    if(space1 < space2)
+        return LT;
+    else if(space1 > space2)
+        return GT;
+    else
+        return EQ;
+} /* oh_compare() */
+
+/*
+ * Demonstrate attribute addition to datasets.
+ * Conduct additions side-by-side with a standard datataset and one with
+ * minimized dataset object headers.
+ */
+static herr_t
+test_minimized_dset_ohdr_attribute_addition(hid_t fapl_id)
+{
+    hsize_t array_10[1]      = {10}; /* dataspace extent */
+    char    buffer[10]       = "";   /* to inspect string attribute */
+    int     a_out            = 0;
+    char    filename[512]    = "";
+    hid_t   int_type_id      = -1;
+    hid_t   char_type_id     = -1;
+    hid_t   dcpl_id          = -1;
+    hid_t   dspace_id        = -1;
+    hid_t   dspace_scalar_id = -1;
+    hid_t   dset_id          = -1;
+    hid_t   mindset_id       = -1;
+    hid_t   attr_1_id        = -1;
+    hid_t   attr_1a_id       = -1;
+    hid_t   attr_2_id        = -1;
+    hid_t   attr_2a_id       = -1;
+    hid_t   attr_3_id        = -1;
+    hid_t   attr_3a_id       = -1;
+    hid_t   file_id          = -1;
+    herr_t  ret;
+    int     count = 0;
+
+    TESTING("minimized dset object headers attribute additions")
+
+    /*********
+     * SETUP *
+     *********/
+
+    if(h5_fixname(FILENAME[1], fapl_id, filename, sizeof(filename)) == NULL)
+        TEST_ERROR
+
+    dspace_id = H5Screate_simple(1, array_10, NULL);
+    if(dspace_id < 0) TEST_ERROR
+
+    dspace_scalar_id = H5Screate(H5S_SCALAR);
+    if(dspace_scalar_id < 0) TEST_ERROR
+
+    char_type_id = H5Tcopy(H5T_NATIVE_CHAR);
+    if(char_type_id < 0) TEST_ERROR
+
+    int_type_id = H5Tcopy(H5T_NATIVE_INT);
+    if(int_type_id < 0) TEST_ERROR
+
+    dcpl_id = H5Pcreate(H5P_DATASET_CREATE);
+    if(dcpl_id < 0) TEST_ERROR
+
+    ret = H5Pset_dset_no_attrs_hint(dcpl_id, TRUE);
+    if(ret < 0) TEST_ERROR
+
+    file_id = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl_id);
+    if(file_id < 0) TEST_ERROR
+
+    H5E_BEGIN_TRY {
+        count = count_attributes(dset_id);
+    } H5E_END_TRY;
+    if(count != -1) TEST_ERROR
+
+    dset_id = H5Dcreate2(file_id, "dataset", int_type_id, dspace_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    if(dset_id < 0) TEST_ERROR
+
+    mindset_id  = H5Dcreate2(file_id, "mindataset", int_type_id, dspace_id, H5P_DEFAULT, dcpl_id, H5P_DEFAULT);
+    if(mindset_id < 0) TEST_ERROR
+
+    /********************
+     * TEST/DEMONSTRATE *
+     ********************/
+
+    /* -------------------
+     * no attributes added
+     */
+
+    count = count_attributes(dset_id);
+    if(count != 0) TEST_ERROR
+    count = count_attributes(mindset_id);
+    if(count != 0) TEST_ERROR
+
+    /* -----------------
+     * add one attribute
+     */
+    ret = put_attribute(dset_id, "PURPOSE", "DEMO", char_type_id, dspace_id, &attr_1_id);
+    if(ret < 0) TEST_ERROR
+
+    ret = put_attribute(mindset_id, "PURPOSE", "DEMO", char_type_id, dspace_id, &attr_1a_id);
+    if(ret < 0) TEST_ERROR
+
+    count = count_attributes(dset_id);
+    if(count != 1) TEST_ERROR
+    count = count_attributes(mindset_id);
+    if(count != 1) TEST_ERROR
+
+    ret = H5Aread(attr_1_id, char_type_id, buffer);
+    if(ret < 0) TEST_ERROR
+    if(HDstrcmp("DEMO", buffer)) TEST_ERROR
+
+    ret = H5Aread(attr_1a_id, char_type_id, buffer);
+    if(ret < 0) TEST_ERROR
+    if(HDstrcmp("DEMO", buffer)) TEST_ERROR
+
+    /* -----------------
+     * modify one attribute
+     */
+
+    ret = put_attribute(dset_id, "PURPOSE", "REWRITE", char_type_id, -1, &attr_1_id);
+    if(ret < 0) TEST_ERROR
+
+    ret = put_attribute(mindset_id, "PURPOSE", "REWRITE", char_type_id, -1, &attr_1a_id);
+    if(ret < 0) TEST_ERROR
+
+    count = count_attributes(dset_id);
+    if(count != 1) TEST_ERROR
+    count = count_attributes(mindset_id);
+    if(count != 1) TEST_ERROR
+
+    ret = H5Aread(attr_1_id, char_type_id, buffer);
+    if(ret < 0) TEST_ERROR
+    if(HDstrcmp("REWRITE", buffer)) TEST_ERROR
+
+    ret = H5Aread(attr_1a_id, char_type_id, buffer);
+    if(ret < 0) TEST_ERROR
+    if(HDstrcmp("REWRITE", buffer)) TEST_ERROR
+
+    /* -----------------
+     * add second attribute
+     */
+
+    a_out = 5;
+    ret = put_attribute(dset_id, "RANK", &a_out, int_type_id, dspace_scalar_id, &attr_2_id);
+    if(ret < 0) TEST_ERROR
+
+    a_out = 3;
+    ret = put_attribute(mindset_id, "RANK", &a_out, int_type_id, dspace_scalar_id, &attr_2a_id);
+    if(ret < 0) TEST_ERROR
+
+    count = count_attributes(dset_id);
+    if(count != 2) TEST_ERROR
+    count = count_attributes(mindset_id);
+    if(count != 2) TEST_ERROR
+
+    ret = H5Aread(attr_2_id, int_type_id, &a_out);
+    if(ret < 0) TEST_ERROR
+    if(a_out != 5) TEST_ERROR
+
+    ret = H5Aread(attr_2a_id, int_type_id, &a_out);
+    if(ret < 0) TEST_ERROR
+    if(a_out != 3) TEST_ERROR
+
+    /* -----------------
+     * add third attribute
+     */
+
+    a_out = -86;
+    ret = put_attribute(dset_id, "FLAVOR", &a_out, int_type_id, dspace_scalar_id, &attr_3_id);
+    if(ret < 0) TEST_ERROR
+
+    a_out = 2185;
+    ret = put_attribute(mindset_id, "FLAVOR", &a_out, int_type_id, dspace_scalar_id, &attr_3a_id);
+    if(ret < 0) TEST_ERROR
+
+    count = count_attributes(dset_id);
+    if(count != 3) TEST_ERROR
+    count = count_attributes(mindset_id);
+    if(count != 3) TEST_ERROR
+
+    ret = H5Aread(attr_3_id, int_type_id, &a_out);
+    if(ret < 0) TEST_ERROR
+    if(a_out != -86) TEST_ERROR
+
+    ret = H5Aread(attr_3a_id, int_type_id, &a_out);
+    if(ret < 0) TEST_ERROR
+    if(a_out != 2185) TEST_ERROR
+
+    /************
+     * TEARDOWN *
+     ************/
+
+    if(H5Tclose(int_type_id) < 0) TEST_ERROR
+    if(H5Tclose(char_type_id) < 0) TEST_ERROR
+    if(H5Pclose(dcpl_id) < 0) TEST_ERROR
+    if(H5Sclose(dspace_id) < 0) TEST_ERROR
+    if(H5Dclose(dset_id) < 0) TEST_ERROR
+    if(H5Dclose(mindset_id) < 0) TEST_ERROR
+    if(H5Aclose(attr_1_id) < 0) TEST_ERROR
+    if(H5Aclose(attr_1a_id) < 0) TEST_ERROR
+    if(H5Aclose(attr_2_id) < 0) TEST_ERROR
+    if(H5Aclose(attr_2a_id) < 0) TEST_ERROR
+    if(H5Aclose(attr_3_id) < 0) TEST_ERROR
+    if(H5Aclose(attr_3a_id) < 0) TEST_ERROR
+    if(H5Fclose(file_id) < 0) TEST_ERROR
+
+    PASSED()
+    return SUCCEED;
+
+error :
+    H5E_BEGIN_TRY {
+        (void)H5Tclose(int_type_id);
+        (void)H5Tclose(char_type_id);
+        (void)H5Pclose(dcpl_id);
+        (void)H5Sclose(dspace_id);
+        (void)H5Dclose(dset_id);
+        (void)H5Dclose(mindset_id);
+        (void)H5Aclose(attr_1_id);
+        (void)H5Aclose(attr_1a_id);
+        (void)H5Aclose(attr_2_id);
+        (void)H5Aclose(attr_2a_id);
+        (void)H5Aclose(attr_3_id);
+        (void)H5Aclose(attr_3a_id);
+        (void)H5Fclose(file_id);
+    } H5E_END_TRY;
+    return FAIL;
+} /* test_minimized_dset_ohdr_attribute_addition */
+
+/*
+ * Compare header sizes against when headers have been minimized.
+ * Repeats tests with headers "compact" and normal.
+ */
+static herr_t
+test_minimized_dset_ohdr_size_comparisons(hid_t fapl_id)
+{
+    hsize_t  array_10[1] = {10}; /* dataspace extents */
+    unsigned compact     = 0;
+
+    /* IDs that are file-agnostic */
+    hid_t dspace_id     = -1;
+    hid_t int_type_id   = -1;
+    hid_t dcpl_minimize = -1;
+    hid_t dcpl_dontmin  = -1;
+    hid_t dcpl_default  = -1;
+
+    /* IDs for non-minimized file open */
+    hid_t file_f_id   = -1; /* lower 'f' for standard file setting */
+    hid_t dset_f_x_id = -1; /* 'x' for default */
+    hid_t dset_f_N_id = -1; /* 'N' for explcit non-minimized dset */
+    hid_t dset_f_Y_id = -1; /* 'Y' for minimized dset */
+
+    /* IDs for minimized file open */
+    hid_t file_F_id   = -1; /* upper 'F' for minimized file setting */
+    hid_t dset_F_x_id = -1; /* 'x' for default */
+    hid_t dset_F_N_id = -1; /* 'N' for explcit non-minimized dset */
+    hid_t dset_F_Y_id = -1; /* 'Y' for minimized dset */
+
+    char filename_a[512] = "";
+    char filename_b[512] = "";
+
+    herr_t ret;
+
+    /* dataset suffixes:
+     *                | default | minimize | don't minimize (dcpl-set)
+     * ---------------+---------+----------+---------------
+     * file-default   |   f_x   |   f_Y    |   f_N
+     * ---------------+---------+----------+---------------
+     * file-minimized |   F_x   |   F_Y    |   F_N
+     */
+
+    TESTING("minimized dset object headers size comparisons");
+
+    /*********
+     * SETUP *
+     *********/
+
+    if(h5_fixname(FILENAME[1], fapl_id, filename_a, sizeof(filename_a)) == NULL)
+        TEST_ERROR
+
+    if(h5_fixname(FILENAME[2], fapl_id, filename_b, sizeof(filename_b)) == NULL)
+        TEST_ERROR
+
+    for (compact = 0; compact < 2; compact++) { /* 0 or 1 */
+        dcpl_default = H5Pcreate(H5P_DATASET_CREATE);
+        if(dcpl_default < 0) TEST_ERROR
+
+        dcpl_minimize = H5Pcreate(H5P_DATASET_CREATE);
+        if(dcpl_minimize < 0) TEST_ERROR
+        ret = H5Pset_dset_no_attrs_hint(dcpl_minimize, TRUE);
+        if(ret < 0) TEST_ERROR
+
+        dcpl_dontmin = H5Pcreate(H5P_DATASET_CREATE);
+        if(dcpl_dontmin < 0) TEST_ERROR
+        ret = H5Pset_dset_no_attrs_hint(dcpl_dontmin, FALSE);
+        if(ret < 0) TEST_ERROR
+
+        if(compact) {
+            HDprintf("...compact ");
+            ret = H5Pset_layout(dcpl_default, H5D_COMPACT);
+            if(ret < 0) TEST_ERROR
+            ret = H5Pset_layout(dcpl_minimize, H5D_COMPACT);
+            if(ret < 0) TEST_ERROR
+            ret = H5Pset_layout(dcpl_dontmin, H5D_COMPACT);
+            if(ret < 0) TEST_ERROR
+        } else
+            HDprintf("...not compact ");
+
+        dspace_id = H5Screate_simple(1, array_10, NULL);
+        if(dspace_id < 0) TEST_ERROR
+
+        int_type_id = H5Tcopy(H5T_NATIVE_INT);
+        if(int_type_id < 0) TEST_ERROR
+
+        file_f_id = H5Fcreate(filename_a, H5F_ACC_TRUNC, H5P_DEFAULT, fapl_id);
+        if(file_f_id < 0) TEST_ERROR
+
+        dset_f_x_id = H5Dcreate2(file_f_id, "default", int_type_id, dspace_id, H5P_DEFAULT, dcpl_default, H5P_DEFAULT);
+        if(dset_f_x_id < 0) TEST_ERROR
+
+        dset_f_N_id = H5Dcreate2(file_f_id, "dsetNOT", int_type_id, dspace_id, H5P_DEFAULT, dcpl_dontmin, H5P_DEFAULT);
+        if(dset_f_N_id < 0) TEST_ERROR
+
+        dset_f_Y_id = H5Dcreate2(file_f_id, "dsetMIN", int_type_id, dspace_id, H5P_DEFAULT, dcpl_minimize, H5P_DEFAULT);
+        if(dset_f_x_id < 0) TEST_ERROR
+
+        file_F_id = H5Fcreate(filename_b, H5F_ACC_TRUNC, H5P_DEFAULT, fapl_id);
+        if(file_F_id < 0) TEST_ERROR
+        ret = H5Fset_dset_no_attrs_hint(file_F_id, TRUE);
+        if(ret < 0) TEST_ERROR
+
+        dset_F_x_id = H5Dcreate2(file_F_id, "default", int_type_id, dspace_id, H5P_DEFAULT, dcpl_default, H5P_DEFAULT);
+        if(dset_F_x_id < 0) TEST_ERROR
+
+        dset_F_N_id = H5Dcreate2(file_F_id, "dsetNOT", int_type_id, dspace_id, H5P_DEFAULT, dcpl_dontmin, H5P_DEFAULT);
+        if(dset_F_N_id < 0) TEST_ERROR
+
+        dset_F_Y_id = H5Dcreate2(file_F_id, "dsetMIN", int_type_id, dspace_id, H5P_DEFAULT, dcpl_minimize, H5P_DEFAULT);
+        if(dset_F_Y_id < 0) TEST_ERROR
+
+        /*********
+         * TESTS *
+         *********/
+
+        if(oh_compare(dset_f_x_id, dset_f_x_id) != EQ) TEST_ERROR /* identity */
+
+        if(oh_compare(dset_f_x_id, dset_f_N_id) != EQ) TEST_ERROR
+        if(oh_compare(dset_f_x_id, dset_f_Y_id) != GT) TEST_ERROR
+        if(oh_compare(dset_f_N_id, dset_f_Y_id) != GT) TEST_ERROR
+
+        if(oh_compare(dset_F_x_id, dset_F_N_id) != EQ) TEST_ERROR
+        if(oh_compare(dset_F_x_id, dset_F_Y_id) != EQ) TEST_ERROR
+        if(oh_compare(dset_F_N_id, dset_F_Y_id) != EQ) TEST_ERROR
+
+        if(oh_compare(dset_F_x_id, dset_f_Y_id) != EQ) TEST_ERROR
+        if(oh_compare(dset_F_x_id, dset_f_x_id) != LT) TEST_ERROR
+
+        /************
+         * TEARDOWN *
+         ************/
+
+        if(H5Sclose(dspace_id) < 0) TEST_ERROR
+        if(H5Tclose(int_type_id) < 0) TEST_ERROR
+        if(H5Pclose(dcpl_default) < 0) TEST_ERROR
+        if(H5Pclose(dcpl_minimize) < 0) TEST_ERROR
+        if(H5Pclose(dcpl_dontmin) < 0) TEST_ERROR
+
+        if(H5Fclose(file_f_id) < 0) TEST_ERROR
+        if(H5Dclose(dset_f_x_id) < 0) TEST_ERROR
+        if(H5Dclose(dset_f_N_id) < 0) TEST_ERROR
+        if(H5Dclose(dset_f_Y_id) < 0) TEST_ERROR
+
+        if(H5Fclose(file_F_id) < 0) TEST_ERROR
+        if(H5Dclose(dset_F_x_id) < 0) TEST_ERROR
+        if(H5Dclose(dset_F_N_id) < 0) TEST_ERROR
+        if(H5Dclose(dset_F_Y_id) < 0) TEST_ERROR
+
+    } /* compact and non-compact */
+
+    PASSED()
+    return SUCCEED;
+
+error :
+    H5E_BEGIN_TRY {
+        (void)H5Pclose(dcpl_default);
+        (void)H5Pclose(dcpl_minimize);
+        (void)H5Pclose(dcpl_dontmin);
+        (void)H5Sclose(dspace_id);
+        (void)H5Tclose(int_type_id);
+
+        (void)H5Fclose(file_f_id);
+        (void)H5Dclose(dset_f_x_id);
+        (void)H5Dclose(dset_f_N_id);
+        (void)H5Dclose(dset_f_Y_id);
+
+        (void)H5Fclose(file_F_id);
+        (void)H5Dclose(dset_F_x_id);
+        (void)H5Dclose(dset_F_N_id);
+        (void)H5Dclose(dset_F_Y_id);
+    } H5E_END_TRY;
+    return FAIL;
+} /* test_minimized_dset_ohdr_size_comparisons */
+
+/*
+ * Test minimized dataset object header with filter/pipeline message
+ */
+static herr_t
+test_minimized_dset_ohdr_with_filter(hid_t fapl_id)
+{
+    char           filename[512]   = "";
+    const hsize_t  extents[1]      = {1024}; /* extents of dataspace */
+    const unsigned filter_values[] = {0};  /* TBD */
+    const hsize_t  chunk_dim[]     = {32};  /* needed for filter */
+    const int      ndims           = 1;
+    hid_t          dspace_id       = -1;
+    hid_t          dtype_id        = -1;
+    hid_t          dcpl_xZ_id      = -1;
+    hid_t          dcpl_mx_id      = -1;
+    hid_t          dcpl_mZ_id      = -1;
+    hid_t          dset_xx_id      = -1;
+    hid_t          dset_xZ_id      = -1;
+    hid_t          dset_mx_id      = -1;
+    hid_t          dset_mZ_id      = -1;
+    hid_t          file_id         = -1;
+    herr_t         ret;
+
+    /* dcpl suffixes:
+     *           | default | minimize
+     * ----------+---------+---------
+     * no filter |    xx   |   mx
+     * ----------+---------+---------
+     * filter    |    xZ   |   mZ
+     */
+
+    TESTING("minimized dset object headers with filter message");
+
+    /*********
+     * SETUP *
+     *********/
+
+    if(h5_fixname(FILENAME[1], fapl_id, filename, sizeof(filename)) == NULL)
+        TEST_ERROR
+
+    dcpl_mx_id = H5Pcreate(H5P_DATASET_CREATE);
+    if(dcpl_mx_id < 0) TEST_ERROR
+    ret = H5Pset_dset_no_attrs_hint(dcpl_mx_id, TRUE);
+    if(ret < 0) TEST_ERROR
+
+    dcpl_xZ_id = H5Pcreate(H5P_DATASET_CREATE);
+    if(dcpl_xZ_id < 0) TEST_ERROR
+    ret = H5Pset_chunk(dcpl_xZ_id, ndims, chunk_dim);
+    if(ret < 0) TEST_ERROR
+    ret = H5Pset_filter(dcpl_xZ_id, H5Z_FILTER_DEFLATE, H5Z_FLAG_OPTIONAL, 0, filter_values);
+    if(ret < 0) TEST_ERROR
+    dcpl_mZ_id = H5Pcreate(H5P_DATASET_CREATE);
+    if(dcpl_mZ_id < 0) TEST_ERROR
+    ret = H5Pset_dset_no_attrs_hint(dcpl_mZ_id, TRUE);
+    if(ret < 0) TEST_ERROR
+    ret = H5Pset_chunk(dcpl_mZ_id, ndims, chunk_dim);
+    if(ret < 0) TEST_ERROR
+    ret = H5Pset_filter( dcpl_mZ_id, H5Z_FILTER_DEFLATE, H5Z_FLAG_OPTIONAL, 0, filter_values);
+    if(ret < 0) TEST_ERROR
+
+    dspace_id = H5Screate_simple(1, extents, extents);
+    if(dspace_id < 0) TEST_ERROR
+
+    dtype_id = H5Tcopy(H5T_NATIVE_INT);
+    if(dtype_id < 0) TEST_ERROR
+
+    file_id = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl_id);
+    if(file_id < 0) TEST_ERROR
+
+    dset_xx_id = H5Dcreate2(file_id, "xx", dtype_id, dspace_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    if(dset_xx_id < 0) TEST_ERROR
+
+    dset_mx_id = H5Dcreate2(file_id, "Mx", dtype_id, dspace_id, H5P_DEFAULT, dcpl_mx_id, H5P_DEFAULT);
+    if(dset_mx_id < 0) TEST_ERROR
+
+    dset_xZ_id = H5Dcreate2(file_id, "xZ", dtype_id, dspace_id, H5P_DEFAULT, dcpl_xZ_id, H5P_DEFAULT);
+    if(dset_xZ_id < 0) TEST_ERROR
+
+    dset_mZ_id = H5Dcreate2(file_id, "MZ", dtype_id, dspace_id, H5P_DEFAULT, dcpl_mZ_id, H5P_DEFAULT);
+    if(dset_mZ_id < 0) TEST_ERROR
+
+    /*********
+     * TESTS *
+     *********/
+
+    if(oh_compare(dset_mx_id, dset_xx_id) != LT) TEST_ERROR
+    if(oh_compare(dset_mx_id, dset_xZ_id) != LT) TEST_ERROR
+    if(oh_compare(dset_mZ_id, dset_mx_id) != GT) TEST_ERROR
+    if(oh_compare(dset_mZ_id, dset_xZ_id) != LT) TEST_ERROR
+
+    /************
+     * TEARDOWN *
+     ************/
+
+    if(H5Sclose(dspace_id) < 0) TEST_ERROR
+    if(H5Tclose(dtype_id) < 0) TEST_ERROR
+    if(H5Pclose(dcpl_xZ_id) < 0) TEST_ERROR
+    if(H5Pclose(dcpl_mx_id) < 0) TEST_ERROR
+    if(H5Pclose(dcpl_mZ_id) < 0) TEST_ERROR
+    if(H5Dclose(dset_xx_id) < 0) TEST_ERROR
+    if(H5Dclose(dset_xZ_id) < 0) TEST_ERROR
+    if(H5Dclose(dset_mx_id) < 0) TEST_ERROR
+    if(H5Dclose(dset_mZ_id) < 0) TEST_ERROR
+    if(H5Fclose(file_id) < 0) TEST_ERROR
+
+    PASSED()
+    return SUCCEED;
+
+error:
+    H5E_BEGIN_TRY {
+        (void)H5Sclose(dspace_id);
+        (void)H5Tclose(dtype_id);
+        (void)H5Pclose(dcpl_xZ_id);
+        (void)H5Pclose(dcpl_mx_id);
+        (void)H5Pclose(dcpl_mZ_id);
+        (void)H5Dclose(dset_xx_id);
+        (void)H5Dclose(dset_xZ_id);
+        (void)H5Dclose(dset_mx_id);
+        (void)H5Dclose(dset_mZ_id);
+        (void)H5Fclose(file_id);
+    } H5E_END_TRY;
+    return FAIL;
+} /* test_minimized_dset_ohdr_with_filter */
+
+/*
+ * Test minimized dataset object header and recording modification times.
+ */
+static herr_t
+test_minimized_dset_ohdr_modification_times(hid_t _fapl_id)
+{
+    /* test-local structure for parameterized testing
+     */
+    struct testcase {
+        unsigned oh_version;
+    };
+
+    char          filename[512] = "";
+    const hsize_t extents[1]    = {128}; /* extents of dataspace */
+    hid_t         dspace_id     = -1;
+    hid_t         dtype_id      = -1;
+    hid_t         dcpl_xT_id    = -1; /* Track modtime */
+    hid_t         dcpl_mx_id    = -1; /* minimized */
+    hid_t         dcpl_mT_id    = -1; /* minimized, Track */
+    hid_t         dcpl_mN_id    = -1; /* minimized, do Not track */
+    hid_t         dset_xx_id    = -1;
+    hid_t         dset_xT_id    = -1;
+    hid_t         dset_mx_id    = -1;
+    hid_t         dset_mT_id    = -1;
+    hid_t         dset_mN_id    = -1;
+    hid_t         file_id       = -1;
+    hid_t         fapl_id       = -1;
+    herr_t        ret;
+
+    unsigned i       = 0; /* for testcase loop */
+    unsigned n_cases = 2; /* must match `cases` array size below */
+    struct testcase cases[2] = {
+        { 1, }, /* version 1 object header */
+        { 2, }, /* version 2 object header */
+    };
+
+    /* dcpl suffixes:
+     *             | default | minimize
+     * ------------+---------+---------
+     * default     |    xx   |   mx
+     * ------------+---------+---------
+     * don't track |    xN   |   mN
+     * ------------+---------+---------
+     * track       |    xT   |   mT
+     */
+
+    TESTING("minimized dset object headers with modification times");
+
+    /*********
+     * SETUP *
+     *********/
+
+    if(h5_fixname(FILENAME[1], _fapl_id, filename, sizeof(filename)) == NULL)
+        TEST_ERROR
+
+    dcpl_mx_id = H5Pcreate(H5P_DATASET_CREATE);
+    if(dcpl_mx_id < 0) TEST_ERROR
+    ret = H5Pset_dset_no_attrs_hint(dcpl_mx_id, TRUE);
+    if(ret < 0) TEST_ERROR
+
+    dcpl_xT_id = H5Pcreate(H5P_DATASET_CREATE);
+    if(dcpl_xT_id < 0) TEST_ERROR
+    ret = H5Pset_obj_track_times(dcpl_xT_id, TRUE);
+    if(ret < 0) TEST_ERROR
+
+    dcpl_mT_id = H5Pcreate(H5P_DATASET_CREATE);
+    if(dcpl_mT_id < 0) TEST_ERROR
+    ret = H5Pset_dset_no_attrs_hint(dcpl_mT_id, TRUE);
+    if(ret < 0) TEST_ERROR
+    ret = H5Pset_obj_track_times(dcpl_mT_id, TRUE);
+    if(ret < 0) TEST_ERROR
+
+    dcpl_mN_id = H5Pcreate(H5P_DATASET_CREATE);
+    if(dcpl_mN_id < 0) TEST_ERROR
+    ret = H5Pset_dset_no_attrs_hint(dcpl_mN_id, TRUE);
+    if(ret < 0) TEST_ERROR
+    ret = H5Pset_obj_track_times(dcpl_mN_id, FALSE);
+    if(ret < 0) TEST_ERROR
+
+    dspace_id = H5Screate_simple(1, extents, extents);
+    if(dspace_id < 0) TEST_ERROR
+
+    dtype_id = H5Tcopy(H5T_NATIVE_INT);
+    if(dtype_id < 0) TEST_ERROR
+
+    for (i = 0; i < n_cases; i++) {
+
+        /* -------------- *
+         * per-case setup *
+         * -------------- */
+
+        if(cases[i].oh_version > 1) {
+            fapl_id = H5Pcreate(H5P_FILE_ACCESS);
+            if(fapl_id < 0) TEST_ERROR
+            ret = H5Pset_libver_bounds(fapl_id, H5F_LIBVER_V18, H5F_LIBVER_V110);
+            if(ret < 0) TEST_ERROR
+        } else {
+            fapl_id = H5Pcopy(_fapl_id);
+            if(fapl_id < 0) TEST_ERROR
+        }
+
+        file_id = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl_id);
+        if(file_id < 0) TEST_ERROR
+
+        dset_xx_id = H5Dcreate2( file_id, "xx", dtype_id, dspace_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+        if(dset_xx_id < 0) TEST_ERROR
+
+        dset_mx_id = H5Dcreate2(file_id, "mx", dtype_id, dspace_id, H5P_DEFAULT, dcpl_mx_id, H5P_DEFAULT);
+        if(dset_mx_id < 0) TEST_ERROR
+
+        dset_xT_id = H5Dcreate2(file_id, "xT", dtype_id, dspace_id, H5P_DEFAULT, dcpl_xT_id, H5P_DEFAULT);
+        if(dset_xT_id < 0) TEST_ERROR
+        dset_mT_id = H5Dcreate2(file_id, "mT", dtype_id, dspace_id, H5P_DEFAULT, dcpl_mT_id, H5P_DEFAULT);
+        if(dset_mT_id < 0) TEST_ERROR
+
+        dset_mN_id = H5Dcreate2(file_id, "mN", dtype_id, dspace_id, H5P_DEFAULT, dcpl_mN_id, H5P_DEFAULT);
+        if(dset_mN_id < 0) TEST_ERROR
+
+        /* ----- *
+         * TESTS *
+         * ----- */
+
+        /* sanity check */
+        if(oh_compare(dset_mx_id, dset_xx_id) != LT) TEST_ERROR
+        if(oh_compare(dset_mx_id, dset_xT_id) != LT) TEST_ERROR
+
+        if(oh_compare(dset_xx_id, dset_xT_id) != EQ) TEST_ERROR
+        if(oh_compare(dset_mx_id, dset_mT_id) != EQ) TEST_ERROR
+        if(oh_compare(dset_mN_id, dset_mT_id) != LT) TEST_ERROR
+
+        if(oh_compare(dset_mT_id, dset_xT_id) != LT) TEST_ERROR
+
+        /* ----------------- *
+         * per-case teardown *
+         * ----------------- */
+
+        if(H5Dclose(dset_xx_id) < 0) TEST_ERROR
+        if(H5Dclose(dset_xT_id) < 0) TEST_ERROR
+        if(H5Dclose(dset_mx_id) < 0) TEST_ERROR
+        if(H5Dclose(dset_mT_id) < 0) TEST_ERROR
+        if(H5Dclose(dset_mN_id) < 0) TEST_ERROR
+        if(H5Fclose(file_id) < 0) TEST_ERROR
+        if(H5Pclose(fapl_id) < 0) TEST_ERROR
+
+    } /* for each version tested */
+
+    /************
+     * TEARDOWN *
+     ************/
+
+    if(H5Sclose(dspace_id) < 0) TEST_ERROR
+    if(H5Tclose(dtype_id) < 0) TEST_ERROR
+    if(H5Pclose(dcpl_xT_id) < 0) TEST_ERROR
+    if(H5Pclose(dcpl_mx_id) < 0) TEST_ERROR
+    if(H5Pclose(dcpl_mT_id) < 0) TEST_ERROR
+    if(H5Pclose(dcpl_mN_id) < 0) TEST_ERROR
+
+    PASSED()
+    return SUCCEED;
+
+error:
+    H5E_BEGIN_TRY {
+        (void)H5Sclose(dspace_id);
+        (void)H5Tclose(dtype_id);
+        (void)H5Pclose(dcpl_xT_id);
+        (void)H5Pclose(dcpl_mx_id);
+        (void)H5Pclose(dcpl_mT_id);
+        (void)H5Pclose(dcpl_mN_id);
+        (void)H5Dclose(dset_xx_id);
+        (void)H5Dclose(dset_xT_id);
+        (void)H5Dclose(dset_mx_id);
+        (void)H5Dclose(dset_mT_id);
+        (void)H5Dclose(dset_mN_id);
+        (void)H5Fclose(file_id);
+        (void)H5Pclose(fapl_id);
+    } H5E_END_TRY;
+    return FAIL;
+} /* test_minimized_dset_ohdr_modification_times */
+
+/*
+ * Test minimized dataset object header with a fill value set.
+ */
+static herr_t
+test_minimized_dset_ohdr_fillvalue_backwards_compatability(hid_t _fapl_id)
+{
+    char          filename[512] = "";
+    const hsize_t extents[1]    = {64}; /* extents of dataspace */
+    const int     fill[1]       = {343}; /* fill value of dataset */
+    hid_t         file_id       = -1;
+    hid_t         dtype_id      = -1;
+    hid_t         dspace_id     = -1;
+    hid_t         dcpl_id       = -1;
+    hid_t         fapl_id       = -1;
+    hid_t         dset_0_id     = -1;
+    hid_t         dset_1_id     = -1;
+    herr_t        ret;
+
+    /*********
+     * SETUP *
+     *********/
+
+    TESTING("minimized dset object headers with fill values and different libver support");
+
+    if(h5_fixname(FILENAME[1], _fapl_id, filename, sizeof(filename)) == NULL)
+        TEST_ERROR
+
+    dspace_id = H5Screate_simple(1, extents, extents);
+    if(dspace_id < 0) TEST_ERROR
+
+    dtype_id = H5Tcopy(H5T_NATIVE_INT);
+    if(dtype_id < 0) TEST_ERROR
+
+    dcpl_id = H5Pcreate(H5P_DATASET_CREATE);
+    if(dcpl_id < 0) TEST_ERROR
+
+    ret = H5Pset_dset_no_attrs_hint(dcpl_id, TRUE);
+    if(ret == FAIL) TEST_ERROR;
+
+    ret = H5Pset_fill_value(dcpl_id, dtype_id, fill);
+    if(ret == FAIL) TEST_ERROR;
+
+    fapl_id = H5Pcopy(_fapl_id);
+    if(fapl_id < 0) TEST_ERROR
+
+    ret = H5Pset_libver_bounds(fapl_id, H5F_LIBVER_EARLIEST, H5F_LIBVER_LATEST);
+    if(ret == FAIL) TEST_ERROR;
+
+    file_id = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl_id);
+    if(file_id < 0) TEST_ERROR
+
+    dset_0_id = H5Dcreate2(file_id, "fullrange", dtype_id, dspace_id, H5P_DEFAULT, dcpl_id, H5P_DEFAULT);
+    if(dset_0_id < 0) TEST_ERROR
+
+    /* Close file and re-open with different libver bounds.
+     * Dataset "fullrange" must also be closed for expected reopen behavior.
+     */
+    if(H5Fclose(file_id) < 0) TEST_ERROR;
+    if(H5Dclose(dset_0_id) < 0) TEST_ERROR
+
+    ret = H5Pset_libver_bounds(fapl_id, H5F_LIBVER_V18, H5F_LIBVER_LATEST);
+    if(ret == FAIL) TEST_ERROR;
+
+    file_id = H5Fopen(filename, H5F_ACC_RDWR, fapl_id);
+    if(file_id < 0) TEST_ERROR
+
+    dset_1_id = H5Dcreate2(file_id, "upperrange", dtype_id, dspace_id, H5P_DEFAULT, dcpl_id, H5P_DEFAULT);
+    if(dset_1_id < 0) TEST_ERROR
+
+    /* re-open "fullrange" dataset
+     */
+     dset_0_id = H5Dopen2(file_id, "fullrange", H5P_DEFAULT);
+     if(dset_0_id < 0) TEST_ERROR
+
+    /*********
+     * TESTS *
+     *********/
+
+    /* dset not supporting pre-1.08 should be smaller? */
+    if(oh_compare(dset_1_id, dset_0_id) != LT) TEST_ERROR
+
+    /************
+     * TEARDOWN *
+     ************/
+
+    if(H5Sclose(dspace_id) < 0) TEST_ERROR
+    if(H5Tclose(dtype_id) < 0) TEST_ERROR
+    if(H5Pclose(dcpl_id) < 0) TEST_ERROR
+    if(H5Pclose(fapl_id) < 0) TEST_ERROR
+    if(H5Dclose(dset_0_id) < 0) TEST_ERROR
+    if(H5Dclose(dset_1_id) < 0) TEST_ERROR
+    if(H5Fclose(file_id) < 0) TEST_ERROR;
+
+    PASSED()
+    return SUCCEED;
+
+error:
+    H5E_BEGIN_TRY {
+        (void)H5Sclose(dspace_id);
+        (void)H5Tclose(dtype_id);
+        (void)H5Pclose(dcpl_id);
+        (void)H5Pclose(fapl_id);
+        (void)H5Dclose(dset_0_id);
+        (void)H5Dclose(dset_1_id);
+        (void)H5Fclose(file_id);
+    } H5E_END_TRY;
+    return FAIL;
+} /* test_minimized_dset_ohdr_fillvalue_backwards_compatability */
+
+/*
  *  Verify that messages are moved forward into a "continuation message":
  *    Create an object header with several continuation chunks
  *    Remove a message in the last chunk
@@ -513,6 +1399,16 @@ test_unknown(unsigned bogus_id, char *filename, hid_t fapl)
 
     PASSED();
 
+    TESTING("object with unknown header message & 'shareable' flag set");
+
+    /* Open the dataset with the unknown header message, adn "shareable" flag */
+    if((did = H5Dopen2(loc_bogus, "Dataset5", H5P_DEFAULT)) < 0)
+        FAIL_STACK_ERROR
+    if(H5Dclose(did) < 0)
+        FAIL_STACK_ERROR
+
+    PASSED();
+
     TESTING("object in r/o file with unknown header message & 'fail if unknown and open for write' flag set");
 
     /* Open the dataset with the unknown header message, and "fail if unknown and open for write" flag */
@@ -1033,6 +1929,21 @@ main(void)
         if(test_ohdr_cache(filename, fapl) < 0)
             TEST_ERROR
 
+        if(test_minimized_dset_ohdr_attribute_addition(fapl) < 0)
+            TEST_ERROR
+
+        if(test_minimized_dset_ohdr_size_comparisons(fapl) < 0)
+            TEST_ERROR
+
+        if(test_minimized_dset_ohdr_with_filter(fapl) < 0)
+            TEST_ERROR
+
+        if(test_minimized_dset_ohdr_modification_times(fapl) < 0)
+            TEST_ERROR
+
+        if(test_minimized_dset_ohdr_fillvalue_backwards_compatability(fapl) < 0)
+            TEST_ERROR
+
       } /* high */
     } /* low */
 
diff --git a/test/tattr.c b/test/tattr.c
index 4358d4c..9b6ae90 100644
--- a/test/tattr.c
+++ b/test/tattr.c
@@ -157,6 +157,12 @@ typedef struct {
 static herr_t attr_op1(hid_t loc_id, const char *name, const H5A_info_t *ainfo,
     void *op_data);
 
+/* Global dcpl ID, can be re-set as a generated dcpl for various operations
+ * across multiple tests.
+ * e.g., minimized dataset object headers
+ */
+static hid_t dcpl_g = H5P_DEFAULT;
+
 
 
 /****************************************************************
@@ -196,7 +202,7 @@ test_attr_basic_write(hid_t fapl)
     CHECK(sid1, FAIL, "H5Screate_simple");
 
     /* Create a dataset */
-    dataset = H5Dcreate2(fid1, DSET1_NAME, H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    dataset = H5Dcreate2(fid1, DSET1_NAME, H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(dataset, FAIL, "H5Dcreate2");
 
     /* Create dataspace for attribute */
@@ -516,7 +522,7 @@ test_attr_flush(hid_t fapl)
     spc = H5Screate(H5S_SCALAR);
     CHECK(spc, FAIL, "H5Screate");
 
-    set = H5Dcreate2(fil, DSET1_NAME, H5T_NATIVE_DOUBLE, spc, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    set = H5Dcreate2(fil, DSET1_NAME, H5T_NATIVE_DOUBLE, spc, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(set, FAIL, "H5Dcreate2");
 
     att = H5Acreate2(set, ATTR1_NAME, H5T_NATIVE_DOUBLE, spc, H5P_DEFAULT, H5P_DEFAULT);
@@ -587,7 +593,7 @@ test_attr_plist(hid_t fapl)
     CHECK(sid1, FAIL, "H5Screate_simple");
 
     /* Create a dataset */
-    dataset = H5Dcreate2(fid1, DSET1_NAME, H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    dataset = H5Dcreate2(fid1, DSET1_NAME, H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(dataset, FAIL, "H5Dcreate2");
 
     /* Create dataspace for attribute */
@@ -701,7 +707,7 @@ test_attr_compound_write(hid_t fapl)
     CHECK(sid1, FAIL, "H5Screate_simple");
 
     /* Create a dataset */
-    dataset = H5Dcreate2(fid1, DSET1_NAME, H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    dataset = H5Dcreate2(fid1, DSET1_NAME, H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(dataset, FAIL, "H5Dcreate2");
 
     /* Close dataset's dataspace */
@@ -937,7 +943,7 @@ test_attr_scalar_write(hid_t fapl)
     CHECK(sid1, FAIL, "H5Screate_simple");
 
     /* Create a dataset */
-    dataset = H5Dcreate2(fid1, DSET1_NAME, H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    dataset = H5Dcreate2(fid1, DSET1_NAME, H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(dataset, FAIL, "H5Dcreate2");
 
     /* Create dataspace for attribute */
@@ -1078,7 +1084,7 @@ test_attr_mult_write(hid_t fapl)
     CHECK(sid1, FAIL, "H5Screate_simple");
 
     /* Create a dataset */
-    dataset = H5Dcreate2(fid1, DSET1_NAME, H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    dataset = H5Dcreate2(fid1, DSET1_NAME, H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(dataset, FAIL, "H5Dcreate2");
 
     /* Close dataset's dataspace */
@@ -1456,7 +1462,7 @@ test_attr_iterate(hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Create a new dataset */
-    dataset = H5Dcreate2(file, DSET2_NAME, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    dataset = H5Dcreate2(file, DSET2_NAME, H5T_NATIVE_INT, sid, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(dataset, FAIL, "H5Dcreate2");
 
     /* Close dataspace */
@@ -1681,7 +1687,7 @@ test_attr_dtype_shared(hid_t fapl)
     CHECK(space_id, FAIL, "H5Screate");
 
     /* Create dataset */
-    dset_id = H5Dcreate2(file_id, DSET1_NAME, type_id, space_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    dset_id = H5Dcreate2(file_id, DSET1_NAME, type_id, space_id, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(dset_id, FAIL, "H5Dcreate2");
 
     /* Check reference count on named datatype */
@@ -1835,7 +1841,7 @@ test_attr_duplicate_ids(hid_t fapl)
 
     /* Create a dataset */
     dataset = H5Dcreate2(fid1, DSET1_NAME, H5T_NATIVE_UCHAR, sid1, H5P_DEFAULT,
-            H5P_DEFAULT, H5P_DEFAULT);
+            dcpl_g, H5P_DEFAULT);
     CHECK(dataset, FAIL, "H5Dcreate2");
 
     /* Create dataspace for attribute */
@@ -2161,7 +2167,7 @@ test_attr_dense_create(hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Query the group creation properties */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Create a dataset */
@@ -2292,7 +2298,7 @@ test_attr_dense_open(hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Query the group creation properties */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Enable creation order tracking on attributes, so creation order tests work */
@@ -2405,14 +2411,27 @@ test_attr_dense_delete(hid_t fcpl, hid_t fapl)
     h5_stat_size_t empty_filesize;       /* Size of empty file */
     h5_stat_size_t filesize;             /* Size of file after modifications */
     H5O_info_t  oinfo;          /* Object info                  */
+    int         use_min_dset_oh = (dcpl_g != H5P_DEFAULT);
     herr_t      ret;            /* Generic return value        */
 
     /* Output message about test being performed */
     MESSAGE(5, ("Testing Deleting Attributes in Dense Storage\n"));
 
     /* Create file */
+    if (use_min_dset_oh) { /* using minimized dataset headers */
+        /* modify fcpl...
+         * sidestep "bug" where file space is lost with minimized dset ohdrs
+         */
+        fcpl = H5Pcopy(fcpl);
+        CHECK(fcpl, FAIL, "H5Pcopy");
+        ret = H5Pset_file_space_strategy(fcpl, H5F_FSPACE_STRATEGY_FSM_AGGR, TRUE, 1);
+        CHECK(ret, FAIL, "H5Pset_file_space_strategy");
+    }
     fid = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl, fapl);
     CHECK(fid, FAIL, "H5Fcreate");
+    if (use_min_dset_oh)
+        CHECK(H5Pclose(fcpl), FAIL, "H5Pclose");
+
 
     /* Close file */
     ret = H5Fclose(fid);
@@ -2432,7 +2451,7 @@ test_attr_dense_delete(hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Query the group creation properties */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (use_min_dset_oh) ? H5Pcopy(dcpl_g) : H5Pcreate(H5P_DATASET_CREATE);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Enable creation order tracking on attributes, so creation order tests work */
@@ -2584,14 +2603,26 @@ test_attr_dense_rename(hid_t fcpl, hid_t fapl)
     h5_stat_size_t filesize;             /* Size of file after modifications */
     H5O_info_t  oinfo;          /* Object info */
     unsigned    u;              /* Local index variable */
+    int         use_min_dset_oh = (dcpl_g != H5P_DEFAULT);
     herr_t      ret;            /* Generic return value        */
 
     /* Output message about test being performed */
     MESSAGE(5, ("Testing Renaming Attributes in Dense Storage\n"));
 
     /* Create file */
+    if (use_min_dset_oh) { /* using minimized dataset headers */
+        /* modify fcpl...
+         * sidestep "bug" where file space is lost with minimized dset ohdrs
+         */
+        fcpl = H5Pcopy(fcpl);
+        CHECK(fcpl, FAIL, "H5Pcopy");
+        ret = H5Pset_file_space_strategy(fcpl, H5F_FSPACE_STRATEGY_FSM_AGGR, TRUE, 1);
+        CHECK(ret, FAIL, "H5Pset_file_space_strategy");
+    }
     fid = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl, fapl);
     CHECK(fid, FAIL, "H5Fcreate");
+    if (use_min_dset_oh)
+        CHECK(H5Pclose(fcpl), FAIL, "H5Pclose");
 
     /* Close file */
     ret = H5Fclose(fid);
@@ -2611,7 +2642,7 @@ test_attr_dense_rename(hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Query the group creation properties */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (use_min_dset_oh) ? H5Pcopy(dcpl_g) : H5Pcreate(H5P_DATASET_CREATE);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Create a dataset */
@@ -2743,14 +2774,26 @@ test_attr_dense_unlink(hid_t fcpl, hid_t fapl)
     h5_stat_size_t filesize;             /* Size of file after modifications */
     H5O_info_t  oinfo;          /* Object info */
     unsigned    u;              /* Local index variable */
+    int         use_min_dset_oh = (dcpl_g != H5P_DEFAULT);
     herr_t      ret;            /* Generic return value        */
 
     /* Output message about test being performed */
     MESSAGE(5, ("Testing Unlinking Object with Attributes in Dense Storage\n"));
 
     /* Create file */
-    fid = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl, fapl);
-    CHECK(fid, FAIL, "H5Fcreate");
+    if (use_min_dset_oh) { /* using minimized dataset headers */
+        /* modify fcpl...
+         * sidestep "bug" where file space is lost with minimized dset ohdrs
+         */
+        fcpl = H5Pcopy(fcpl);
+        CHECK(fcpl, FAIL, "H5Pcopy");
+        ret = H5Pset_file_space_strategy(fcpl, H5F_FSPACE_STRATEGY_FSM_AGGR, TRUE, 1);
+        CHECK(ret, FAIL, "H5Pset_file_space_strategy");
+    }
+     fid = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl, fapl);
+     CHECK(fid, FAIL, "H5Fcreate");
+    if (use_min_dset_oh)
+        CHECK(H5Pclose(fcpl), FAIL, "H5Pclose");
 
     /* Close file */
     ret = H5Fclose(fid);
@@ -2770,7 +2813,7 @@ test_attr_dense_unlink(hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Query the group creation properties */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (use_min_dset_oh) ? H5Pcopy(dcpl_g) : H5Pcreate(H5P_DATASET_CREATE);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Create a dataset */
@@ -2898,7 +2941,7 @@ test_attr_dense_limits(hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Query the group creation properties */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Change limits on compact/dense attribute storage */
@@ -3065,7 +3108,7 @@ test_attr_dense_dup_ids(hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Query the group creation properties */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Create a dataset */
@@ -3595,7 +3638,7 @@ test_attr_big(hid_t fcpl, hid_t fapl)
     CHECK(big_sid, FAIL, "H5Screate_simple");
 
     /* Query the group creation properties */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Retrieve limits for compact/dense attribute storage */
@@ -3861,7 +3904,7 @@ test_attr_null_space(hid_t fcpl, hid_t fapl)
     CHECK(null_sid, FAIL, "H5Screate");
 
     /* Create a dataset */
-    dataset = H5Dcreate2(fid, DSET1_NAME, H5T_NATIVE_UCHAR, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    dataset = H5Dcreate2(fid, DSET1_NAME, H5T_NATIVE_UCHAR, sid, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(dataset, FAIL, "H5Dcreate2");
 
 
@@ -4054,7 +4097,7 @@ test_attr_deprec(hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Create a dataset */
-    dataset = H5Dcreate2(fid, DSET1_NAME, H5T_NATIVE_UCHAR, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    dataset = H5Dcreate2(fid, DSET1_NAME, H5T_NATIVE_UCHAR, sid, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(dataset, FAIL, "H5Dcreate2");
 
 
@@ -4290,7 +4333,7 @@ test_attr_corder_create_basic(hid_t fcpl, hid_t fapl)
     CHECK(fid, FAIL, "H5Fcreate");
 
     /* Create dataset creation property list */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Get creation order indexing on object */
@@ -4413,7 +4456,7 @@ test_attr_corder_create_compact(hid_t fcpl, hid_t fapl)
     CHECK(fid, FAIL, "H5Fcreate");
 
     /* Create dataset creation property list */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Set attribute creation order tracking & indexing for object */
@@ -4613,7 +4656,7 @@ test_attr_corder_create_dense(hid_t fcpl, hid_t fapl)
     CHECK(fid, FAIL, "H5Fcreate");
 
     /* Create dataset creation property list */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Set attribute creation order tracking & indexing for object */
@@ -4948,7 +4991,7 @@ test_attr_corder_transition(hid_t fcpl, hid_t fapl)
     CHECK(fid, FAIL, "H5Fcreate");
 
     /* Create dataset creation property list */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Set attribute creation order tracking & indexing for object */
@@ -5359,7 +5402,7 @@ test_attr_corder_delete(hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Create dataset creation property list */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Set attribute creation order tracking & indexing for object */
@@ -5702,7 +5745,7 @@ test_attr_info_by_idx(hbool_t new_format, hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Create dataset creation property list */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Query the attribute creation properties */
@@ -5914,7 +5957,7 @@ test_attr_delete_by_idx(hbool_t new_format, hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Create dataset creation property list */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Query the attribute creation properties */
@@ -6857,7 +6900,7 @@ test_attr_iterate2(hbool_t new_format, hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Create dataset creation property list */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Query the attribute creation properties */
@@ -7218,7 +7261,7 @@ test_attr_open_by_idx(hbool_t new_format, hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Create dataset creation property list */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Query the attribute creation properties */
@@ -7565,7 +7608,7 @@ test_attr_open_by_name(hbool_t new_format, hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Create dataset creation property list */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Query the attribute creation properties */
@@ -7819,7 +7862,7 @@ test_attr_create_by_name(hbool_t new_format, hid_t fcpl, hid_t fapl)
     CHECK(sid, FAIL, "H5Screate");
 
     /* Create dataset creation property list */
-    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
     CHECK(dcpl, FAIL, "H5Pcreate");
 
     /* Query the attribute creation properties */
@@ -8120,7 +8163,7 @@ test_attr_shared_write(hid_t fcpl, hid_t fapl)
         } /* end if */
 
         /* Set up to query the object creation properties */
-        dcpl = H5Pcreate(H5P_DATASET_CREATE);
+        dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
         CHECK(dcpl, FAIL, "H5Pcreate");
 
         /* Create datasets */
@@ -8451,7 +8494,7 @@ test_attr_shared_rename(hid_t fcpl, hid_t fapl)
         } /* end if */
 
         /* Set up to query the object creation properties */
-        dcpl = H5Pcreate(H5P_DATASET_CREATE);
+        dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
         CHECK(dcpl, FAIL, "H5Pcreate");
 
         /* Create datasets */
@@ -8897,7 +8940,7 @@ test_attr_shared_delete(hid_t fcpl, hid_t fapl)
         } /* end if */
 
         /* Set up to query the object creation properties */
-        dcpl = H5Pcreate(H5P_DATASET_CREATE);
+        dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
         CHECK(dcpl, FAIL, "H5Pcreate");
 
         /* Create datasets */
@@ -9266,7 +9309,7 @@ test_attr_shared_unlink(hid_t fcpl, hid_t fapl)
         } /* end if */
 
         /* Set up to query the object creation properties */
-        dcpl = H5Pcreate(H5P_DATASET_CREATE);
+        dcpl = (dcpl_g == H5P_DEFAULT) ? H5Pcreate(H5P_DATASET_CREATE) : H5Pcopy(dcpl_g);
         CHECK(dcpl, FAIL, "H5Pcreate");
 
         /* Create datasets */
@@ -9858,7 +9901,7 @@ test_attr_bug3(hid_t fcpl, hid_t fapl)
     CHECK(ret, FAIL, "H5Tcommit2");
 
     /* Create dataset */
-    did = H5Dcreate2(fid, "dset", tid2, sid2, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    did = H5Dcreate2(fid, "dset", tid2, sid2, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(did, FAIL, "H5Dcreate2");
 
     /* Create attribute on datatype, using that datatype as its datatype */
@@ -9993,7 +10036,7 @@ test_attr_bug4(hid_t fcpl, hid_t fapl)
     CHECK(ret, FAIL, "H5Tcommit2");
 
     /* Create dataset */
-    did = H5Dcreate2(fid, "dset", tid, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    did = H5Dcreate2(fid, "dset", tid, sid, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(did, FAIL, "H5Dcreate2");
 
     /* Create attributes on group and dataset */
@@ -10075,7 +10118,7 @@ test_attr_bug5(hid_t fcpl, hid_t fapl)
     CHECK(ret, FAIL, "H5Tcommit2");
 
     /* Create dataset */
-    did1 = H5Dcreate2(fid1, BUG3_DSET_NAME, tid1, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    did1 = H5Dcreate2(fid1, BUG3_DSET_NAME, tid1, sid, H5P_DEFAULT, dcpl_g, H5P_DEFAULT);
     CHECK(did1, FAIL, "H5Dcreate2");
 
     /* Create attribute on root group */
@@ -10773,119 +10816,106 @@ test_attr(void)
 {
     hid_t    fapl = (-1), fapl2 = (-1);    /* File access property lists */
     hid_t    fcpl = (-1), fcpl2 = (-1);    /* File creation property lists */
+    hid_t    dcpl = -1;         /* Dataset creation property list */
     unsigned new_format;        /* Whether to use the new format or not */
     unsigned use_shared;        /* Whether to use shared attributes or not */
+    unsigned minimize_dset_oh;  /* Whether to use minimized dataset object headers */
     herr_t ret;                 /* Generic return value */
 
-    /* Output message about test being performed */
     MESSAGE(5, ("Testing Attributes\n"));
 
-    /* Create a default file access property list */
     fapl = H5Pcreate(H5P_FILE_ACCESS);
     CHECK(fapl, FAIL, "H5Pcreate");
 
-    /* Copy the file access property list */
+    /* fapl2 uses "latest version of the format" for creating objects in the file */
     fapl2 = H5Pcopy(fapl);
     CHECK(fapl2, FAIL, "H5Pcopy");
-
-    /* Set the "use the latest version of the format" bounds for creating objects in the file */
     ret = H5Pset_libver_bounds(fapl2, H5F_LIBVER_LATEST, H5F_LIBVER_LATEST);
     CHECK(ret, FAIL, "H5Pset_libver_bounds");
 
-    /* Create a default file creation property list */
     fcpl = H5Pcreate(H5P_FILE_CREATE);
     CHECK(fcpl, FAIL, "H5Pcreate");
 
-    /* Copy the file creation property list */
+    /* files with fcpl make all attributes (> 1 byte) shared
+     * i.e., all of them :-)
+     */
     fcpl2 = H5Pcopy(fcpl);
     CHECK(fcpl2, FAIL, "H5Pcopy");
-
-    /* Make attributes > 1 byte shared (i.e. all of them :-) */
     ret = H5Pset_shared_mesg_nindexes(fcpl2, (unsigned)1);
     CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
     ret = H5Pset_shared_mesg_index(fcpl2, (unsigned)0, H5O_SHMESG_ATTR_FLAG, (unsigned)1);
     CHECK_I(ret, "H5Pset_shared_mesg_index");
 
-    /* Loop over using new group format */
-    for(new_format = FALSE; new_format <= TRUE; new_format++) {
-        hid_t my_fapl;
-
-        /* Set the FAPL for the type of format */
-        if(new_format) {
-            MESSAGE(7, ("testing with new file format\n"));
-            my_fapl = fapl2;
-        } /* end if */
-        else {
-            MESSAGE(7, ("testing with old file format\n"));
-            my_fapl = fapl;
-        } /* end else */
+    for(minimize_dset_oh = 0; minimize_dset_oh <= 1; minimize_dset_oh++) {
+        if(minimize_dset_oh == 0) {
+            MESSAGE(7, ("testing with default dataset object headers\n"));
+            dcpl_g = H5P_DEFAULT;
+        } else {
+            MESSAGE(7, ("testing with minimzied dataset object headers\n"));
+            dcpl = H5Pcreate(H5P_DATASET_CREATE);
+            CHECK(dcpl, FAIL, "H5Pcreate");
+            ret = H5Pset_dset_no_attrs_hint(dcpl, TRUE);
+            CHECK_I(ret, "H5Pset_dset_no_attrs_hint");
+            dcpl_g = dcpl;
+        }
+
+        for(new_format = FALSE; new_format <= TRUE; new_format++) {
+            hid_t my_fapl;
+
+            /* Set the FAPL for the type of format */
+            if(new_format) {
+                MESSAGE(7, ("testing with new file format\n"));
+                my_fapl = fapl2;
+            } /* end if */
+            else {
+                MESSAGE(7, ("testing with old file format\n"));
+                my_fapl = fapl;
+            } /* end else */
 
-        /* These next two tests use the same file information */
-        test_attr_basic_write(my_fapl);    /* Test basic H5A writing code */
-        test_attr_basic_read(my_fapl);     /* Test basic H5A reading code */
+            /* These next two tests use the same file information */
+            test_attr_basic_write(my_fapl);    /* Test basic H5A writing code */
+            test_attr_basic_read(my_fapl);     /* Test basic H5A reading code */
 
-        /* These next two tests use their own file information */
-        test_attr_flush(my_fapl);          /* Test H5A I/O in the presence of H5Fflush calls */
-        test_attr_plist(my_fapl);          /* Test attribute property lists */
+            /* These next two tests use their own file information */
+            test_attr_flush(my_fapl);          /* Test H5A I/O in the presence of H5Fflush calls */
+            test_attr_plist(my_fapl);          /* Test attribute property lists */
 
-        /* These next two tests use the same file information */
-        test_attr_compound_write(my_fapl);  /* Test complex datatype H5A writing code */
-        test_attr_compound_read(my_fapl);   /* Test complex datatype H5A reading code */
+            /* These next two tests use the same file information */
+            test_attr_compound_write(my_fapl);  /* Test complex datatype H5A writing code */
+            test_attr_compound_read(my_fapl);   /* Test complex datatype H5A reading code */
 
-        /* These next two tests use the same file information */
-        test_attr_scalar_write(my_fapl);  /* Test scalar dataspace H5A writing code */
-        test_attr_scalar_read(my_fapl);   /* Test scalar dataspace H5A reading code */
+            /* These next two tests use the same file information */
+            test_attr_scalar_write(my_fapl);  /* Test scalar dataspace H5A writing code */
+            test_attr_scalar_read(my_fapl);   /* Test scalar dataspace H5A reading code */
 
-        /* These next four tests use the same file information */
-        test_attr_mult_write(my_fapl);     /* Test H5A writing code for multiple attributes */
-        test_attr_mult_read(my_fapl);      /* Test H5A reading code for multiple attributes */
-        test_attr_iterate(my_fapl);        /* Test H5A iterator code */
-        test_attr_delete(my_fapl);         /* Test H5A code for deleting attributes */
+            /* These next four tests use the same file information */
+            test_attr_mult_write(my_fapl);     /* Test H5A writing code for multiple attributes */
+            test_attr_mult_read(my_fapl);      /* Test H5A reading code for multiple attributes */
+            test_attr_iterate(my_fapl);        /* Test H5A iterator code */
+            test_attr_delete(my_fapl);         /* Test H5A code for deleting attributes */
 
-        /* This next test uses its own file information */
-        test_attr_dtype_shared(my_fapl);   /* Test using shared dataypes in attributes */
+            /* This next test uses its own file information */
+            test_attr_dtype_shared(my_fapl);   /* Test using shared dataypes in attributes */
 
-        /* This next test uses its own file information */
-        test_attr_duplicate_ids(my_fapl);
+            /* This next test uses its own file information */
+            test_attr_duplicate_ids(my_fapl);
 
-        /* Tests on "new format" attribute storage */
-        if(new_format == TRUE) {
-            /* Loop over using shared attributes */
             for(use_shared = FALSE; use_shared <= TRUE; use_shared++) {
                 hid_t my_fcpl;
 
-                /* Set the FCPL for shared or not */
-                if(use_shared) {
+                if(new_format == TRUE && use_shared) {
                     MESSAGE(7, ("testing with shared attributes\n"));
                     my_fcpl = fcpl2;
-                } /* end if */
-                else {
+                } else {
                     MESSAGE(7, ("testing without shared attributes\n"));
                     my_fcpl = fcpl;
-                } /* end else */
-
-                /* General attribute tests */
-                test_attr_dense_create(my_fcpl, my_fapl);       /* Test dense attribute storage creation */
-                test_attr_dense_open(my_fcpl, my_fapl);         /* Test opening attributes in dense storage */
-                test_attr_dense_delete(my_fcpl, my_fapl);       /* Test deleting attributes in dense storage */
-                test_attr_dense_rename(my_fcpl, my_fapl);       /* Test renaming attributes in dense storage */
-                test_attr_dense_unlink(my_fcpl, my_fapl);       /* Test unlinking object with attributes in dense storage */
-                test_attr_dense_limits(my_fcpl, my_fapl);       /* Test dense attribute storage limits */
-                test_attr_dense_dup_ids(my_fcpl, my_fapl);      /* Test duplicated IDs for dense attribute storage */
+                }
 
                 test_attr_big(my_fcpl, my_fapl);                /* Test storing big attribute */
                 test_attr_null_space(my_fcpl, my_fapl);         /* Test storing attribute with NULL dataspace */
                 test_attr_deprec(fcpl, my_fapl);                /* Test deprecated API routines */
                 test_attr_many(new_format, my_fcpl, my_fapl);               /* Test storing lots of attributes */
 
-                /* Attribute creation order tests */
-                test_attr_corder_create_basic(my_fcpl, my_fapl);/* Test creating an object w/attribute creation order info */
-                test_attr_corder_create_compact(my_fcpl, my_fapl);  /* Test compact attribute storage on an object w/attribute creation order info */
-                test_attr_corder_create_dense(my_fcpl, my_fapl);/* Test dense attribute storage on an object w/attribute creation order info */
-                test_attr_corder_create_reopen(my_fcpl, my_fapl);/* Test creating attributes w/reopening file from using new format to using old format */
-                test_attr_corder_transition(my_fcpl, my_fapl);  /* Test attribute storage transitions on an object w/attribute creation order info */
-                test_attr_corder_delete(my_fcpl, my_fapl);      /* Test deleting object using dense storage w/attribute creation order info */
-
                 /* New attribute API routine tests */
                 test_attr_info_by_idx(new_format, my_fcpl, my_fapl);    /* Test querying attribute info by index */
                 test_attr_delete_by_idx(new_format, my_fcpl, my_fapl);  /* Test deleting attribute by index */
@@ -10894,14 +10924,6 @@ test_attr(void)
                 test_attr_open_by_name(new_format, my_fcpl, my_fapl);   /* Test opening attributes by name */
                 test_attr_create_by_name(new_format, my_fcpl, my_fapl); /* Test creating attributes by name */
 
-                /* More complex tests with both "new format" and "shared" attributes */
-                if(use_shared == TRUE) {
-                    test_attr_shared_write(my_fcpl, my_fapl);   /* Test writing to shared attributes in compact & dense storage */
-                    test_attr_shared_rename(my_fcpl, my_fapl);  /* Test renaming shared attributes in compact & dense storage */
-                    test_attr_shared_delete(my_fcpl, my_fapl);  /* Test deleting shared attributes in compact & dense storage */
-                    test_attr_shared_unlink(my_fcpl, my_fapl);  /* Test unlinking object with shared attributes in compact & dense storage */
-                } /* end if */
-
                 /* Tests that address specific bugs */
                 test_attr_bug1(my_fcpl, my_fapl);               /* Test odd allocation operations */
                 test_attr_bug2(my_fcpl, my_fapl);               /* Test many deleted attributes */
@@ -10909,41 +10931,57 @@ test_attr(void)
                 test_attr_bug4(my_fcpl, my_fapl);               /* Test attributes on named datatypes */
                 test_attr_bug5(my_fcpl, my_fapl);               /* Test opening/closing attributes through different file handles */
                 test_attr_bug6(my_fcpl, my_fapl);               /* Test reading empty attribute */
-                test_attr_bug7(my_fcpl, my_fapl);               /* Test creating and deleting large attributes in ohdr chunk 0 */
+                /* test_attr_bug7 is specific to the "new" object header format,
+                 * and in fact fails if used with the old format due to the
+                 * attributes being larger than 64K */
                 test_attr_bug8(my_fcpl, my_fapl);               /* Test attribute expanding object header with undecoded messages */
                 test_attr_bug9(my_fcpl, my_fapl);               /* Test large attributes converting to dense storage */
-                test_attr_delete_last_dense(my_fcpl, my_fapl);  /* Test */
-            } /* end for */
-        } /* end if */
-        else {
-            /* General attribute tests */
-            test_attr_big(fcpl, my_fapl);                       /* Test storing big attribute */
-            test_attr_null_space(fcpl, my_fapl);                /* Test storing attribute with NULL dataspace */
-            test_attr_deprec(fcpl, my_fapl);                    /* Test deprecated API routines */
-            test_attr_many(new_format, fcpl, my_fapl);               /* Test storing lots of attributes */
-
-            /* New attribute API routine tests, on old-format storage */
-            test_attr_info_by_idx(new_format, fcpl, my_fapl);   /* Test querying attribute info by index */
-            test_attr_delete_by_idx(new_format, fcpl, my_fapl); /* Test deleting attribute by index */
-            test_attr_iterate2(new_format, fcpl, my_fapl);      /* Test iterating over attributes by index */
-            test_attr_open_by_idx(new_format, fcpl, my_fapl);   /* Test opening attributes by index */
-            test_attr_open_by_name(new_format, fcpl, my_fapl);  /* Test opening attributes by name */
-            test_attr_create_by_name(new_format, fcpl, my_fapl); /* Test creating attributes by name */
-
-            /* Tests that address specific bugs */
-            test_attr_bug1(fcpl, my_fapl);                      /* Test odd allocation operations */
-            test_attr_bug2(fcpl, my_fapl);                      /* Test many deleted attributes */
-            test_attr_bug3(fcpl, my_fapl);                      /* Test "self referential" attributes */
-            test_attr_bug4(fcpl, my_fapl);                      /* Test attributes on named datatypes */
-            test_attr_bug5(fcpl, my_fapl);                      /* Test opening/closing attributes through different file handles */
-            test_attr_bug6(fcpl, my_fapl);                      /* Test reading empty attribute */
-            /* Skip test_attr_bug7 because it is specific to the new object
-             * header format and in fact fails if used with the old format, due
-             * to the attributes being larger than 64K */
-            test_attr_bug8(fcpl, my_fapl);                      /* Test attribute expanding object header with undecoded messages */
-            test_attr_bug9(fcpl, my_fapl);                      /* Test large attributes converting to dense storage */
-        } /* end else */
-    } /* end for */
+
+                /* tests specific to the "new format" */
+                if (new_format == TRUE) {
+                    /* General attribute tests */
+                    test_attr_dense_create(my_fcpl, my_fapl);       /* Test dense attribute storage creation */
+                    test_attr_dense_open(my_fcpl, my_fapl);         /* Test opening attributes in dense storage */
+                    test_attr_dense_delete(my_fcpl, my_fapl);       /* Test deleting attributes in dense storage */
+                    test_attr_dense_rename(my_fcpl, my_fapl);       /* Test renaming attributes in dense storage */
+                    test_attr_dense_unlink(my_fcpl, my_fapl);       /* Test unlinking object with attributes in dense storage */
+                    test_attr_dense_limits(my_fcpl, my_fapl);       /* Test dense attribute storage limits */
+                    test_attr_dense_dup_ids(my_fcpl, my_fapl);      /* Test duplicated IDs for dense attribute storage */
+
+                    /* Attribute creation order tests */
+                    test_attr_corder_create_basic(my_fcpl, my_fapl);/* Test creating an object w/attribute creation order info */
+                    test_attr_corder_create_compact(my_fcpl, my_fapl);  /* Test compact attribute storage on an object w/attribute creation order info */
+                    test_attr_corder_create_dense(my_fcpl, my_fapl);/* Test dense attribute storage on an object w/attribute creation order info */
+                    test_attr_corder_create_reopen(my_fcpl, my_fapl);/* Test creating attributes w/reopening file from using new format to using old format */
+                    test_attr_corder_transition(my_fcpl, my_fapl);  /* Test attribute storage transitions on an object w/attribute creation order info */
+                    test_attr_corder_delete(my_fcpl, my_fapl);      /* Test deleting object using dense storage w/attribute creation order info */
+
+                    /* More complex tests with exclusively both "new format" and "shared" attributes */
+                    if(use_shared == TRUE) {
+                        test_attr_shared_write(my_fcpl, my_fapl);   /* Test writing to shared attributes in compact & dense storage */
+                        test_attr_shared_rename(my_fcpl, my_fapl);  /* Test renaming shared attributes in compact & dense storage */
+                        test_attr_shared_delete(my_fcpl, my_fapl);  /* Test deleting shared attributes in compact & dense storage */
+                        test_attr_shared_unlink(my_fcpl, my_fapl);  /* Test unlinking object with shared attributes in compact & dense storage */
+                    } /* if using shared attributes */
+
+                    test_attr_delete_last_dense(my_fcpl, my_fapl);
+
+                    /* test_attr_bug7 is specific to the "new" object header format,
+                     * and in fact fails if used with the old format due to the
+                     * attributes being larger than 64K */
+                    test_attr_bug7(my_fcpl, my_fapl);               /* Test creating and deleting large attributes in ohdr chunk 0 */
+
+                } /* if using "new format" */
+            } /* for unshared/shared attributes */
+        } /* for old/new format */
+
+        if (minimize_dset_oh != 0) {
+            ret = H5Pclose(dcpl);
+            CHECK(ret, FAIL, "H5Pclose");
+            dcpl_g = H5P_DEFAULT;
+        }
+
+    } /* for default/minimized dataset object headers */
 
     /* Close  FCPLs */
     ret = H5Pclose(fcpl);
diff --git a/test/tbogus.h5 b/test/tbogus.h5
index 91ab76f..efcbd79 100644
--- a/test/tbogus.h5
+++ b/test/tbogus.h5
diff --git a/test/test_filenotclosed.sh.in b/test/testabort_fail.sh.in
index 0b43c5b..925d8a4 100644
--- a/test/test_filenotclosed.sh.in
+++ b/test/testabort_fail.sh.in
@@ -13,6 +13,9 @@
 #
 # Test to verify that the assertion/abort failure is fixed when the application
 # does not close the file. (See HDFFV-10160)
+#
+# Test to verify that the infinite loop closing library/abort failure is fixed 
+# when the application creates and removes dense attributes (See HDFFV-10659)
 
 srcdir=@srcdir@
 
@@ -20,22 +23,44 @@ nerrors=0
 
 ##############################################################################
 ##############################################################################
-###			  T H E   T E S T                                              ###
+###			  T H E   T E S T S                                            ###
 ##############################################################################
 ##############################################################################
-
+#
+#
 echo "Testing file not closed assertion/abort failure"
 TEST_NAME=filenotclosed     # The test name
-TEST_BIN=`pwd`/$TEST_NAME 	# The path of the test binary
+TEST_BIN=`pwd`/$TEST_NAME   # The path of the test binary
 #
 # Run the test
-#$RUNSERIAL $TEST_BIN >/dev/null 2>&1 
-$RUNSERIAL $TEST_BIN 2>&1 
+$RUNSERIAL $TEST_BIN >/dev/null 2>&1 
 exitcode=$?
 if [ $exitcode -eq 0 ]; then
     echo "Test PASSED"
 else
+    echo "Test FAILED"
  	nerrors="`expr $nerrors + 1`"
-	echo "***Error encountered***"
 fi
-exit $nerrors
+#
+#
+echo "Testing infinite loop closing library/abort failure"
+TEST_NAME=del_many_dense_attrs  # The test name
+TEST_BIN=`pwd`/$TEST_NAME 	    # The path of the test binary
+# Run the test
+$RUNSERIAL $TEST_BIN >/dev/null 2>&1 
+exitcode=$?
+if [ $exitcode -eq 0 ]; then
+    echo "Test PASSED"
+else
+    echo "Test FAILED"
+ 	nerrors="`expr $nerrors + 1`"
+fi
+#
+#
+if test $nerrors -eq 0 ; then
+    echo "All tests for abort failure passed."
+    exit 0
+else
+    echo "Tests for abort failure failed with $nerrors errors."
+    exit 1
+fi
diff --git a/test/tfile.c b/test/tfile.c
index ad7f87f..2784204 100644
--- a/test/tfile.c
+++ b/test/tfile.c
@@ -4967,7 +4967,7 @@ test_libver_bounds_real(H5F_libver_t libver_create, unsigned oh_vers_create,
 #define VERBFNAME        "tverbounds_dspace.h5"
 #define VERBDSNAME       "dataset 1"
 #define SPACE1_DIM1     3
-static int
+static void
 test_libver_bounds_open(void)
 {
     hid_t file = -1;    /* File ID */
@@ -7051,6 +7051,132 @@ test_incr_filesize(void)
 
 /****************************************************************
 **
+**  test_min_dset_ohdr():
+**    Test API calls to toggle dataset object header minimization.
+**
+**  TODO (as separate function?):
+**    + setting persists between close and (re)open?
+**    + dataset header sizes created while changing value of toggle
+**
+****************************************************************/
+static void
+test_min_dset_ohdr(void)
+{
+    const char basename[]       = "min_dset_ohdr_testfile";
+    char filename[FILENAME_LEN] = "";
+    hid_t      file_id          = -1;
+    hid_t      file2_id         = -1;
+    hbool_t    minimize;
+    herr_t     ret;
+
+    MESSAGE(5, ("Testing dataset object header minimization\n"));
+
+    /*********/
+    /* SETUP */
+    /*********/
+
+    h5_fixname(basename, H5P_DEFAULT, filename, sizeof(filename));
+
+    file_id = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK_I(file_id, "H5Fcreate");
+
+    /*********/
+    /* TESTS */
+    /*********/
+
+    /*----------------------------------------
+     * TEST default value
+     */
+    ret = H5Fget_dset_no_attrs_hint(file_id, &minimize);
+    CHECK(ret, FAIL, "H5Fget_dset_no_attrs_hint");
+    VERIFY(minimize, FALSE, "minimize flag");
+
+    /*----------------------------------------
+     * TEST set to TRUE
+     */
+    ret = H5Fset_dset_no_attrs_hint(file_id, TRUE);
+    CHECK(ret, FAIL, "H5Fset_dset_no_attrs_hint");
+
+    ret = H5Fget_dset_no_attrs_hint(file_id, &minimize);
+    CHECK(ret, FAIL, "H5Fget_dset_no_attrs_hint");
+    VERIFY(minimize, TRUE, "minimize flag");
+
+    /*----------------------------------------
+     * TEST second file open on same filename
+     */
+    file2_id = H5Fopen(filename, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK_I(file2_id, "H5Fopen");
+
+    /* verify TRUE setting on second open
+     */
+    ret = H5Fget_dset_no_attrs_hint(file_id, &minimize);
+    CHECK(ret, FAIL, "H5Fget_dset_no_attrs_hint");
+    VERIFY(minimize, TRUE, "minimize flag");
+
+    /* re-set to FALSE on first open
+     */
+    ret = H5Fset_dset_no_attrs_hint(file_id, FALSE);
+    CHECK(ret, FAIL, "H5Fset_dset_no_attrs_hint");
+
+    /* verify FALSE set on both opens
+     */
+    ret = H5Fget_dset_no_attrs_hint(file_id, &minimize);
+    CHECK(ret, FAIL, "H5Fget_dset_no_attrs_hint");
+    VERIFY(minimize, FALSE, "minimize flag");
+
+    ret = H5Fget_dset_no_attrs_hint(file2_id, &minimize);
+    CHECK(ret, FAIL, "H5Fget_dset_no_attrs_hint");
+    VERIFY(minimize, FALSE, "minimize flag");
+
+    /* re-set to TRUE on second open
+     */
+    ret = H5Fset_dset_no_attrs_hint(file2_id, TRUE);
+    CHECK(ret, FAIL, "H5Fset_dset_no_attrs_hint");
+
+    /* verify TRUE set on both opens
+     */
+    ret = H5Fget_dset_no_attrs_hint(file_id, &minimize);
+    CHECK(ret, FAIL, "H5Fget_dset_no_attrs_hint");
+    VERIFY(minimize, TRUE, "minimize flag");
+
+    ret = H5Fget_dset_no_attrs_hint(file2_id, &minimize);
+    CHECK(ret, FAIL, "H5Fget_dset_no_attrs_hint");
+    VERIFY(minimize, TRUE, "minimize flag");
+
+    /*----------------------------------------
+     * TEST error cases
+     */
+
+    /* trying to set with invalid file ID */
+    H5E_BEGIN_TRY {
+        ret = H5Fset_dset_no_attrs_hint(-1, TRUE);
+    } H5E_END_TRY;
+    VERIFY(ret, FAIL, "H5Fset_dset_no_attrs_hint");
+
+    /* trying to get with invalid file ID */
+    H5E_BEGIN_TRY {
+        ret = H5Fget_dset_no_attrs_hint(-1, &minimize);
+    } H5E_END_TRY;
+    VERIFY(ret, FAIL, "H5Fget_dset_no_attrs_hint");
+
+    /* trying to get with invalid pointer */
+    H5E_BEGIN_TRY {
+        ret = H5Fget_dset_no_attrs_hint(file_id, NULL);
+    } H5E_END_TRY;
+    VERIFY(ret, FAIL, "H5Fget_dset_no_attrs_hint");
+
+    /************/
+    /* TEARDOWN */
+    /************/
+
+    ret = H5Fclose(file_id);
+    CHECK(ret, FAIL, "H5Fclose");
+    ret = H5Fclose(file2_id);
+    CHECK(ret, FAIL, "H5Fclose");
+} /* end test_min_dset_ohdr() */
+
+/****************************************************************
+**
 **  test_deprec():
 **    Test deprecated functionality.
 **
@@ -7336,6 +7462,7 @@ test_file(void)
     test_libver_macros();                       /* Test the macros for library version comparison */
     test_libver_macros2();                      /* Test the macros for library version comparison */
     test_incr_filesize();                       /* Test H5Fincrement_filesize() and H5Fget_eoa() */
+    test_min_dset_ohdr();                       /* Test datset object header minimization */
 #ifndef H5_NO_DEPRECATED_SYMBOLS
     test_deprec();                              /* Test deprecated routines */
 #endif /* H5_NO_DEPRECATED_SYMBOLS */
diff --git a/test/th5o.c b/test/th5o.c
index 63fee5f..2949c4e 100644
--- a/test/th5o.c
+++ b/test/th5o.c
@@ -13,7 +13,7 @@
 
 /***********************************************************
 *
-* Test program:	 th5o
+* Test program:     th5o
 *
 * Test public H5O functions for accessing
 *
@@ -30,7 +30,7 @@
 #define TEST6_DIM1 100
 #define TEST6_DIM2 100
 
-
+
 /****************************************************************
 **
 **  test_h5o_open(): Test H5Oopen function.
@@ -140,7 +140,7 @@ test_h5o_open(void)
 } /* test_h5o_open() */
 
 
-
+
 /****************************************************************
 **
 **  test_h5o_close(): Test H5Oclose function.
@@ -230,7 +230,7 @@ test_h5o_close(void)
     CHECK(ret, FAIL, "H5Fclose");
 }
 
-
+
 /****************************************************************
 **
 **  test_h5o_open_by_addr(): Test H5Oopen_by_addr function.
@@ -367,7 +367,7 @@ test_h5o_open_by_addr(void)
     VERIFY(dtype, FAIL, "H5Oopen_by_addr");
 } /* test_h5o_open_by_addr() */
 
-
+
 /****************************************************************
 **
 **  test_h5o_refcount(): Test H5O refcounting functions.
@@ -378,7 +378,7 @@ test_h5o_refcount(void)
 {
     hid_t       fid;                        /* HDF5 File ID      */
     hid_t       grp, dset, dtype, dspace;   /* Object identifiers */
-    H5O_info_t	oinfo;                      /* Object info struct */
+    H5O_info_t    oinfo;                      /* Object info struct */
     hsize_t     dims[RANK];
     herr_t      ret;                        /* Value returned from API calls */
 
@@ -562,7 +562,7 @@ test_h5o_refcount(void)
     CHECK(ret, FAIL, "H5Fclose");
 } /* test_h5o_refcount() */
 
-
+
 /****************************************************************
 **
 **  test_h5o_plist(): Test object creation properties
@@ -756,7 +756,7 @@ test_h5o_plist(void)
     CHECK(ret, FAIL, "H5Pclose");
 } /* test_h5o_plist() */
 
-
+
 /****************************************************************
 **
 **  test_h5o_link(): Test creating link to object
@@ -850,7 +850,7 @@ test_h5o_link(void)
             /* Verify the data */
             for(i = 0; i < (TEST6_DIM1 * TEST6_DIM2); i++)
                 VERIFY(wdata[i], rdata[i], "H5Dread");
-    
+
             /* Create a group with no name*/
             group_id = H5Gcreate_anon(file_id, H5P_DEFAULT, H5P_DEFAULT);
             CHECK(group_id, FAIL, "H5Gcreate_anon");
@@ -910,7 +910,7 @@ test_h5o_link(void)
     HDfree(rdata);
 } /* end test_h5o_link() */
 
-
+
 /****************************************************************
 **
 **  test_h5o_comment(): Test H5Oset(get)_comment functions.
@@ -1083,7 +1083,7 @@ test_h5o_comment(void)
 
 } /* test_h5o_comment() */
 
-
+
 /****************************************************************
 **
 **  test_h5o_comment_by_name(): Test H5Oset(get)_comment_by_name functions.
@@ -1242,7 +1242,7 @@ test_h5o_comment_by_name(void)
 
 } /* test_h5o_comment_by_name() */
 
-
+
 /****************************************************************
 **
 **  test_h5o_getinfo_same_file():  Test that querying the object info for
@@ -1254,7 +1254,7 @@ test_h5o_getinfo_same_file(void)
 {
     hid_t       fid1, fid2;             /* HDF5 File ID */
     hid_t       gid1, gid2;             /* Group IDs */
-    H5O_info_t	oinfo1, oinfo2;         /* Object info structs */
+    H5O_info_t    oinfo1, oinfo2;         /* Object info structs */
     herr_t      ret;                    /* Value returned from API calls */
 
     /* Create a new HDF5 file */
@@ -1353,7 +1353,7 @@ test_h5o_getinfo_same_file(void)
 /****************************************************************
 **
 **  visit_obj_cb():
-**      This is the callback function invoked by H5Ovisit1() in 
+**      This is the callback function invoked by H5Ovisit() in
 **      test_h5o_getinfo_visit():
 **      --Verify that the object info returned to the callback
 **        function is the same as H5Oget_info2().
@@ -1368,27 +1368,27 @@ visit_obj_cb(hid_t group_id, const char *name, const H5O_info_t *oinfo1,
     /* Verify the object info for "group1", "group2" and the root group */
     if(!(HDstrcmp(name, "group1"))) {
         H5Oget_info_by_name2(group_id, name, &oinfo2, H5O_INFO_NUM_ATTRS, H5P_DEFAULT);
-        VERIFY(oinfo1->num_attrs, oinfo2.num_attrs, "obj info from H5Ovisit1");
+        VERIFY(oinfo1->num_attrs, oinfo2.num_attrs, "obj info from H5Ovisit");
     } else if(!(HDstrcmp(name, "group2"))) {
         H5Oget_info_by_name2(group_id, name, &oinfo2, H5O_INFO_HDR, H5P_DEFAULT);
-        VERIFY(oinfo1->hdr.nmesgs, oinfo2.hdr.nmesgs, "obj info from H5Ovisit1/H5Oget_info2");
-        VERIFY(oinfo1->hdr.nchunks, oinfo2.hdr.nchunks, "obj info from H5Ovisit1/H5Oget_info2");
+        VERIFY(oinfo1->hdr.nmesgs, oinfo2.hdr.nmesgs, "obj info from H5Ovisit/H5Oget_info2");
+        VERIFY(oinfo1->hdr.nchunks, oinfo2.hdr.nchunks, "obj info from H5Ovisit/H5Oget_info2");
     } else if(!(HDstrcmp(name, "."))) {
         H5Oget_info_by_name2(group_id, name, &oinfo2, H5O_INFO_META_SIZE, H5P_DEFAULT);
-        VERIFY(oinfo1->meta_size.obj.index_size, oinfo2.meta_size.obj.index_size, "obj info from H5Ovisit1/H5Oget_info2");
-        VERIFY(oinfo1->meta_size.obj.heap_size, oinfo2.meta_size.obj.heap_size, "obj info from H5Ovisit1/H5Oget_info2");
+        VERIFY(oinfo1->meta_size.obj.index_size, oinfo2.meta_size.obj.index_size, "obj info from H5Ovisit/H5Oget_info2");
+        VERIFY(oinfo1->meta_size.obj.heap_size, oinfo2.meta_size.obj.heap_size, "obj info from H5Ovisit/H5Oget_info2");
     }
 
     return(H5_ITER_CONT);
 } /* end visit_obj_cb() */
 
-
+
 /****************************************************************
 **
-**  test_h5o_getinfo_visit():  
-**    Verify that the object info returned via H5Oget_info1()
+**  test_h5o_getinfo_visit():
+**    Verify that the object info returned via H5Oget_info()
 **    and H5Oget_info2() are the same.
-**    Verify that the object info retrieved via H5Ovisit1() is
+**    Verify that the object info retrieved via H5Ovisit() is
 **    the same as H5Oget_info2().
 **
 ****************************************************************/
@@ -1436,31 +1436,31 @@ test_h5o_getinfo_visit(void)
     HDmemset(&oinfo1, 0, sizeof(oinfo1));
     HDmemset(&oinfo2, 0, sizeof(oinfo2));
 
-    /* Query the object info for "group1" via H5Oget_info1 and H5Oget_info2 */
-    ret = H5Oget_info1(gid1, &oinfo1);
+    /* Query the object info for "group1" via H5Oget_info and H5Oget_info2 */
+    ret = H5Oget_info(gid1, &oinfo1);
     CHECK(ret, FAIL, "H5Oget_info");
     ret = H5Oget_info2(gid1, &oinfo2, H5O_INFO_BASIC|H5O_INFO_NUM_ATTRS);
     CHECK(ret, FAIL, "H5Oget_info");
 
     /* Verify the object info for "group1" is correct */
-    VERIFY(oinfo1.fileno, oinfo2.fileno, "obj info from H5Oget_info1/2");
-    VERIFY(oinfo1.num_attrs, oinfo2.num_attrs, "obj info from H5Oget_info1/2");
+    VERIFY(oinfo1.fileno, oinfo2.fileno, "obj info from H5Oget_info/2");
+    VERIFY(oinfo1.num_attrs, oinfo2.num_attrs, "obj info from H5Oget_info/2");
 
     /* Reset object info */
     HDmemset(&oinfo1, 0, sizeof(oinfo1));
     HDmemset(&oinfo2, 0, sizeof(oinfo2));
 
-    /* Query the object info for "group2" via H5Oget_info1 and H5Oget_info2 */
-    ret = H5Oget_info_by_name1(fid, "group2", &oinfo1, H5P_DEFAULT);
+    /* Query the object info for "group2" via H5Oget_info_by_name and H5Oget_info_by_name2 */
+    ret = H5Oget_info_by_name(fid, "group2", &oinfo1, H5P_DEFAULT);
     CHECK(ret, FAIL, "H5Oget_info_by_name");
     ret = H5Oget_info_by_name2(fid, "group2", &oinfo2, H5O_INFO_HDR|H5O_INFO_META_SIZE, H5P_DEFAULT);
     CHECK(ret, FAIL, "H5Oget_info_by_name");
 
     /* Verify the object info for "group2" is correct */
-    VERIFY(oinfo1.hdr.nmesgs, oinfo2.hdr.nmesgs, "obj info from H5Oget_info1/2");
-    VERIFY(oinfo1.hdr.nchunks, oinfo2.hdr.nchunks, "obj info from H5Oget_info1/2");
-    VERIFY(oinfo1.meta_size.obj.index_size, oinfo2.meta_size.obj.index_size, "obj info from H5Oget_info1/2");
-    VERIFY(oinfo1.meta_size.obj.heap_size, oinfo2.meta_size.obj.heap_size, "obj info from H5Oget_info1/2");
+    VERIFY(oinfo1.hdr.nmesgs, oinfo2.hdr.nmesgs, "obj info from H5Oget_info_by_name/2");
+    VERIFY(oinfo1.hdr.nchunks, oinfo2.hdr.nchunks, "obj info from H5Oget_info_by_name/2");
+    VERIFY(oinfo1.meta_size.obj.index_size, oinfo2.meta_size.obj.index_size, "obj info from H5Oget_info_by_name/2");
+    VERIFY(oinfo1.meta_size.obj.heap_size, oinfo2.meta_size.obj.heap_size, "obj info from H5Oget_info_by_name/2");
 
     /* Close everything */
     ret = H5Gclose(gid1);
@@ -1469,7 +1469,7 @@ test_h5o_getinfo_visit(void)
     CHECK(ret, FAIL, "H5Gclose");
 
     /* Verify the object info returned to the callback function is correct */
-    ret = H5Ovisit1(fid, H5_INDEX_NAME, H5_ITER_INC, visit_obj_cb, NULL);
+    ret = H5Ovisit(fid, H5_INDEX_NAME, H5_ITER_INC, visit_obj_cb, NULL);
 
     /* Close the file */
     ret = H5Fclose(fid);
@@ -1479,7 +1479,7 @@ test_h5o_getinfo_visit(void)
 
 #endif /* H5_NO_DEPRECATED_SYMBOLS */
 
-
+
 /****************************************************************
 **
 **  test_h5o(): Main H5O (generic object) testing routine.
@@ -1491,9 +1491,9 @@ test_h5o(void)
     /* Output message about test being performed */
     MESSAGE(5, ("Testing Objects\n"));
 
-    test_h5o_open();		/* Test generic open function */
-    test_h5o_open_by_addr();	/* Test opening objects by address */
-    test_h5o_close();		/* Test generic close function */
+    test_h5o_open();        /* Test generic open function */
+    test_h5o_open_by_addr();    /* Test opening objects by address */
+    test_h5o_close();        /* Test generic close function */
     test_h5o_refcount();        /* Test incrementing and decrementing reference count */
     test_h5o_plist();           /* Test object creation properties */
     test_h5o_link();            /* Test object link routine */
@@ -1501,19 +1501,19 @@ test_h5o(void)
     test_h5o_comment_by_name(); /* Test routines for comment by name */
     test_h5o_getinfo_same_file(); /* Test info for objects in the same file */
 #ifndef H5_NO_DEPRECATED_SYMBOLS
-    test_h5o_getinfo_visit();   /* Test object info for H5Oget_info1/2 and H5Ovisit1 */
+    test_h5o_getinfo_visit();   /* Test object info for H5Oget_info/2 and H5Ovisit */
 #endif
 } /* test_h5o() */
 
-
+
 /*-------------------------------------------------------------------------
- * Function:	cleanup_h5o
+ * Function:    cleanup_h5o
  *
- * Purpose:	Cleanup temporary test files
+ * Purpose:    Cleanup temporary test files
  *
- * Return:	none
+ * Return:    none
  *
- * Programmer:	James Laird
+ * Programmer:    James Laird
  *              June 3, 2006
  *
  *-------------------------------------------------------------------------
diff --git a/test/titerate.c b/test/titerate.c
index de652a7..093e8b5 100644
--- a/test/titerate.c
+++ b/test/titerate.c
@@ -20,6 +20,7 @@
 *************************************************************/
 
 #include "testhdf5.h"
+#include "H5srcdir.h"
 
 #define DATAFILE   "titerate.h5"
 
@@ -53,6 +54,17 @@ typedef struct {
     iter_enum command;      /* The type of return value */
 } iter_info;
 
+/* Definition for test_corrupted_attnamelen */
+#define CORRUPTED_ATNAMELEN_FILE   "corrupted_name_len.h5"
+#define DSET_NAME   "image"
+typedef struct searched_err_t {
+    char message[256];
+    bool found;
+} searched_err_t;
+
+/* Call back function for test_corrupted_attnamelen */
+static int find_err_msg_cb(unsigned n, const H5E_error2_t *err_desc, void *_client_data);
+
 /* Local functions */
 int iter_strcmp(const void *s1, const void *s2);
 int iter_strcmp2(const void *s1, const void *s2);
@@ -915,6 +927,92 @@ static void test_links(hid_t fapl)
     CHECK(ret, FAIL, "H5Fclose");
 } /* test_links() */
 
+/*-------------------------------------------------------------------------
+ * Function:    find_err_msg_cb
+ *
+ * Purpose:     Callback function to find the given error message.
+ *              Helper function for test_corrupted_attnamelen().
+ *
+ * Return:      H5_ITER_STOP when the message is found
+ *              H5_ITER_CONT, otherwise
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+find_err_msg_cb(unsigned n, const H5E_error2_t *err_desc, void *_client_data)
+{
+    int status = H5_ITER_CONT;
+    searched_err_t *searched_err = (searched_err_t *)_client_data;
+
+    if (searched_err == NULL)
+        return -1;
+
+    /* If the searched error message is found, stop the iteration */
+    if (err_desc->desc != NULL && strcmp(err_desc->desc, searched_err->message) == 0)
+    {
+        searched_err->found = true;
+        status = H5_ITER_STOP;
+    }
+    return status;
+} /* end find_err_msg_cb() */
+
+/**************************************************************************
+**
+**  test_corrupted_attnamelen(): Test the fix for the JIRA issue HDFFV-10588,
+**                      where corrupted attribute's name length can be
+**                      detected and invalid read can be avoided.
+**
+**************************************************************************/
+static void test_corrupted_attnamelen(void)
+{
+    hid_t          fid = -1;            /* File ID */
+    hid_t          did = -1;            /* Dataset ID */
+    searched_err_t err_caught;          /* Data to be passed to callback func */
+    int            err_status;          /* Status returned by H5Aiterate2 */
+    herr_t         ret;                 /* Return value */
+    const char *testfile = H5_get_srcdir_filename(CORRUPTED_ATNAMELEN_FILE); /* Corrected test file name */
+
+    const char *err_message = "attribute name has different length than stored length";
+                        /* the error message produced when the failure occurs */
+
+    /* Output message about test being performed */
+    MESSAGE(5, ("Testing the Handling of Corrupted Attribute's Name Length\n"));
+
+    fid = H5Fopen(testfile, H5F_ACC_RDONLY, H5P_DEFAULT);
+    CHECK(fid, FAIL, "H5Fopen");
+
+    /* Open the dataset */
+    did = H5Dopen2(fid, DSET_NAME, H5P_DEFAULT);
+    CHECK(did, FAIL, "H5Dopen2");
+
+    /* Call H5Aiterate2 to trigger the failure in HDFFV-10588.  Failure should
+       occur in the decoding stage, so some arguments are not needed. */
+    err_status = H5Aiterate2(did, H5_INDEX_NAME, H5_ITER_INC, NULL, NULL, NULL);
+
+    /* Make sure the intended error was caught */
+    if(err_status == -1)
+    {
+        /* Initialize client data */
+        HDstrcpy(err_caught.message, err_message);
+        err_caught.found = false;
+
+        /* Look for the correct error message */
+        ret = H5Ewalk2(H5E_DEFAULT, H5E_WALK_UPWARD, find_err_msg_cb, &err_caught);
+        CHECK(ret, FAIL, "H5Ewalk2");
+
+        /* Fail if the indicated message is not found */
+        CHECK(err_caught.found, false, "test_corrupted_attnamelen: Expected error not found");
+    }
+
+    /* Close the dataset and file */
+    ret = H5Dclose(did);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    ret = H5Fclose(fid);
+    CHECK(ret, FAIL, "H5Fclose");
+
+} /* test_corrupted_attnamelen() */
+
 /****************************************************************
 **
 **  test_iterate(): Main iteration testing routine.
@@ -951,6 +1049,9 @@ test_iterate(void)
         test_links(new_format ? fapl2 : fapl);              /* Test soft and hard link iteration */
     } /* end for */
 
+    /* Test the fix for issue HDFFV-10588 */
+    test_corrupted_attnamelen();
+
     /* Close FAPLs */
     ret = H5Pclose(fapl);
     CHECK(ret, FAIL, "H5Pclose");
diff --git a/test/tsohm.c b/test/tsohm.c
index d00a03a..93ba14f 100644
--- a/test/tsohm.c
+++ b/test/tsohm.c
@@ -178,40 +178,41 @@ static void test_sohm_extlink(void);
 
 /****************************************************************
 **
-**  check_fcpl_values(): Helper function for test_sohm_fcpl.
+**  verify_fcpl_values(): Helper function for test_sohm_fcpl.
 **         Verifies that the *_in and *_out parameters are equal.
 **
 ****************************************************************/
-static void check_fcpl_values(hid_t fcpl_id, const unsigned nindexes_in,
-                const unsigned *flags_in, const unsigned *minsizes_in,
+static void
+verify_fcpl_values(hid_t fcpl_id, const unsigned nindexes_expected,
+                const unsigned *flags_expected, const unsigned *minsizes_expected,
                 unsigned l2b, unsigned b2l)
 {
-    unsigned    num_indexes;
-    unsigned    index_flags, min_mesg_size;
-    unsigned    list_size, btree_size;
-    unsigned     x;
-    herr_t      ret;
-
-    /* Verify number of indexes is set to default */
-    ret = H5Pget_shared_mesg_nindexes(fcpl_id, &num_indexes);
+    unsigned  nindexes_actual;
+    unsigned  list_size;
+    unsigned  btree_size;
+    unsigned  x;
+    herr_t    ret;
+
+    /* Number of indexes */
+    ret = H5Pget_shared_mesg_nindexes(fcpl_id, &nindexes_actual);
     CHECK_I(ret, "H5Pget_shared_mesg_nindexes");
-    VERIFY(num_indexes, nindexes_in, "H5Pget_shared_mesg_nindexes");
-
-    /* Verify index flags and minsizes are set */
-    for(x=0; x<num_indexes; ++x)
-    {
-        ret = H5Pget_shared_mesg_index(fcpl_id, x, &index_flags, &min_mesg_size);
+    VERIFY(nindexes_actual, nindexes_expected, "H5Pget_shared_mesg_nindexes");
+    /* Index flags and minsizes */
+    for(x=0; x<nindexes_actual; ++x) {
+        unsigned flags_i;
+        unsigned min_mesg_size;
+        ret = H5Pget_shared_mesg_index(fcpl_id, x, &flags_i, &min_mesg_size);
         CHECK_I(ret, "H5Pget_shared_mesg_index");
-        VERIFY(index_flags, flags_in[x], "H5Pget_shared_mesg_index");
-        VERIFY(min_mesg_size, minsizes_in[x], "H5Pget_shared_mesg_index");
+        VERIFY(flags_i, flags_expected[x], "H5Pget_shared_mesg_index");
+        VERIFY(min_mesg_size, minsizes_expected[x], "H5Pget_shared_mesg_index");
     }
 
-    /* Check list-to-btree and btree-to-list values */
+    /* List-to-btree and btree-to-list values */
     ret = H5Pget_shared_mesg_phase_change(fcpl_id, &list_size, &btree_size);
     CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
     VERIFY(list_size, l2b, "H5Pset_shared_mesg_phase_change");
     VERIFY(btree_size, b2l, "H5Pset_shared_mesg_phase_change");
-}
+} /* verify_fcpl_values */
 
 
 /****************************************************************
@@ -219,7 +220,8 @@ static void check_fcpl_values(hid_t fcpl_id, const unsigned nindexes_in,
 **  test_sohm_fcpl(): Test File Creation Property Lists.
 **
 ****************************************************************/
-static void test_sohm_fcpl(void)
+static void
+test_sohm_fcpl(void)
 {
     hid_t       fid = -1;
     hid_t       fcpl_id = -1;
@@ -227,14 +229,12 @@ static void test_sohm_fcpl(void)
     unsigned    x;
     herr_t	ret;		/* Generic return value	*/
 
-    /* Output message about test being performed */
     MESSAGE(5, ("Testing File Creation Properties for Shared Messages\n"));
 
     fcpl_id = H5Pcreate(H5P_FILE_CREATE);
     CHECK_I(fcpl_id, "H5Pcreate");
 
-    /* Verify fcpl values */
-    check_fcpl_values(fcpl_id, DEF_NUM_INDEXES, def_type_flags, def_minsizes, DEF_L2B, DEF_B2L);
+    verify_fcpl_values(fcpl_id, DEF_NUM_INDEXES, def_type_flags, def_minsizes, DEF_L2B, DEF_B2L);
 
     /* Create a file with this fcpl and make sure that all the values can be
      * retrieved.
@@ -245,8 +245,7 @@ static void test_sohm_fcpl(void)
     fcpl2_id = H5Fget_create_plist(fid);
     CHECK_I(fcpl2_id, "H5Fcreate");
 
-    /* Verify fcpl values */
-    check_fcpl_values(fcpl2_id, DEF_NUM_INDEXES, def_type_flags, def_minsizes, DEF_L2B, DEF_B2L);
+    verify_fcpl_values(fcpl2_id, DEF_NUM_INDEXES, def_type_flags, def_minsizes, DEF_L2B, DEF_B2L);
 
     ret = H5Pclose(fcpl2_id);
     CHECK_I(ret, "H5Pclose");
@@ -262,8 +261,7 @@ static void test_sohm_fcpl(void)
     fcpl2_id = H5Fget_create_plist(fid);
     CHECK_I(ret, "H5Fcreate");
 
-    /* Verify fcpl values */
-    check_fcpl_values(fcpl2_id, DEF_NUM_INDEXES, def_type_flags, def_minsizes, DEF_L2B, DEF_B2L);
+    verify_fcpl_values(fcpl2_id, DEF_NUM_INDEXES, def_type_flags, def_minsizes, DEF_L2B, DEF_B2L);
 
     /* Clean up */
     ret = H5Pclose(fcpl2_id);
@@ -289,7 +287,7 @@ static void test_sohm_fcpl(void)
     ret = H5Pset_shared_mesg_phase_change(fcpl_id, TEST_L2B, TEST_B2L);
     CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
 
-    check_fcpl_values(fcpl_id, TEST_NUM_INDEXES, test_type_flags, test_minsizes, TEST_L2B, TEST_B2L);
+    verify_fcpl_values(fcpl_id, TEST_NUM_INDEXES, test_type_flags, test_minsizes, TEST_L2B, TEST_B2L);
 
     /* Use the fcpl to create a file and get it back again */
     fid = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, H5P_DEFAULT);
@@ -297,8 +295,7 @@ static void test_sohm_fcpl(void)
     fcpl2_id = H5Fget_create_plist(fid);
     CHECK_I(fcpl2_id, "H5Fcreate");
 
-    /* Verify fcpl values */
-    check_fcpl_values(fcpl2_id, TEST_NUM_INDEXES, test_type_flags, test_minsizes, TEST_L2B, TEST_B2L);
+    verify_fcpl_values(fcpl2_id, TEST_NUM_INDEXES, test_type_flags, test_minsizes, TEST_L2B, TEST_B2L);
 
     ret = H5Pclose(fcpl2_id);
     CHECK_I(ret, "H5Pclose");
@@ -314,8 +311,7 @@ static void test_sohm_fcpl(void)
     fcpl2_id = H5Fget_create_plist(fid);
     CHECK_I(ret, "H5Fcreate");
 
-    /* Verify fcpl values */
-    check_fcpl_values(fcpl2_id, TEST_NUM_INDEXES, test_type_flags, test_minsizes, TEST_L2B, TEST_B2L);
+    verify_fcpl_values(fcpl2_id, TEST_NUM_INDEXES, test_type_flags, test_minsizes, TEST_L2B, TEST_B2L);
 
     /* Clean up */
     ret = H5Pclose(fcpl2_id);
@@ -323,6 +319,72 @@ static void test_sohm_fcpl(void)
     ret = H5Fclose(fid);
     CHECK_I(ret, "H5Fclose");
 
+    /* Actually, the list max can be exactly 1 greater than the
+     * btree min, but no more.  Also, the errors above shouldn't
+     * have corrupted the fcpl, although we do need to reset the
+     * second index that we changed above.
+     */
+    ret = H5Pset_shared_mesg_index(fcpl_id, 1, test_type_flags[1], 15);
+    CHECK_I(ret, "H5Pset_shared_mesg_index");
+    ret = H5Pset_shared_mesg_phase_change(fcpl_id, 10, 11);
+    CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
+    fid = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, H5P_DEFAULT);
+    CHECK_I(fid, "H5Fcreate");
+    ret = H5Fclose(fid);
+    CHECK_I(ret, "H5Fclose");
+
+    /* Test edge cases; H5O_SHMESG_MAX_NINDEXES and H5O_SHMESG_MAX_LIST_SIZE should be
+     * valid values.  Also, creating a file with uninitialized indexes
+     * (indexes 3-5) should work.
+     */
+    ret = H5Pset_shared_mesg_nindexes(fcpl_id, H5O_SHMESG_MAX_NINDEXES);
+    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+    ret = H5Pset_shared_mesg_phase_change(fcpl_id, H5O_SHMESG_MAX_LIST_SIZE, H5O_SHMESG_MAX_LIST_SIZE);
+    CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
+    fid = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, H5P_DEFAULT);
+    CHECK_I(fid, "H5Fcreate");
+
+
+    /* Clean up */
+    ret = H5Pclose(fcpl_id);
+    CHECK_I(ret, "H5Pclose");
+    ret = H5Fclose(fid);
+    CHECK_I(ret, "H5Fclose");
+} /* test_sohm_fcpl */
+
+
+
+/****************************************************************
+**
+**  test_sohm_fcpl_errors(): Test bogus FCPL settings for SOHMs
+**
+****************************************************************/
+static void
+test_sohm_fcpl_errors(void)
+{
+    hid_t    fcpl_id = -1;
+    hid_t    fid     = -1;
+    unsigned x;
+    herr_t   ret;
+
+    MESSAGE(5, ("Testing bogus file creation properties for shared messages\n"));
+
+    fcpl_id = H5Pcreate(H5P_FILE_CREATE);
+    CHECK_I(fcpl_id, "H5Pcreate");
+
+    /* Set up index values */
+    ret = H5Pset_shared_mesg_nindexes(fcpl_id, TEST_NUM_INDEXES);
+    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+    for(x = 0; x < TEST_NUM_INDEXES; ++x) {
+        ret = H5Pset_shared_mesg_index(fcpl_id, x, test_type_flags[x], test_minsizes[x]);
+        CHECK_I(ret, "H5Pset_shared_mesg_index");
+    }
+
+    ret = H5Pset_shared_mesg_phase_change(fcpl_id, TEST_L2B, TEST_B2L);
+    CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
+
+    verify_fcpl_values(fcpl_id, TEST_NUM_INDEXES, test_type_flags, test_minsizes, TEST_L2B, TEST_B2L);
+
     /* Test giving bogus values to H5P* functions */
     H5E_BEGIN_TRY {
         /* Trying to create too many indexes should fail */
@@ -370,40 +432,7 @@ static void test_sohm_fcpl(void)
         ret = H5Pset_shared_mesg_phase_change(fcpl_id, H5O_SHMESG_MAX_LIST_SIZE, H5O_SHMESG_MAX_LIST_SIZE+1);
         VERIFY(ret, -1, "H5Pset_shared_mesg_phase_change");
     } H5E_END_TRY
-
-
-    /* Actually, the list max can be exactly 1 greater than the
-     * btree min, but no more.  Also, the errors above shouldn't
-     * have corrupted the fcpl, although we do need to reset the
-     * second index that we changed above.
-     */
-    ret = H5Pset_shared_mesg_index(fcpl_id, 1, test_type_flags[1], 15);
-    CHECK_I(ret, "H5Pset_shared_mesg_index");
-    ret = H5Pset_shared_mesg_phase_change(fcpl_id, 10, 11);
-    CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
-    fid = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, H5P_DEFAULT);
-    CHECK_I(fid, "H5Fcreate");
-    ret = H5Fclose(fid);
-    CHECK_I(ret, "H5Fclose");
-
-    /* Test edge cases; H5O_SHMESG_MAX_NINDEXES and H5O_SHMESG_MAX_LIST_SIZE should be
-     * valid values.  Also, creating a file with uninitialized indexes
-     * (indexes 3-5) should work.
-     */
-    ret = H5Pset_shared_mesg_nindexes(fcpl_id, H5O_SHMESG_MAX_NINDEXES);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-    ret = H5Pset_shared_mesg_phase_change(fcpl_id, H5O_SHMESG_MAX_LIST_SIZE, H5O_SHMESG_MAX_LIST_SIZE);
-    CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
-    fid = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, H5P_DEFAULT);
-    CHECK_I(fid, "H5Fcreate");
-
-
-    /* Clean up */
-    ret = H5Pclose(fcpl_id);
-    CHECK_I(ret, "H5Pclose");
-    ret = H5Fclose(fid);
-    CHECK_I(ret, "H5Fclose");
-}
+} /* test_sohm_fcpl_errors */
 
 
 /*-------------------------------------------------------------------------
@@ -455,7 +484,8 @@ error:
       H5Tclose(dtype1_id);
     } H5E_END_TRY
     return -1;
-}
+} /* make_dtype_1 */
+
 
 /*-------------------------------------------------------------------------
  * Function:    make_dtype_2
@@ -518,9 +548,9 @@ error:
       H5Tclose(int_id);
     } H5E_END_TRY
     return -1;
-}
-
+} /* make_dtype2 */
 
+
 /*-------------------------------------------------------------------------
  * Function:    close_reopen_file
  *
@@ -540,16 +570,16 @@ error:
 static hid_t
 close_reopen_file(hid_t file, const char* filename, hid_t fapl_id)
 {
-    hid_t fid;
-
-    if(H5Fclose(file) < 0) FAIL_STACK_ERROR
-    if((fid = H5Fopen(filename, H5F_ACC_RDWR, fapl_id)) < 0) FAIL_STACK_ERROR
-
-    return(fid);
+    if (H5Fclose(file) < 0)
+        FAIL_STACK_ERROR
+    file = H5Fopen(filename, H5F_ACC_RDWR, fapl_id);
+    if (file < 0)
+        FAIL_STACK_ERROR
+    return(file);
 
 error:
     return -1;
-}
+} /* close_reopen_file */
 
 
 /*-------------------------------------------------------------------------
@@ -557,7 +587,6 @@ error:
  *
  * Purpose:     Creates object headers that use a large datatype message.
  *
- *              Used in test_sohm_basic.  Should close the file ID passed in.
  *              Set test_file_closing to 1 to add file closing and reopening
  *              whenever possible (to test that SOHMs are written correctly
  *              on disk and not just in memory).
@@ -571,7 +600,7 @@ error:
  *-------------------------------------------------------------------------
  */
 static hid_t
-size1_helper(hid_t file, const char* filename, hid_t fapl_id, int test_file_closing)
+size1_helper(hid_t file, const char *filename, hid_t fapl_id, int test_file_closing)
 {
     dtype1_struct wdata;
     dtype1_struct rdata;
@@ -581,6 +610,32 @@ size1_helper(hid_t file, const char* filename, hid_t fapl_id, int test_file_clos
     hsize_t     dim1[1];
     int         x;
 
+/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ * Macro:      TSOHM_S1H_VERIFY_DATA
+ *
+ * Purpose:    Encapsulate a common pattern:
+ *             Reads the dataset and verifies that [a subset of] the data
+ *             are as expected.
+ *
+ * Programmer: Jacob Smith
+ *             2018 November 1
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ */
+#define TSOHM_S1H_VERIFY_DATA(dset_id, dtype_id) \
+{                                                \
+    HDmemset(&rdata, 0, sizeof(rdata));          \
+    if (0 > H5Dread((dset_id), (dtype_id), H5S_ALL, H5S_ALL, H5P_DEFAULT, &rdata)) { \
+        H5_FAILED(); AT();                       \
+        printf("Can't read data\n");             \
+        goto error;                              \
+    }                                            \
+    if ((rdata.i1 != wdata.i1) || (rdata.i2 != wdata.i2) || HDstrcmp(rdata.str, wdata.str)) { \
+        H5_FAILED(); AT();                       \
+        printf("incorrect read data\n");         \
+        goto error;                              \
+    }                                            \
+} /* TSOHM_S1H_VERIFY_DATA() definition */
+
     /* Closing and re-opening the file takes a long time on systems without
      * local disks.  Don't close and reopen if express testing is enabled.
      */
@@ -614,96 +669,55 @@ size1_helper(hid_t file, const char* filename, hid_t fapl_id, int test_file_clos
     /* Test writing and reading */
     if(H5Dwrite(dset_id, dtype1_id, H5S_ALL, H5S_ALL, H5P_DEFAULT, &wdata) < 0) FAIL_STACK_ERROR
 
-    if(H5Dread(dset_id, dtype1_id, H5S_ALL, H5S_ALL, H5P_DEFAULT, &rdata) < 0) FAIL_STACK_ERROR
-
-    if(rdata.i1 != wdata.i1 || rdata.i2 != wdata.i2 || HDstrcmp(rdata.str, wdata.str)) {
-        H5_FAILED(); AT();
-        printf("incorrect read data\n");
-        goto error;
-    } /* end if */
+    TSOHM_S1H_VERIFY_DATA(dset_id, dtype1_id)
     if(H5Dclose(dset_id) < 0) FAIL_STACK_ERROR
 
-    /* Close and re-open the file if requested*/
     if(test_file_closing)
         if((file = close_reopen_file(file, filename, fapl_id)) < 0) TEST_ERROR
 
-    /* Create more datasets with the same datatype */
-    if((dset_id = H5Dcreate2(file, DSETNAME[1], dtype1_id, space_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
-    if(H5Dclose(dset_id) < 0) FAIL_STACK_ERROR
+    /* Create 3 more datasets with the same datatype/dataspace */
+    for (x = 1; x < 4; x++) {
+        dset_id = H5Dcreate2(file, DSETNAME[x], dtype1_id, space_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+        if (0 > dset_id) FAIL_STACK_ERROR
+        if (x == 3)
+            if(H5Dwrite(dset_id, dtype1_id, H5S_ALL, H5S_ALL, H5P_DEFAULT, &wdata) < 0) TEST_ERROR
+        if (H5Dclose(dset_id) < 0) FAIL_STACK_ERROR
 
-    /* Close and re-open the file if requested*/
-    if(test_file_closing)
-        if((file = close_reopen_file(file, filename, fapl_id)) < 0) TEST_ERROR
-
-    if((dset_id = H5Dcreate2(file, DSETNAME[2], dtype1_id, space_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
-    if(H5Dclose(dset_id) < 0) TEST_ERROR
-
-    /* Close and re-open the file if requested*/
-    if(test_file_closing)
-        if((file = close_reopen_file(file, filename, fapl_id)) < 0) TEST_ERROR
-
-    if((dset_id = H5Dcreate2(file,DSETNAME[3],dtype1_id,space_id,H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
-
-    /* Write data to dataset 3 for later */
-    if(H5Dwrite(dset_id, dtype1_id, H5S_ALL, H5S_ALL, H5P_DEFAULT, &wdata) < 0) TEST_ERROR
+        if (test_file_closing)
+            if((file = close_reopen_file(file, filename, fapl_id)) < 0) TEST_ERROR
+    }
 
-    if(H5Dclose(dset_id) < 0) TEST_ERROR
     if(H5Tclose(dtype1_id) < 0) TEST_ERROR
 
-    /* Close and re-open the file if requested*/
-    if(test_file_closing)
-        if((file = close_reopen_file(file, filename, fapl_id)) < 0) TEST_ERROR
-
     /* Make sure the data has been written successfully */
-    if((dset_id = H5Dopen2(file, DSETNAME[0], H5P_DEFAULT)) < 0) TEST_ERROR
-    if((dtype1_id = H5Dget_type(dset_id)) < 0) TEST_ERROR
-
-    /* Read data back again */
-    HDmemset(&rdata, 0, sizeof(rdata));
-    if(H5Dread(dset_id, dtype1_id, H5S_ALL, H5S_ALL, H5P_DEFAULT, &rdata) < 0) {
-        H5_FAILED(); AT();
-        printf("Can't read data\n");
-        goto error;
-    } /* end if */
-
-    if(rdata.i1 != wdata.i1 || rdata.i2 != wdata.i2 || HDstrcmp(rdata.str, wdata.str)) {
-        H5_FAILED(); AT();
-        printf("incorrect read data\n");
-        goto error;
-    } /* end if */
+    dset_id = H5Dopen2(file, DSETNAME[0], H5P_DEFAULT);
+    if(dset_id < 0) TEST_ERROR
+    dtype1_id = H5Dget_type(dset_id);
+    if(dtype1_id < 0) TEST_ERROR
+    TSOHM_S1H_VERIFY_DATA(dset_id, dtype1_id)
 
     if(H5Dclose(dset_id) < 0) TEST_ERROR
 
-    /* Create several copies of the dataset (this increases the amount of space saved by sharing the datatype message) */
+    /* Create several copies of the dataset
+     * this increases the amount of space saved by sharing the datatype message
+     */
     for(x = 0; x < SOHM_HELPER_NUM_EX_DSETS; x++) {
         if((dset_id = H5Dcreate2(file, EXTRA_DSETNAME[x], dtype1_id, space_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
         if(H5Dclose(dset_id) < 0) TEST_ERROR
 
-        /* Close and re-open the file if requested*/
         if(test_file_closing)
             if((file = close_reopen_file(file, filename, fapl_id)) < 0) TEST_ERROR
-    } /* end for */
+    }
 
     if(H5Tclose(dtype1_id) < 0) TEST_ERROR
     if(H5Sclose(space_id) < 0) TEST_ERROR
 
     /* Ensure that we can still read data back from dataset 3 */
-    if((dset_id = H5Dopen2(file, DSETNAME[3], H5P_DEFAULT)) < 0) TEST_ERROR
-    if((dtype1_id = H5Dget_type(dset_id)) < 0) TEST_ERROR
-
-    /* Read data back again */
-    HDmemset(&rdata, 0, sizeof(rdata));
-    if(H5Dread(dset_id, dtype1_id, H5S_ALL, H5S_ALL, H5P_DEFAULT, &rdata) < 0) {
-        H5_FAILED(); AT();
-        printf("Can't read data\n");
-        goto error;
-    } /* end if */
-
-    if(rdata.i1 != wdata.i1 || rdata.i2 != wdata.i2 || HDstrcmp(rdata.str, wdata.str)) {
-        H5_FAILED(); AT();
-        printf("incorrect read data\n");
-        goto error;
-    } /* end if */
+    dset_id = H5Dopen2(file, DSETNAME[3], H5P_DEFAULT);
+    if(dset_id < 0) TEST_ERROR
+    dtype1_id = H5Dget_type(dset_id);
+    if(dtype1_id < 0) TEST_ERROR
+    TSOHM_S1H_VERIFY_DATA(dset_id, dtype1_id)
 
     if(H5Dclose(dset_id) < 0) TEST_ERROR
     if(H5Tclose(dtype1_id) < 0) TEST_ERROR
@@ -717,7 +731,42 @@ size1_helper(hid_t file, const char* filename, hid_t fapl_id, int test_file_clos
         H5Fclose(file);
     } H5E_END_TRY
     return -1;
-}
+#undef TSOHM_S1H_VERIFY_DATA /* macro is exclusive to this function */
+} /* size1_helper */
+
+
+/*----------------------------------------------------------------------------
+ * Function: getsize_testsize1
+ *
+ * Purpose: Creates a test file, populates it, and returns its file size.
+ *          Oject header information from the "first" dataset in the file
+ *          is stored in pointer `oinfo`.
+ *
+ * Programmer: Jacob Smith
+ *             2018 November 1
+ *----------------------------------------------------------------------------
+ */
+static h5_stat_size_t
+getsize_testsize1(const char *filename, hid_t fcpl_id, hid_t fapl_id, unsigned open_close, H5O_info_t *oinfo)
+{
+    hid_t file = -1;
+    herr_t ret;
+
+    file = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, fapl_id);
+    CHECK_I(file, "H5Fcreate");
+
+    file = size1_helper(file, FILENAME, fapl_id, open_close);
+    CHECK_I(file, "size1_helper");
+
+    ret = H5Oget_info_by_name2(file, DSETNAME[0], oinfo, H5O_INFO_HDR, H5P_DEFAULT);
+    CHECK_I(ret, "H5Oget_info_by_name");
+
+    ret = H5Fclose(file);
+    CHECK_I(ret, "H5Fclose");
+
+    return h5_get_file_size(FILENAME, fapl_id);
+} /* getsize_testsize1 */
+
 
 /*-------------------------------------------------------------------------
  * Function:    test_sohm_size1
@@ -727,17 +776,26 @@ size1_helper(hid_t file, const char* filename, hid_t fapl_id, int test_file_clos
  * Programmer:  James Laird
  *              Monday, April 10, 2006
  *
- * Modifications:
- *
  *-------------------------------------------------------------------------
  */
-static void test_sohm_size1(void)
+static void
+test_sohm_size1(void)
 {
     hid_t       file = -1;
     hid_t       fcpl_id = -1;
     hid_t       fapl_id = -1;
-    hsize_t     sohm_oh_size;
-    hsize_t     sohm_btree_oh_size;
+
+    unsigned       use_shared = 0;
+    unsigned       use_btree = 0;
+    unsigned       open_close = 0;
+    h5_stat_size_t file_sizes[9];
+    unsigned       size_index = 0;
+    hsize_t        oh_sizes[3];
+    unsigned       oh_size_index = 0;
+
+    hsize_t        norm_oh_size;
+    hsize_t        sohm_oh_size;
+    hsize_t        sohm_btree_oh_size;
     h5_stat_size_t norm_empty_filesize;
     h5_stat_size_t sohm_empty_filesize;
     h5_stat_size_t sohm_btree_empty_filesize;
@@ -747,6 +805,7 @@ static void test_sohm_size1(void)
     h5_stat_size_t norm_final_filesize2;
     h5_stat_size_t sohm_final_filesize2;
     h5_stat_size_t sohm_btree_final_filesize2;
+
     H5O_info_t  oinfo;
     unsigned    num_indexes = 1;
     unsigned    index_flags = H5O_SHMESG_DTYPE_FLAG;
@@ -757,7 +816,6 @@ static void test_sohm_size1(void)
 
     MESSAGE(5, ("Testing that shared datatypes save space\n"));
 
-
     /* Create a FAPL with "semi" close degree, to detect dangling IDs */
     fapl_id = H5Pcreate(H5P_FILE_ACCESS);
     CHECK_I(fapl_id, "H5Pcreate");
@@ -765,169 +823,97 @@ static void test_sohm_size1(void)
     ret = H5Pset_fclose_degree(fapl_id, H5F_CLOSE_SEMI);
     CHECK_I(ret, "H5Pset_fclose_degree");
 
-    /* Create a file with SOHMs disabled and get its size */
-    fcpl_id = H5Pcreate(H5P_FILE_CREATE);
-    CHECK_I(fcpl_id, "H5Pcreate");
-
-    ret = H5Pset_shared_mesg_nindexes(fcpl_id, 0);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-
-    file = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, fapl_id);
-    CHECK_I(file, "H5Fcreate");
-
-    ret = H5Fclose(file);
-    CHECK_I(ret, "H5Fclose");
-
-    /* Get the file size */
-    norm_empty_filesize = h5_get_file_size(FILENAME, fapl_id);
-
-    /* Add a bunch of large datatypes to the file */
-    file = H5Fopen(FILENAME, H5F_ACC_RDWR, fapl_id);
-    CHECK_I(file, "H5Fopen");
-    file = size1_helper(file, FILENAME, fapl_id, 0);
-    CHECK_I(file, "size1_helper");
-    ret = H5Fclose(file);
-    CHECK_I(ret, "H5Fclose");
-
-    /* Get the new file size */
-    norm_final_filesize = h5_get_file_size(FILENAME, fapl_id);
-
-    /* Use the same property list to create a new file. */
-    file = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, fapl_id);
-    CHECK_I(file, "H5Fcreate");
-
-    ret = H5Pclose(fcpl_id);
-    CHECK_I(ret, "H5Pclose");
-
-    /* Add the same large datatypes, but keep closing and re-opening the file */
-    file = size1_helper(file, FILENAME, fapl_id, 1);
-    CHECK_I(file, "size1_helper");
-    ret = H5Fclose(file);
-    CHECK_I(ret, "H5Fclose");
-
-    /* Get the file size */
-    norm_final_filesize2 = h5_get_file_size(FILENAME, fapl_id);
-
-
-
-    /* Now do the same thing for a file with SOHMs enabled */
-    /* Create FCPL with SOHMs enabled */
-    fcpl_id = H5Pcreate(H5P_FILE_CREATE);
-    CHECK_I(fcpl_id, "H5Pcreate");
-
-    /* Tests one index holding only datatype messages */
-    ret = H5Pset_shared_mesg_nindexes(fcpl_id, num_indexes);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-    ret = H5Pset_shared_mesg_index(fcpl_id, 0, index_flags, min_mesg_size);
-    CHECK_I(ret, "H5Pset_shared_mesg_index");
-    ret = H5Pset_shared_mesg_phase_change(fcpl_id, list_max, btree_min);
-    CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
-
-    /* Create a file */
-    file = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, fapl_id);
-    CHECK_I(file, "H5Fcreate");
-
-    ret = H5Fclose(file);
-    CHECK_I(ret, "H5Fclose");
-
-    sohm_empty_filesize = h5_get_file_size(FILENAME, fapl_id);
-
-    /* Add a bunch of datatypes to this file */
-    file = H5Fopen(FILENAME, H5F_ACC_RDWR, fapl_id);
-    CHECK_I(file, "H5Fopen");
-    file = size1_helper(file, FILENAME, fapl_id, 0);
-    CHECK_I(file, "size1_helper");
+    /* ----------------------------------------
+     * Run operations, accumulating file sizes to compare later.
+     */
+
+    for (use_shared = 0; use_shared < 2; use_shared++) {
+        for (use_btree = 0; use_btree < 2; use_btree++) {
+
+            /* cannot use btree indexing without shared messages; skip case */
+            if (use_btree && !use_shared)
+                continue;
+
+            fcpl_id = H5Pcreate(H5P_FILE_CREATE);
+            CHECK_I(fcpl_id, "H5Pcreate");
+
+            if (use_shared) {
+                /* Tests one index holding only datatype messages */
+                ret = H5Pset_shared_mesg_nindexes(fcpl_id, num_indexes);
+                CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+                ret = H5Pset_shared_mesg_index(fcpl_id, 0, index_flags, min_mesg_size);
+                CHECK_I(ret, "H5Pset_shared_mesg_index");
+
+                if (use_btree) {
+                    ret = H5Pset_shared_mesg_phase_change(fcpl_id, 0, 0);
+                } else {
+                    ret = H5Pset_shared_mesg_phase_change(fcpl_id, list_max, btree_min);
+                }
+                CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
+            } else {
+                ret = H5Pset_shared_mesg_nindexes(fcpl_id, 0);
+                CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+            }
+
+            file = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, fapl_id);
+            CHECK_I(file, "H5Fcreate");
+            ret = H5Fclose(file);
+            CHECK_I(ret, "H5Fclose");
 
-    /* Get the size of a dataset object header */
-    ret = H5Oget_info_by_name2(file, DSETNAME[0], &oinfo, H5O_INFO_HDR, H5P_DEFAULT);
-    CHECK_I(ret, "H5Oget_info_by_name");
-    ret = H5Fclose(file);
-    CHECK_I(ret, "H5Fclose");
-    sohm_oh_size = oinfo.hdr.space.total;
+            /* size of empty file */
+            file_sizes[size_index++] = h5_get_file_size(FILENAME, fapl_id);
 
-    /* Get the new file size */
-    sohm_final_filesize = h5_get_file_size(FILENAME, fapl_id);
+            /* size of populated file, with different populating behaviors */
+            for (open_close = 0; open_close < 2; open_close++)
+                file_sizes[size_index++] = getsize_testsize1(FILENAME, fcpl_id, fapl_id, open_close, &oinfo);
+            oh_sizes[oh_size_index++] = oinfo.hdr.space.total;
 
-    /* Use the same property list to create a new file. */
-    file = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, fapl_id);
-    CHECK_I(file, "H5Fcreate");
+            ret = H5Pclose(fcpl_id);
+            CHECK_I(ret, "H5Pclose");
+        } /* for btree/listed messages */
+    } /* for normal/shared messages */
 
-    ret = H5Pclose(fcpl_id);
+    ret = H5Pclose(fapl_id);
     CHECK_I(ret, "H5Pclose");
 
-    /* Add the same large datatypes, but keep closing and re-opening the file */
-    file = size1_helper(file, FILENAME, fapl_id, 1);
-    CHECK_I(file, "size1_helper");
-    ret = H5Fclose(file);
-    CHECK_I(ret, "H5Fclose");
-
-    /* Get the file size */
-    sohm_final_filesize2 = h5_get_file_size(FILENAME, fapl_id);
-
-
-
-    /* Create FCPL with SOHMs enabled that uses a B-tree index */
-    fcpl_id = H5Pcreate(H5P_FILE_CREATE);
-    CHECK_I(fcpl_id, "H5Pcreate");
-
-    /* Tests one index holding only datatype messages */
-    ret = H5Pset_shared_mesg_nindexes(fcpl_id, num_indexes);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-    ret = H5Pset_shared_mesg_index(fcpl_id, 0, index_flags, min_mesg_size);
-    CHECK_I(ret, "H5Pset_shared_mesg_index");
-    ret = H5Pset_shared_mesg_phase_change(fcpl_id, 0, 0);
-    CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
-
-    /* Create a file */
-    file = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, fapl_id);
-    CHECK_I(file, "H5Fcreate");
-
-    ret = H5Fclose(file);
-    CHECK_I(ret, "H5Fclose");
-
-    sohm_btree_empty_filesize = h5_get_file_size(FILENAME, fapl_id);
-
-    /* Add a bunch of datatypes to this file */
-    file = H5Fopen(FILENAME, H5F_ACC_RDWR, fapl_id);
-    CHECK_I(file, "H5Fopen");
-    file = size1_helper(file, FILENAME, fapl_id, 0);
-    CHECK_I(file, "size1_helper");
-
-    /* Get the size of a dataset object header */
-    ret = H5Oget_info_by_name2(file, DSETNAME[0], &oinfo, H5O_INFO_HDR, H5P_DEFAULT);
-    CHECK_I(ret, "H5Oget_info_by_name");
-    ret = H5Fclose(file);
-    CHECK_I(ret, "H5Fclose");
-    sohm_btree_oh_size = oinfo.hdr.space.total;
-
-    /* Get the new file size */
-    sohm_btree_final_filesize = h5_get_file_size(FILENAME, fapl_id);
-
-    /* Use the same property list to create a new file. */
-    file = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, fapl_id);
-    CHECK_I(file, "H5Fcreate");
+    /* sanity-check state of arrays */
+    VERIFY(9, size_index, "size_index");
+    VERIFY(3, oh_size_index, "oh_size_index");
 
-    ret = H5Pclose(fcpl_id);
-    CHECK_I(ret, "H5Pclose");
+    /* ----------------------------------------
+     * Check that all sizes make sense.
+     */
 
-    /* Add the same large datatypes, but keep closing and re-opening the file */
-    file = size1_helper(file, FILENAME, fapl_id, 1);
-    CHECK_I(file, "size1_helper");
-    ret = H5Fclose(file);
-    CHECK_I(ret, "H5Fclose");
+    /* Put result sizes into human-readable symbolic names.
+     * Order dependent on loop execution above.
+     */
+    norm_empty_filesize = file_sizes[0];
+    norm_final_filesize = file_sizes[1];
+    norm_final_filesize2 = file_sizes[2];
+    norm_oh_size = oh_sizes[0];
 
-    /* Get the file size */
-    sohm_btree_final_filesize2 = h5_get_file_size(FILENAME, fapl_id);
+    sohm_empty_filesize = file_sizes[3];
+    sohm_final_filesize = file_sizes[4];
+    sohm_final_filesize2 = file_sizes[5];
+    sohm_oh_size = oh_sizes[1];
 
+    sohm_btree_empty_filesize = file_sizes[6];
+    sohm_btree_final_filesize = file_sizes[7];
+    sohm_btree_final_filesize2 = file_sizes[8];
+    sohm_btree_oh_size = oh_sizes[2];
 
+    /* How the SOHM messages are stored shouldn't affect the
+     * size of the object header.
+     */
+    VERIFY(sohm_btree_oh_size, sohm_oh_size, "H5Oget_info_by_name");
 
-    /* Check that all sizes make sense */
+#if 0 /* TBD: lying comment or bug. See Jira HDFFV-10646 */
     /* Object headers in SOHM files should be smaller than normal object
-     * headers.  How the SOHM messages are stored shouldn't affect the
-     * size of the object header.
+     * headers.
      */
-    if(sohm_oh_size != sohm_btree_oh_size)
-        VERIFY(sohm_btree_oh_size, 1, "H5Oget_info_by_name");
+    if (sohm_oh_size >= norm_oh_size)
+        VERIFY(norm_oh_size, 1, "H5Oget_info_by_name");
+#endif /* Jira HDFFV-10646 */
 
     /* Both sohm files should be bigger than a normal file when empty.
      * It's hard to say whether a B-tree with no nodes allocated should be
@@ -950,15 +936,118 @@ static void test_sohm_size1(void)
     if(sohm_final_filesize > sohm_btree_final_filesize)
         VERIFY(sohm_final_filesize, 1, "h5_get_file_size");
 
-    /* This shouldn't change even if we open and close the file */
+    /* Comparative sizes shouldn't change even if we open and close the file */
+
     if(sohm_btree_final_filesize2 >= norm_final_filesize2)
         VERIFY(sohm_btree_final_filesize2, 1, "h5_get_file_size");
     if(sohm_final_filesize2 > sohm_btree_final_filesize2)
         VERIFY(sohm_final_filesize2, 1, "h5_get_file_size");
 
+} /* test_sohm_size1 */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    test_sohm_size_consistency_open_create
+ *
+ * Purpose:     Tests that header size is different depending on file open
+ *              procedure?
+ *              Uses "size1_helper" for file setup directed to a specific
+ *              file handle.
+ *
+ * Programmer:  Jacob Smith
+ *              2018 November 1
+ *
+ *-------------------------------------------------------------------------
+ */
+static void
+test_sohm_size_consistency_open_create(void)
+{
+    hid_t       file = -1;
+    hid_t       fcpl_id = -1;
+    hid_t       fapl_id = -1;
+    unsigned    use_btree;
+    hsize_t     oh_size_open;
+    hsize_t     oh_size_create;
+    H5O_info_t  oinfo;
+    unsigned    num_indexes = 1;
+    unsigned    index_flags = H5O_SHMESG_DTYPE_FLAG;
+    unsigned    min_mesg_size = 50;
+    unsigned    list_max = 11;
+    unsigned    btree_min = 10;
+    herr_t      ret;
+
+    MESSAGE(5, ("Testing that header size is consistent between H5Fopen and H5Fcreate\n"));
+
+    /* Create a FAPL with "semi" close degree, to detect dangling IDs */
+    fapl_id = H5Pcreate(H5P_FILE_ACCESS);
+    CHECK_I(fapl_id, "H5Pcreate");
+    ret = H5Pset_fclose_degree(fapl_id, H5F_CLOSE_SEMI);
+    CHECK_I(ret, "H5Pset_fclose_degree");
+
+    for (use_btree = 0; use_btree < 2; use_btree++) {
+        /* Create FCPL with SOHMs enabled
+         */
+        fcpl_id = H5Pcreate(H5P_FILE_CREATE);
+        CHECK_I(fcpl_id, "H5Pcreate");
+        ret = H5Pset_shared_mesg_nindexes(fcpl_id, num_indexes);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+        ret = H5Pset_shared_mesg_index(fcpl_id, 0, index_flags, min_mesg_size);
+        CHECK_I(ret, "H5Pset_shared_mesg_index");
+        if (use_btree) {
+            MESSAGE(5, ("----testing with btree index----\n"));
+            ret = H5Pset_shared_mesg_phase_change(fcpl_id, 0, 0);
+            CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
+        } else {
+            MESSAGE(5, ("----testing with normal index----\n"));
+            ret = H5Pset_shared_mesg_phase_change(fcpl_id, list_max, btree_min);
+            CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
+        }
+
+        /* Create empty file */
+        file = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, fapl_id);
+        CHECK_I(file, "H5Fcreate");
+        ret = H5Fclose(file);
+        CHECK_I(ret, "H5Fclose");
+
+        /* Test Open/Write
+         * Add messages to previously-created file */
+        file = H5Fopen(FILENAME, H5F_ACC_RDWR, fapl_id);
+        CHECK_I(file, "H5Fopen");
+        file = size1_helper(file, FILENAME, fapl_id, 0);
+        CHECK_I(file, "size1_helper");
+
+        /* Get the size of a dataset object header */
+	ret = H5Oget_info_by_name2(file, DSETNAME[0], &oinfo, H5O_INFO_HDR, H5P_DEFAULT);
+        CHECK_I(ret, "H5Oget_info_by_name");
+        oh_size_open = oinfo.hdr.space.total;
+
+        ret = H5Fclose(file);
+        CHECK_I(ret, "H5Fclose");
+
+        /* Test Create/Write
+         * Add messages to a newly-created file */
+        file = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, fapl_id);
+        CHECK_I(file, "H5Fcreate");
+        file = size1_helper(file, FILENAME, fapl_id, 0);
+        CHECK_I(file, "size1_helper");
+
+        /* Get the size of a dataset object header */
+        ret = H5Oget_info_by_name2(file, DSETNAME[0], &oinfo, H5O_INFO_HDR, H5P_DEFAULT);
+        CHECK_I(ret, "H5Oget_info_by_name");
+        oh_size_create = oinfo.hdr.space.total;
+
+        ret = H5Fclose(file);
+        CHECK_I(ret, "H5Fclose");
+
+        VERIFY(oh_size_create, oh_size_open, "H5Oget_info_by_name2");
+
+        ret = H5Pclose(fcpl_id);
+        CHECK_I(ret, "H5Pclose");
+    } /* for normal/btree indexing */
+
     ret = H5Pclose(fapl_id);
     CHECK_I(ret, "H5Pclose");
-}
+} /* test_sohm_size_consistency_open_create */
 
 
 /*-------------------------------------------------------------------------
@@ -966,149 +1055,110 @@ static void test_sohm_size1(void)
  *
  * Purpose:     Given an fcpl, tests creating attributes with and without
  *              committed datatypes.
+ *              Verify that an attribute can be written and read back.
+ *              Tests attribute on a Group.
+ *              Tests committed and non-committed datatypes.
+ *              Tests attribute access through `H5Aopen()`.
  *
  * Programmer:  James Laird
  *              Thursday, November 30, 2006
  *
  *-------------------------------------------------------------------------
  */
-static void sohm_attr_helper(hid_t fcpl_id)
+static void
+sohm_attr_helper(hid_t fcpl_id)
 {
     hid_t file_id;
-    hid_t type_id;
     hid_t space_id;
-    hid_t group_id;
-    hid_t attr_id, attr_id2;
     hsize_t dims = 2;
     int wdata[2] = {7, 42};
     int rdata[2];
     herr_t ret;
     size_t x;
+    unsigned op_index=0;
+#define TSOHM_SAH_OP_COUNT 3
+    const char *groupnames[TSOHM_SAH_OP_COUNT] = {
+        "group_for_nothing_special",
+        "group_for_commited_dtype",
+        "group_for_commited_dtype_and_other_ID_access",
+    };
 
-    /*----------------------------------------------------------------------------
-     *    Test attribute with transient datatype
-     */
-    /* Create a file using the fcpl */
     file_id = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, H5P_DEFAULT);
     CHECK_I(file_id, "H5Fcreate");
 
-    /* Create a normal datatype and dataset */
-    type_id = H5Tcopy(H5T_NATIVE_INT);
-    CHECK_I(type_id, "H5Tcopy");
     space_id = H5Screate_simple(1, &dims, &dims);
     CHECK_I(space_id, "H5Screate_simple");
 
-    /* Create and verify an attribute on a group */
-    group_id = H5Gcreate2(file_id, "group", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK_I(group_id, "H5Gcreate2");
-    attr_id = H5Acreate2(group_id, "attribute", type_id, space_id, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK_I(attr_id, "H5Acreate2");
-    ret = H5Awrite(attr_id, H5T_NATIVE_INT, wdata);
-    CHECK_I(ret, "H5Awrite");
-
-    /* Close the datatype and group */
-    ret = H5Tclose(type_id);
-    CHECK_I(ret, "H5Tclose");
-    ret = H5Gclose(group_id);
-    CHECK_I(ret, "H5Gclose");
-
-    /* Flush the file to force data to be written */
-    ret = H5Fflush(file_id, H5F_SCOPE_GLOBAL);
-    CHECK_I(ret, "H5Fflush");
-
-    /* Verify */
-    HDmemset(rdata, 0, sizeof(rdata));
-    ret = H5Aread(attr_id, H5T_NATIVE_INT, rdata);
-    CHECK_I(ret, "H5Aread");
-    for(x = 0; x < (size_t)dims; ++x)
-        VERIFY(rdata[x], wdata[x], "H5Aread");
-
-    /* Cleanup */
-    ret = H5Aclose(attr_id);
-    CHECK_I(ret, "H5Aclose");
-
-    /*----------------------------------------------------------------------------
-     *    Test attribute with committed datatype
+    /* loop:
+     * 0 - nothing special
+     * 1 - committed datatype
+     * 2 - committed datatype, read through second ID
      */
-    /* Repeat with a committed datatype */
-    type_id = H5Tcopy(H5T_NATIVE_INT);
-    CHECK_I(type_id, "H5Tcopy");
-    ret = H5Tcommit2(file_id, "datatype", type_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK_I(ret, "H5Tcommit2");
-
-    /* Create and verify an attribute */
-    group_id = H5Gcreate2(file_id, "another_group", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK_I(group_id, "H5Gcreate2");
-    attr_id = H5Acreate2(group_id, "attribute", type_id, space_id, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK_I(attr_id, "H5Acreate2");
-    ret = H5Awrite(attr_id, H5T_NATIVE_INT, wdata);
-    CHECK_I(ret, "H5Awrite");
-
-    /* Close the datatype and group */
-    ret = H5Tclose(type_id);
-    CHECK_I(ret, "H5Tclose");
-    ret = H5Gclose(group_id);
-    CHECK_I(ret, "H5Gclose");
-
-    /* Flush the file to force data to be written */
-    ret = H5Fflush(file_id, H5F_SCOPE_GLOBAL);
-    CHECK_I(ret, "H5Fflush");
+    for (op_index = 0; op_index < TSOHM_SAH_OP_COUNT; op_index++) {
+        hid_t type_id  = -1;
+        hid_t group_id = -1;
+        hid_t attr_id  = -1;
+        hid_t attr_id2 = -1;
+        hid_t attr_read_id;
 
-    /* Verify */
-    HDmemset(rdata, 0, sizeof(rdata));
-    ret = H5Aread(attr_id, H5T_NATIVE_INT, rdata);
-    CHECK_I(ret, "H5Aread");
-    for(x = 0; x < (size_t)dims; ++x)
-        VERIFY(rdata[x], wdata[x], "H5Aread");
+        /* create group in file with name unique to op_index */
+        group_id = H5Gcreate2(file_id, groupnames[op_index], H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+        CHECK_I(group_id, "H5Gcreate2");
 
-    /* Cleanup */
-    ret = H5Aclose(attr_id);
-    CHECK_I(ret, "H5Aclose");
+        type_id = H5Tcopy(H5T_NATIVE_INT);
+        CHECK_I(type_id, "H5Tcopy");
 
-    /*----------------------------------------------------------------------------
-     *    Test attribute operation with two ID handles
-     */
-    /* Create and verify an attribute */
-    group_id = H5Gcreate2(file_id, "yet_another_group", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK_I(group_id, "H5Gcreate2");
-
-    attr_id = H5Acreate2(group_id, "attribute", H5T_NATIVE_INT, space_id, H5P_DEFAULT, H5P_DEFAULT);
-    CHECK_I(attr_id, "H5Acreate2");
+        /* Commit the datatype for the latter iterations.
+         * Only do this ONCE.
+         */
+        if (op_index == 1) {
+            ret = H5Tcommit2(file_id, "datatype", type_id, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+            CHECK_I(ret, "H5Tcommit2");
+        }
 
-    /* Open the attribute to get another handle */
-    attr_id2 = H5Aopen(group_id, "attribute", H5P_DEFAULT);
-    CHECK_I(attr_id2, "H5Aopen");
+        attr_id = H5Acreate2(group_id, "attribute", type_id, space_id, H5P_DEFAULT, H5P_DEFAULT);
+        CHECK_I(attr_id, "H5Acreate2");
 
-    ret = H5Awrite(attr_id, H5T_NATIVE_INT, wdata);
-    CHECK_I(ret, "H5Awrite");
+        if (op_index == 2) {
+            /* Open the attribute to get another handle */
+            attr_id2 = H5Aopen(group_id, "attribute", H5P_DEFAULT);
+            CHECK_I(attr_id2, "H5Aopen");
+        }
 
-    /* Close the group */
-    ret = H5Gclose(group_id);
-    CHECK_I(ret, "H5Gclose");
+        ret = H5Awrite(attr_id, H5T_NATIVE_INT, wdata);
+        CHECK_I(ret, "H5Awrite");
 
-    /* Flush the file to force data to be written */
-    ret = H5Fflush(file_id, H5F_SCOPE_GLOBAL);
-    CHECK_I(ret, "H5Fflush");
+        ret = H5Gclose(group_id);
+        CHECK_I(ret, "H5Gclose");
+        ret = H5Tclose(type_id);
+        CHECK_I(ret, "H5Tclose")
 
-    /* Verify the data with another ID handle */
-    HDmemset(rdata, 0, sizeof(rdata));
-    ret = H5Aread(attr_id2, H5T_NATIVE_INT, rdata);
-    CHECK_I(ret, "H5Aread");
+        /* Flush the file to force data to be written */
+        ret = H5Fflush(file_id, H5F_SCOPE_GLOBAL);
+        CHECK_I(ret, "H5Fflush");
 
-    for(x = 0; x < (size_t)dims; ++x)
-        VERIFY(rdata[x], wdata[x], "H5Aread");
+        /* Verify */
+        attr_read_id = (op_index == 2) ? attr_id2 : attr_id;
+        HDmemset(rdata, 0, sizeof(rdata));
+        ret = H5Aread(attr_read_id, H5T_NATIVE_INT, rdata);
+        CHECK_I(ret, "H5Aread");
+        for(x = 0; x < (size_t)dims; ++x)
+            VERIFY(rdata[x], wdata[x], "H5Aread");
 
-    /* Cleanup */
-    ret = H5Aclose(attr_id);
-    CHECK_I(ret, "H5Aclose");
-    ret = H5Aclose(attr_id2);
-    CHECK_I(ret, "H5Aclose");
+        ret = H5Aclose(attr_id);
+        CHECK_I(ret, "H5Aclose");
+        if (attr_id2 > -1 ) {
+            ret = H5Aclose(attr_id2);
+            CHECK_I(ret, "H5Aclose");
+        }
+    } /* for each attribute operation */
 
     ret = H5Sclose(space_id);
     CHECK_I(ret, "H5Sclose");
     ret = H5Fclose(file_id);
     CHECK_I(ret, "H5Fclose");
-}
+#undef TSOHM_SAH_OP_COUNT
+} /* sohm_attr_helper */
 
 
 /*-------------------------------------------------------------------------
@@ -1125,101 +1175,160 @@ static void sohm_attr_helper(hid_t fcpl_id)
  *
  *-------------------------------------------------------------------------
  */
-static void test_sohm_attrs(void)
+static void
+test_sohm_attrs(void)
 {
     hid_t fcpl_id;
+    unsigned i = 0;
+#define TSOHM_TSA_NFLAGS_1 7
+    unsigned flags1[TSOHM_TSA_NFLAGS_1] = {
+        H5O_SHMESG_ATTR_FLAG,
+        H5O_SHMESG_SDSPACE_FLAG,
+        H5O_SHMESG_DTYPE_FLAG,
+        H5O_SHMESG_ATTR_FLAG | H5O_SHMESG_SDSPACE_FLAG,
+        H5O_SHMESG_SDSPACE_FLAG | H5O_SHMESG_DTYPE_FLAG,
+        H5O_SHMESG_ATTR_FLAG | H5O_SHMESG_DTYPE_FLAG,
+        H5O_SHMESG_ATTR_FLAG | H5O_SHMESG_SDSPACE_FLAG | H5O_SHMESG_DTYPE_FLAG,
+    };
+#define TSOHM_TSA_NFLAGS_2 6
+    unsigned flags2[TSOHM_TSA_NFLAGS_2][2] = {
+        {   H5O_SHMESG_ATTR_FLAG,
+            H5O_SHMESG_SDSPACE_FLAG | H5O_SHMESG_DTYPE_FLAG,
+        },
+        {   H5O_SHMESG_SDSPACE_FLAG,
+            H5O_SHMESG_ATTR_FLAG | H5O_SHMESG_DTYPE_FLAG,
+        },
+        {   H5O_SHMESG_DTYPE_FLAG,
+            H5O_SHMESG_ATTR_FLAG | H5O_SHMESG_SDSPACE_FLAG,
+        },
+        {   H5O_SHMESG_SDSPACE_FLAG | H5O_SHMESG_DTYPE_FLAG,
+            H5O_SHMESG_ATTR_FLAG,
+        },
+        {   H5O_SHMESG_ATTR_FLAG | H5O_SHMESG_DTYPE_FLAG,
+            H5O_SHMESG_SDSPACE_FLAG,
+        },
+        {   H5O_SHMESG_ATTR_FLAG | H5O_SHMESG_SDSPACE_FLAG,
+            H5O_SHMESG_DTYPE_FLAG,
+        },
+    };
+#define TSOHM_TSA_NFLAGS_3 5
+    unsigned flags3[TSOHM_TSA_NFLAGS_3][3] = {
+        {   H5O_SHMESG_ATTR_FLAG,
+            H5O_SHMESG_SDSPACE_FLAG,
+            H5O_SHMESG_DTYPE_FLAG,
+        },
+        {   H5O_SHMESG_DTYPE_FLAG,
+            H5O_SHMESG_ATTR_FLAG,
+            H5O_SHMESG_SDSPACE_FLAG,
+        },
+        {   H5O_SHMESG_SDSPACE_FLAG,
+            H5O_SHMESG_DTYPE_FLAG,
+            H5O_SHMESG_ATTR_FLAG,
+        },
+        {   0, /* first index does not hold a shared message type? */
+            H5O_SHMESG_SDSPACE_FLAG | H5O_SHMESG_DTYPE_FLAG,
+            H5O_SHMESG_ATTR_FLAG,
+        },
+        {   0, /* missing SDSPACE flag */
+            H5O_SHMESG_DTYPE_FLAG,
+            H5O_SHMESG_ATTR_FLAG,
+        },
+    };
     herr_t ret;
 
     MESSAGE(5, ("Testing that shared messages work with attributes\n"));
 
-    /* Create an fcpl with no shared messages */
+    /* No shared messages */
     fcpl_id = H5Pcreate(H5P_FILE_CREATE);
     CHECK_I(fcpl_id, "H5Pcreate");
     ret = H5Pset_shared_mesg_nindexes(fcpl_id, 0);
     CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
 
-    /* Make sure attributes can be read with these settings (they'd better!) */
-    sohm_attr_helper(fcpl_id);
-
-
-    /* Run tests with only one kind of message to be shared */
-    ret = H5Pset_shared_mesg_nindexes(fcpl_id, 1);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-    ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_ATTR_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-
-    /* Verify */
-    sohm_attr_helper(fcpl_id);
-
-    ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_SDSPACE_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-
-    sohm_attr_helper(fcpl_id);
-
-    ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_DTYPE_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-
-    sohm_attr_helper(fcpl_id);
-
-
-    /* Run with any two types shared */
-    ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_SDSPACE_FLAG | H5O_SHMESG_DTYPE_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-
-    sohm_attr_helper(fcpl_id);
-
-    ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_ATTR_FLAG | H5O_SHMESG_DTYPE_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-
-    sohm_attr_helper(fcpl_id);
-
-    ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_SDSPACE_FLAG | H5O_SHMESG_ATTR_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-
     sohm_attr_helper(fcpl_id);
 
+    ret = H5Pclose(fcpl_id);
+    CHECK_I(ret, "H5Pclose");
 
-    /* Run test with all three kinds of message shared */
-    ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_SDSPACE_FLAG | H5O_SHMESG_DTYPE_FLAG | H5O_SHMESG_ATTR_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+    /* One shared message index
+     */
+    for (i=0; i < TSOHM_TSA_NFLAGS_1; i++) {
+        fcpl_id = H5Pcreate(H5P_FILE_CREATE);
+        CHECK_I(fcpl_id, "H5Pcreate");
+        ret = H5Pset_shared_mesg_nindexes(fcpl_id, 1);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+        ret = H5Pset_shared_mesg_index(fcpl_id, 0, flags1[i], 2);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
 
-    sohm_attr_helper(fcpl_id);
+        sohm_attr_helper(fcpl_id);
 
+        ret = H5Pclose(fcpl_id);
+        CHECK_I(ret, "H5Pclose");
+    }
 
-    /* Try using two indexes */
-    ret = H5Pset_shared_mesg_nindexes(fcpl_id, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-    ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_ATTR_FLAG | H5O_SHMESG_DTYPE_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-    ret = H5Pset_shared_mesg_index(fcpl_id, 1, H5O_SHMESG_SDSPACE_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+    /* two shared message indices
+     */
+    for (i=0; i < TSOHM_TSA_NFLAGS_2; i++) {
+        fcpl_id = H5Pcreate(H5P_FILE_CREATE);
+        CHECK_I(fcpl_id, "H5Pcreate");
+        ret = H5Pset_shared_mesg_nindexes(fcpl_id, 2);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+        ret = H5Pset_shared_mesg_index(fcpl_id, 0, flags2[i][0], 2);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+        ret = H5Pset_shared_mesg_index(fcpl_id, 1, flags2[i][1], 2);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
 
-    sohm_attr_helper(fcpl_id);
+        sohm_attr_helper(fcpl_id);
 
-    ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_DTYPE_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+        ret = H5Pclose(fcpl_id);
+        CHECK_I(ret, "H5Pclose");
+    }
 
-    sohm_attr_helper(fcpl_id);
+    /* duplicate flags in separate indices causes problems
+     */
+    H5E_BEGIN_TRY {
+        fcpl_id = H5Pcreate(H5P_FILE_CREATE);
+        CHECK_I(fcpl_id, "H5Pcreate");
+        ret = H5Pset_shared_mesg_nindexes(fcpl_id, 2);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+        ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_ATTR_FLAG, 2);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+        ret = H5Pset_shared_mesg_index(fcpl_id, 1, H5O_SHMESG_ATTR_FLAG, 2);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+
+        ret = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, H5P_DEFAULT);
+        VERIFY(ret, -1, "H5Fcreate");
+
+        ret = H5Pclose(fcpl_id);
+        CHECK_I(ret, "H5Pclose");
+    } H5E_END_TRY;
 
-    ret = H5Pset_shared_mesg_index(fcpl_id, 1, H5O_SHMESG_ATTR_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+    /* three shared message indices
+     */
+    for (i=0; i < TSOHM_TSA_NFLAGS_3; i++) {
+        fcpl_id = H5Pcreate(H5P_FILE_CREATE);
+        CHECK_I(fcpl_id, "H5Pcreate");
+        ret = H5Pset_shared_mesg_nindexes(fcpl_id, 3);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+        ret = H5Pset_shared_mesg_index(fcpl_id, 0, flags3[i][0], 2);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+        ret = H5Pset_shared_mesg_index(fcpl_id, 1, flags3[i][1], 2);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+        ret = H5Pset_shared_mesg_index(fcpl_id, 2, flags3[i][2], 2);
+        CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
 
-    sohm_attr_helper(fcpl_id);
+        sohm_attr_helper(fcpl_id);
 
+        ret = H5Pclose(fcpl_id);
+        CHECK_I(ret, "H5Pclose");
+    }
 
-    /* One index for each kind of message */
-    ret = H5Pset_shared_mesg_nindexes(fcpl_id, 3);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-    ret = H5Pset_shared_mesg_index(fcpl_id, 2, H5O_SHMESG_SDSPACE_FLAG, 2);
-    CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
+#undef TSOHM_TSA_NFLAGS_1
+#undef TSOHM_TSA_NFLAGS_2
+#undef TSOHM_TSA_NFLAGS_3
 
-    sohm_attr_helper(fcpl_id);
+} /* test_sohm_attrs */
 
 
-    /* Close the FCPL */
-    ret = H5Pclose(fcpl_id);
-    CHECK_I(ret, "H5Pclose");
-}
 
 /*-------------------------------------------------------------------------
  * Function:    size2_verify_plist1
@@ -1233,7 +1342,8 @@ static void test_sohm_attrs(void)
  *
  *-------------------------------------------------------------------------
  */
-static void size2_verify_plist1(hid_t plist)
+static void
+size2_verify_plist1(hid_t plist)
 {
     size_t cd_nelmts;
     unsigned int cd_value;
@@ -1281,7 +1391,8 @@ static void size2_verify_plist1(hid_t plist)
 
     ret = H5Tclose(dtype1_id);
     CHECK_I(ret, "H5Tclose");
-}
+} /* size2_verify_plist1 */
+
 
 /*-------------------------------------------------------------------------
  * Function:    size2_verify_plist2
@@ -1295,7 +1406,8 @@ static void size2_verify_plist1(hid_t plist)
  *
  *-------------------------------------------------------------------------
  */
-static void size2_verify_plist2(hid_t plist)
+static void
+size2_verify_plist2(hid_t plist)
 {
     size_t cd_nelmts;
     unsigned int cd_value;
@@ -1352,7 +1464,7 @@ static void size2_verify_plist2(hid_t plist)
 
     ret = H5Tclose(dtype2_id);
     CHECK_I(ret, "H5Tclose");
-}
+} /* size2_verify_plist2 */
 
 #ifdef NOT_NOW
 
@@ -1382,7 +1494,7 @@ size2_dump_struct(const char *name, size2_helper_struct *sizes)
   printf("   interleaved: %llu \tdelta: %llu\n", (unsigned long long)sizes->interleaved, (unsigned long long)(sizes->interleaved - sizes->dsets2));
   printf("    attributes: %llu \tdelta: %llu\n", (unsigned long long)sizes->attrs1, (unsigned long long)(sizes->attrs1 - sizes->interleaved));
   printf("  attributes 2: %llu \tdelta: %llu\n", (unsigned long long)sizes->attrs2, (unsigned long long)(sizes->attrs2 - sizes->attrs1));
-}
+} /* size2_dump_struct */
 #endif /* NOT_NOW */
 
 
@@ -1573,15 +1685,14 @@ size2_helper(hid_t fcpl_id, int test_file_closing, size2_helper_struct *ret_size
     ret_sizes->dsets1 = h5_get_file_size(FILENAME, H5P_DEFAULT);
 
 
-    /* Now create a new group filled with datasets that use all different messages */
+    /* Create new group filled with datasets that use all different messages */
     file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
     CHECK_I(file_id, "H5Fopen");
     group_id = H5Gcreate2(file_id, "group", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
     CHECK_I(group_id, "H5Gcreate2");
 
     /* Create NUM_DATASETS datasets in the new group */
-    for(x=0; x<NUM_DATASETS; ++x)
-    {
+    for(x=0; x<NUM_DATASETS; ++x) {
         dset_id = H5Dcreate2(group_id, DSETNAME[x], dtype2_id, dspace2_id, H5P_DEFAULT, dcpl2_id, H5P_DEFAULT);
         CHECK_I(dset_id, "H5Dcreate2");
 
@@ -1604,7 +1715,7 @@ size2_helper(hid_t fcpl_id, int test_file_closing, size2_helper_struct *ret_size
             group_id = H5Gopen2(file_id, "group", H5P_DEFAULT);
             CHECK_I(group_id, "H5Gopen2");
         }
-    }
+    } /* for each dataset */
 
     /* Close file and get its size now */
     ret = H5Gclose(group_id);
@@ -1621,8 +1732,7 @@ size2_helper(hid_t fcpl_id, int test_file_closing, size2_helper_struct *ret_size
     CHECK_I(group_id, "H5Gcreate2");
 
     /* Create NUM_DATASETS datasets in the new group */
-    for(x=0; x<NUM_DATASETS; x+=2)
-    {
+    for(x=0; x<NUM_DATASETS; x+=2) {
         dset_id = H5Dcreate2(group_id, DSETNAME[x], dtype1_id, dspace1_id, H5P_DEFAULT, dcpl1_id, H5P_DEFAULT);
         CHECK_I(dset_id, "H5Dcreate2");
 
@@ -1658,7 +1768,7 @@ size2_helper(hid_t fcpl_id, int test_file_closing, size2_helper_struct *ret_size
             group_id = H5Gopen2(file_id, "interleaved group", H5P_DEFAULT);
             CHECK_I(group_id, "H5Gopen2");
         }
-    }
+    } /* for each even dataset */
 
     /* Close file and get its size now */
     ret = H5Gclose(group_id);
@@ -1700,7 +1810,7 @@ size2_helper(hid_t fcpl_id, int test_file_closing, size2_helper_struct *ret_size
             group_id = H5Gopen2(file_id, "group", H5P_DEFAULT);
             CHECK_I(group_id, "H5Gopen2");
         }
-    }
+    } /* for each attribute */
 
     /* Close file and get its size now */
     ret = H5Gclose(group_id);
@@ -1716,8 +1826,7 @@ size2_helper(hid_t fcpl_id, int test_file_closing, size2_helper_struct *ret_size
     group_id = H5Gopen2(file_id, "interleaved group", H5P_DEFAULT);
     CHECK_I(group_id, "H5Gopen2");
 
-    for(x=0; x<NUM_ATTRIBUTES; ++x)
-    {
+    for(x=0; x<NUM_ATTRIBUTES; ++x) {
         /* Create the same name and value for each attribute as before */
         attr_string1[0] = attr_name[0] = (char)((x / 10) + '0');
         attr_string1[1] = attr_name[1] = (char)((x % 10) + '0');
@@ -1740,7 +1849,8 @@ size2_helper(hid_t fcpl_id, int test_file_closing, size2_helper_struct *ret_size
             group_id = H5Gopen2(file_id, "interleaved group", H5P_DEFAULT);
             CHECK_I(group_id, "H5Gopen2");
         }
-    }
+    } /* for each attribute */
+
     /* Close file and get its size now */
     ret = H5Gclose(group_id);
     CHECK_I(ret, "H5Gclose");
@@ -1768,7 +1878,7 @@ size2_helper(hid_t fcpl_id, int test_file_closing, size2_helper_struct *ret_size
     CHECK_I(ret, "H5Pclose");
 
     return 0;
-}
+} /* size2_helper */
 
 
 /*-------------------------------------------------------------------------
@@ -1785,7 +1895,8 @@ size2_helper(hid_t fcpl_id, int test_file_closing, size2_helper_struct *ret_size
  *
  *-------------------------------------------------------------------------
  */
-static void size2_verify(void)
+static void
+size2_verify(void)
 {
     hid_t file_id = -1;
     hid_t dset_id=-1;
@@ -1957,7 +2068,7 @@ static void size2_verify(void)
         CHECK_I(attr1_id, "H5Aclose");
         ret = H5Aclose(attr2_id);
         CHECK_I(attr2_id, "H5Aclose");
-    }
+    } /* for each attribute */
 
     /* Close everything */
     ret = H5Tclose(attr_type_id);
@@ -1968,7 +2079,7 @@ static void size2_verify(void)
     CHECK_I(ret, "H5Gclose");
     ret = H5Fclose(file_id);
     CHECK_I(ret, "H5Fclose");
-}
+} /* size2_verify */
 
 
 /*-------------------------------------------------------------------------
@@ -1993,7 +2104,8 @@ static void size2_verify(void)
  *
  *-------------------------------------------------------------------------
  */
-static void test_sohm_size2(int close_reopen)
+static void
+test_sohm_size2(int close_reopen)
 {
     hid_t       fcpl_id = -1;
     /* Sizes for file with no shared messages at all */
@@ -2585,7 +2697,7 @@ static void test_sohm_size2(int close_reopen)
         VERIFY(0, 1, "h5_get_file_size");
     if((h5_stat_size_t)((float)share_tiny_index.attrs2 * OVERHEAD_ALLOWED) < type_space_index.attrs2)
         VERIFY(0, 1, "h5_get_file_size");
-} /* end test_sohm_size2() */
+} /* end test_sohm_size2() */ 
 
 
 /*-------------------------------------------------------------------------
@@ -2601,27 +2713,24 @@ static void test_sohm_size2(int close_reopen)
  *
  *-------------------------------------------------------------------------
  */
-static void delete_helper_write(hid_t file_id, hid_t *dspace_id, hid_t *dcpl_id, int x)
+static void
+delete_helper_write(hid_t file_id, hid_t *dspace_id, hid_t *dcpl_id, int x)
 {
     hid_t dset_id = -1;
     hid_t attr_id = -1;
     char wdata;
     herr_t ret;
 
-    /* Create dataset */
     dset_id = H5Dcreate2(file_id, DSETNAME[x], H5T_NATIVE_CHAR, dspace_id[x], H5P_DEFAULT, dcpl_id[x], H5P_DEFAULT);
     CHECK_I(dset_id, "H5Dcreate2");
 
-    /* Write data to dataset */
     wdata = (char)(x + 'a');
     ret = H5Dwrite(dset_id, H5T_NATIVE_CHAR, dspace_id[x], dspace_id[x], H5P_DEFAULT, &wdata);
     CHECK_I(ret, "H5Dwrite");
 
-    /* Create an attribute on the dataset. */
     attr_id = H5Acreate2(dset_id, "attr_name", H5T_NATIVE_CHAR, dspace_id[x], H5P_DEFAULT, H5P_DEFAULT);
     CHECK_I(attr_id, "H5Acreate2");
 
-    /* Write to attribute */
     ret = H5Awrite(attr_id, H5T_NATIVE_CHAR, &wdata);
     CHECK_I(ret, "H5Awrite");
 
@@ -2629,7 +2738,7 @@ static void delete_helper_write(hid_t file_id, hid_t *dspace_id, hid_t *dcpl_id,
     CHECK_I(ret, "H5Aclose");
     ret = H5Dclose(dset_id);
     CHECK_I(ret, "H5Dclose");
-}
+} /* delete_helper_write */
 
 
 /*-------------------------------------------------------------------------
@@ -2645,28 +2754,25 @@ static void delete_helper_write(hid_t file_id, hid_t *dspace_id, hid_t *dcpl_id,
  *
  *-------------------------------------------------------------------------
  */
-static void delete_helper_read(hid_t file_id, hid_t *dspace_id, int x)
+static void
+delete_helper_read(hid_t file_id, hid_t *dspace_id, int x)
 {
     hid_t dset_id = -1;
     hid_t attr_id = -1;
     char rdata;
     herr_t ret;
 
-    /* Open dataset */
     dset_id = H5Dopen2(file_id, DSETNAME[x], H5P_DEFAULT);
     CHECK_I(dset_id, "H5Dopen2");
 
-    /* Read */
     rdata = '\0';
     ret = H5Dread(dset_id, H5T_NATIVE_CHAR, dspace_id[x], dspace_id[x], H5P_DEFAULT, &rdata);
     CHECK_I(ret, "H5Dread");
     VERIFY(rdata, (x + 'a'), "H5Dread");
 
-    /* Open attribute */
     attr_id = H5Aopen(dset_id, "attr_name", H5P_DEFAULT);
     CHECK_I(attr_id, "H5Aopen");
 
-    /* Read */
     rdata = '\0';
     ret = H5Aread(attr_id, H5T_NATIVE_CHAR, &rdata);
     CHECK_I(ret, "H5Dread");
@@ -2677,7 +2783,7 @@ static void delete_helper_read(hid_t file_id, hid_t *dspace_id, int x)
     CHECK_I(ret, "H5Aclose");
     ret = H5Dclose(dset_id);
     CHECK_I(ret, "H5Dclose");
-}
+} /* delete_helper_read */
 
 
 /*-------------------------------------------------------------------------
@@ -2701,7 +2807,8 @@ static void delete_helper_read(hid_t file_id, hid_t *dspace_id, int x)
  *
  *-------------------------------------------------------------------------
  */
-static void delete_helper(hid_t fcpl_id, hid_t *dspace_id, hid_t *dcpl_id)
+static void
+delete_helper(hid_t fcpl_id, hid_t *dspace_id, hid_t *dcpl_id)
 {
     hid_t file_id=-1;
     int x;
@@ -2765,7 +2872,7 @@ static void delete_helper(hid_t fcpl_id, hid_t *dspace_id, hid_t *dcpl_id)
         VERIFY(norm_filesize, deleted_filesize, "h5_get_file_size");
     if(deleted_filesize > (h5_stat_size_t)((float)norm_filesize * OVERHEAD_ALLOWED))
         VERIFY(deleted_filesize, norm_filesize, "h5_get_file_size");
-}
+} /* delete_helper */
 
 
 /*-------------------------------------------------------------------------
@@ -2799,6 +2906,8 @@ test_sohm_delete(void)
     hsize_t dims[] = DELETE_DIMS;
     herr_t ret;
 
+    MESSAGE(5, ("Testing deletion of SOHMs\n"));
+
     /* Create a number of different dataspaces.
      * For simplicity, each dataspace has only one element.
      */
@@ -2914,13 +3023,14 @@ test_sohm_delete(void)
 
 
 /*-------------------------------------------------------------------------
- * Function:    test_sohm_delete_revert_helper
+ * Function:    verify_dset_create_and_delete_does_not_grow_file
  *
  * Purpose:     Tests that shared object header message deletion returns
  *              the file to its previous state using the supplied FCPL.
  *
- *              Creates shared messages and then deletes them.  Ensures
- *              that the file has not grown in size.
+ *              Creates a file according to the supplied FCPL,
+ *              then creates datasets and deletes them.
+ *              Done in two passes: once with one dataset, once with two.
  *
  * Programmer:  James Laird
  *              Wednesday, January 3, 2007
@@ -2930,7 +3040,7 @@ test_sohm_delete(void)
  *-------------------------------------------------------------------------
  */
 static int
-test_sohm_delete_revert_helper(hid_t fcpl_id)
+verify_dset_create_and_delete_does_not_grow_file(hid_t fcpl_id)
 {
     hid_t file_id;
     hid_t dspace_id;
@@ -3017,13 +3127,14 @@ test_sohm_delete_revert_helper(hid_t fcpl_id)
         return(0);
     else
         return(-1);
-} /* test_sohm_delete_revert_helper() */
+} /* verify_dset_create_and_delete_does_not_grow_file */
 
 
 /*-------------------------------------------------------------------------
  * Function:    test_sohm_delete_revert
  *
- * Purpose:     Calls test_sohm_delete_revert_helper with different FCPLs.
+ * Purpose:     Verifies that creation and deletion of datasets with shared
+ *              message headers will not increase file size.
  *
  * Programmer:  James Laird
  *              Wednesday, January 3, 2007
@@ -3038,6 +3149,8 @@ test_sohm_delete_revert(void)
     hid_t fcpl_id;
     herr_t ret;
 
+    MESSAGE(5, ("Testing that file reverts to original size on SOHM deletion\n"));
+
     /* Create an fcpl with messages in two indexes */
     fcpl_id = H5Pcreate(H5P_FILE_CREATE);
     CHECK_I(fcpl_id, "H5Pcreate");
@@ -3049,14 +3162,14 @@ test_sohm_delete_revert(void)
     CHECK_I(ret, "H5Pset_shared_mesg_index");
 
     /* Call the helper function to test this FCPL. */
-    ret = test_sohm_delete_revert_helper(fcpl_id);
-    CHECK_I(ret, "test_sohm_delete_revert_helper");
+    ret = verify_dset_create_and_delete_does_not_grow_file(fcpl_id);
+    CHECK_I(ret, "verify_dset_create_and_delete_does_not_grow_file");
 
     /* Try using B-trees */
     ret = H5Pset_shared_mesg_phase_change(fcpl_id, 0, 0);
     CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
-    ret = test_sohm_delete_revert_helper(fcpl_id);
-    CHECK_I(ret, "test_sohm_delete_revert_helper");
+    ret = verify_dset_create_and_delete_does_not_grow_file(fcpl_id);
+    CHECK_I(ret, "verify_dset_create_and_delete_does_not_grow_file");
 
 
     /* Try sharing all messages */
@@ -3067,14 +3180,14 @@ test_sohm_delete_revert(void)
     ret = H5Pset_shared_mesg_phase_change(fcpl_id, 10, 5);
     CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
 
-    ret = test_sohm_delete_revert_helper(fcpl_id);
-    CHECK_I(ret, "test_sohm_delete_revert_helper");
+    ret = verify_dset_create_and_delete_does_not_grow_file(fcpl_id);
+    CHECK_I(ret, "verify_dset_create_and_delete_does_not_grow_file");
 
     /* Try using B-trees */
     ret = H5Pset_shared_mesg_phase_change(fcpl_id, 0, 0);
     CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
-    ret = test_sohm_delete_revert_helper(fcpl_id);
-    CHECK_I(ret, "test_sohm_delete_revert_helper");
+    ret = verify_dset_create_and_delete_does_not_grow_file(fcpl_id);
+    CHECK_I(ret, "verify_dset_create_and_delete_does_not_grow_file");
 
     /* There should be at least two messages in the test (datatype and
      * dataspace).  Use an index that will transition from a list to
@@ -3082,8 +3195,8 @@ test_sohm_delete_revert(void)
      */
     ret = H5Pset_shared_mesg_phase_change(fcpl_id, 1, 2);
     CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
-    ret = test_sohm_delete_revert_helper(fcpl_id);
-    CHECK_I(ret, "test_sohm_delete_revert_helper");
+    ret = verify_dset_create_and_delete_does_not_grow_file(fcpl_id);
+    CHECK_I(ret, "verify_dset_create_and_delete_does_not_grow_file");
 
 
     /* Try with shared messages enabled, but when messages are too big
@@ -3091,16 +3204,16 @@ test_sohm_delete_revert(void)
      */
     ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_ALL_FLAG, 35);
     CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
-    ret = test_sohm_delete_revert_helper(fcpl_id);
-    CHECK_I(ret, "test_sohm_delete_revert_helper");
+    ret = verify_dset_create_and_delete_does_not_grow_file(fcpl_id);
+    CHECK_I(ret, "verify_dset_create_and_delete_does_not_grow_file");
 
     ret = H5Pclose(fcpl_id);
     CHECK_I(ret, "H5Pclose");
-}
+} /* test_sohm_delete_revert */
 
 
 /*-------------------------------------------------------------------------
- * Function:    test_sohm_extlink_helper
+ * Function:    verify_dset_create_and_open_through_extlink_with_sohm
  *
  * Purpose:     Tests that a dataset created through an external link can
  *              be opened (that shared messages were created or not and
@@ -3113,7 +3226,8 @@ test_sohm_delete_revert(void)
  *
  *-------------------------------------------------------------------------
  */
-static void test_sohm_extlink_helper(hid_t src_fcpl_id, hid_t dst_fcpl_id)
+static void
+verify_dset_create_and_open_through_extlink_with_sohm(hid_t src_fcpl_id, hid_t dst_fcpl_id)
 {
     hid_t src_file_id = -1;
     hid_t dst_file_id = -1;
@@ -3164,7 +3278,7 @@ static void test_sohm_extlink_helper(hid_t src_fcpl_id, hid_t dst_fcpl_id)
     CHECK_I(ret, "H5Dclose");
     ret = H5Fclose(dst_file_id);
     CHECK_I(ret, "H5Fclose");
-}
+} /* verify_dset_create_and_open_through_extlink_with_sohm */
 
 
 /*-------------------------------------------------------------------------
@@ -3186,7 +3300,8 @@ test_sohm_extlink(void)
     hid_t fcpl_id = -1;
     herr_t ret;
 
-    /* Create fcpl */
+    MESSAGE(5, ("Testing SOHM creation through external links\n"));
+
     fcpl_id = H5Pcreate(H5P_FILE_CREATE);
     CHECK_I(fcpl_id, "H5Pcreate");
     ret = H5Pset_shared_mesg_nindexes(fcpl_id, 1);
@@ -3194,20 +3309,17 @@ test_sohm_extlink(void)
     ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_ALL_FLAG, 16);
     CHECK_I(ret, "H5Pset_shared_mesg_index");
 
-    /* Test using external links when the source or destination file uses
-     * shared messages
-     */
-    test_sohm_extlink_helper(fcpl_id, H5P_DEFAULT);
-    test_sohm_extlink_helper(H5P_DEFAULT, fcpl_id);
-    test_sohm_extlink_helper(fcpl_id, fcpl_id);
+    verify_dset_create_and_open_through_extlink_with_sohm(fcpl_id, H5P_DEFAULT);
+    verify_dset_create_and_open_through_extlink_with_sohm(H5P_DEFAULT, fcpl_id);
+    verify_dset_create_and_open_through_extlink_with_sohm(fcpl_id, fcpl_id);
 
     ret = H5Pclose(fcpl_id);
     CHECK_I(ret, "H5Pclose");
-}
+} /* test_sohm_extlink */
 
 
 /*-------------------------------------------------------------------------
- * Function:    test_sohm_extend_dset_helper
+ * Function:    verify_dataset_extension
  *
  * Purpose:     Tests extending a dataset's dataspace when sharing is
  *              enabled.
@@ -3223,7 +3335,7 @@ test_sohm_extlink(void)
  *-------------------------------------------------------------------------
  */
 static int
-test_sohm_extend_dset_helper(hid_t fcpl_id, hbool_t close_reopen)
+verify_dataset_extension(hid_t fcpl_id, hbool_t close_reopen)
 {
     hid_t file_id = -1;
     hid_t orig_space_id = -1;
@@ -3239,10 +3351,95 @@ test_sohm_extend_dset_helper(hid_t fcpl_id, hbool_t close_reopen)
     int old_nerrs;              /* Number of errors when entering this routine */
     herr_t ret;
 
-    /* Retrieve the current # of reported errors */
+    hsize_t *space_dims[3];
+
+/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ * Macro:      TSOHM_VDE_VERIFY_SPACES
+ *
+ * Purpose:    Encapsulate a common pattern
+ *             Open, read-verify, and close the dataspaces for datasets 1-3
+ *
+ * Programmer: Jacob Smith
+ *             2018 November 5
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ */
+#define TSOHM_VDE_VERIFY_SPACES(dims)                                     \
+{                                                                         \
+    /* Open dataspaces                                                    \
+     */                                                                   \
+    space1_id = H5Dget_space(dset1_id);                                   \
+    CHECK_I(space1_id, "H5Dget_space");                                   \
+    space2_id = H5Dget_space(dset2_id);                                   \
+    CHECK_I(space2_id, "H5Dget_space");                                   \
+    space3_id = H5Dget_space(dset3_id);                                   \
+    CHECK_I(space3_id, "H5Dget_space");                                   \
+    /* Verify dataspaces                                                  \
+     */                                                                   \
+    ret = H5Sget_simple_extent_dims(space1_id, out_dims, out_maxdims);    \
+    CHECK_I(ret, "H5Sget_simple_extent_dims");                            \
+    for(x=0; x<EXTEND_NDIMS; ++x) {                                       \
+        VERIFY(out_dims[x], (dims)[0][x], "H5Sget_simple_extent_dims");   \
+        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims"); \
+    }                                                                     \
+    ret = H5Sget_simple_extent_dims(space2_id, out_dims, out_maxdims);    \
+    CHECK_I(ret, "H5Sget_simple_extent_dims");                            \
+    for(x=0; x<EXTEND_NDIMS; ++x) {                                       \
+        VERIFY(out_dims[x], (dims)[1][x], "H5Sget_simple_extent_dims");   \
+        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims"); \
+    }                                                                     \
+    ret = H5Sget_simple_extent_dims(space3_id, out_dims, out_maxdims);    \
+    CHECK_I(ret, "H5Sget_simple_extent_dims");                            \
+    for(x=0; x<EXTEND_NDIMS; ++x) {                                       \
+        VERIFY(out_dims[x], (dims)[2][x], "H5Sget_simple_extent_dims");   \
+        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims"); \
+    }                                                                     \
+    /* Close dataspaces                                                   \
+     */                                                                   \
+    CHECK_I(H5Sclose(space1_id), "H5Sclose");                             \
+    CHECK_I(H5Sclose(space2_id), "H5Sclose");                             \
+    CHECK_I(H5Sclose(space3_id), "H5Sclose");                             \
+} /* define TSOHM_VDE_VERIFY_SPACES */
+
+/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ * Macro:      TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS()
+ *
+ * Purpose:    Encapsulate a common pattern
+ *             Wrapper to close and reopen file and datasets:
+ *                + "dataset" (dset_id)
+ *                + if n > 1 then include "dataset2" (dset_id2)
+ *                + if n > 2 then include "dataset3" (dset_id3)
+ *                + file (file_id)
+ *
+ * Programmer: Jacob Smith
+ *             2018 November 5
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ */
+#define TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(n)               \
+{                                                              \
+    CHECK_I(H5Dclose(dset1_id), "H5Dclose");                   \
+    if ((n) > 1)                                               \
+        CHECK_I(H5Dclose(dset2_id), "H5Dclose");               \
+    if ((n) > 2)                                               \
+        CHECK_I(H5Dclose(dset3_id), "H5Dclose");               \
+    CHECK_I(H5Fclose(file_id), "H5Fclose");                    \
+                                                               \
+    file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);    \
+    CHECK_I(file_id, "H5Fopen");                               \
+    dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);      \
+    CHECK_I(dset1_id, "H5Dopen2");                             \
+    if ((n) > 1) {                                             \
+        dset2_id = H5Dopen2(file_id, "dataset2", H5P_DEFAULT); \
+        CHECK_I(dset2_id, "H5Dopen2");                         \
+    }                                                          \
+    if ((n) > 2) {                                             \
+        dset3_id = H5Dopen2(file_id, "dataset3", H5P_DEFAULT); \
+        CHECK_I(dset3_id, "H5Dopen2");                         \
+    }                                                          \
+} /* define TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS */
+
+    /* Remember the current # of reported errors */
     old_nerrs = GetTestNumErrs();
 
-    /* Create file */
     file_id = H5Fcreate(FILENAME, H5F_ACC_TRUNC, fcpl_id, H5P_DEFAULT);
     CHECK_I(file_id, "H5Fcreate");
 
@@ -3258,250 +3455,52 @@ test_sohm_extend_dset_helper(hid_t fcpl_id, hbool_t close_reopen)
     dset1_id = H5Dcreate2(file_id, "dataset", H5T_NATIVE_LONG, orig_space_id, H5P_DEFAULT, dcpl_id, H5P_DEFAULT);
     CHECK_I(dset1_id, "H5Dcreate2");
 
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
-
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-    }
+    if(close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(1);
 
     /* Create another dataset starting with the same dataspace */
     dset2_id = H5Dcreate2(file_id, "dataset2", H5T_NATIVE_LONG, orig_space_id, H5P_DEFAULT, dcpl_id, H5P_DEFAULT);
     CHECK_I(dset2_id, "H5Dcreate2");
 
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset2_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
-
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-        dset2_id = H5Dopen2(file_id, "dataset2", H5P_DEFAULT);
-        CHECK_I(dset2_id, "H5Dopen2");
-    }
+    if(close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(2);
 
     /* Create a third dataset with the same dataspace */
     dset3_id = H5Dcreate2(file_id, "dataset3", H5T_NATIVE_LONG, orig_space_id, H5P_DEFAULT, dcpl_id, H5P_DEFAULT);
     CHECK_I(dset3_id, "H5Dcreate2");
 
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset2_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset3_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
-
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-        dset2_id = H5Dopen2(file_id, "dataset2", H5P_DEFAULT);
-        CHECK_I(dset2_id, "H5Dopen2");
-        dset3_id = H5Dopen2(file_id, "dataset3", H5P_DEFAULT);
-        CHECK_I(dset3_id, "H5Dopen2");
-    }
+    if(close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(3);
 
     /* Extend the first dataset */
     ret = H5Dset_extent(dset1_id, dims2);
     CHECK_I(ret, "H5Dset_extent");
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset2_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset3_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
-
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-        dset2_id = H5Dopen2(file_id, "dataset2", H5P_DEFAULT);
-        CHECK_I(dset2_id, "H5Dopen2");
-        dset3_id = H5Dopen2(file_id, "dataset3", H5P_DEFAULT);
-        CHECK_I(dset3_id, "H5Dopen2");
-    }
-
-    /* Get the dataspaces from the datasets */
-    space1_id = H5Dget_space(dset1_id);
-    CHECK_I(space1_id, "H5Dget_space");
-    space2_id = H5Dget_space(dset2_id);
-    CHECK_I(space2_id, "H5Dget_space");
-    space3_id = H5Dget_space(dset3_id);
-    CHECK_I(space3_id, "H5Dget_space");
-
-    /* Verify the dataspaces */
-    ret = H5Sget_simple_extent_dims(space1_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims2[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
-
-    ret = H5Sget_simple_extent_dims(space2_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims1[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
-
-    ret = H5Sget_simple_extent_dims(space3_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims1[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
+    if(close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(3);
 
-    /* Close all three dataspaces */
-    ret = H5Sclose(space1_id);
-    CHECK_I(ret, "H5Sclose");
-    ret = H5Sclose(space2_id);
-    CHECK_I(ret, "H5Sclose");
-    ret = H5Sclose(space3_id);
-    CHECK_I(ret, "H5Sclose");
+    space_dims[0] = dims2;
+    space_dims[1] = dims1;
+    space_dims[2] = dims1;
+    TSOHM_VDE_VERIFY_SPACES(space_dims);
 
     /* Extend the second dataset */
     ret = H5Dset_extent(dset2_id, dims2);
     CHECK_I(ret, "H5Dset_extent");
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset2_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset3_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
-
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-        dset2_id = H5Dopen2(file_id, "dataset2", H5P_DEFAULT);
-        CHECK_I(dset2_id, "H5Dopen2");
-        dset3_id = H5Dopen2(file_id, "dataset3", H5P_DEFAULT);
-        CHECK_I(dset3_id, "H5Dopen2");
-    }
+    if(close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(3);
 
-    /* Get the dataspaces from the datasets */
-    space1_id = H5Dget_space(dset1_id);
-    CHECK_I(space1_id, "H5Dget_space");
-    space2_id = H5Dget_space(dset2_id);
-    CHECK_I(space2_id, "H5Dget_space");
-    space3_id = H5Dget_space(dset3_id);
-    CHECK_I(space3_id, "H5Dget_space");
-
-    /* Verify the dataspaces */
-    ret = H5Sget_simple_extent_dims(space1_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims2[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
-
-    ret = H5Sget_simple_extent_dims(space2_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims2[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
-
-    ret = H5Sget_simple_extent_dims(space3_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims1[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
-
-    /* Close all three dataspaces */
-    ret = H5Sclose(space1_id);
-    CHECK_I(ret, "H5Sclose");
-    ret = H5Sclose(space2_id);
-    CHECK_I(ret, "H5Sclose");
-    ret = H5Sclose(space3_id);
-    CHECK_I(ret, "H5Sclose");
+    space_dims[1] = dims2;
+    TSOHM_VDE_VERIFY_SPACES(space_dims);
 
     /* Extend the third dataset */
     ret = H5Dset_extent(dset3_id, dims2);
     CHECK_I(ret, "H5Dset_extent");
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset2_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset3_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
 
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-        dset2_id = H5Dopen2(file_id, "dataset2", H5P_DEFAULT);
-        CHECK_I(dset2_id, "H5Dopen2");
-        dset3_id = H5Dopen2(file_id, "dataset3", H5P_DEFAULT);
-        CHECK_I(dset3_id, "H5Dopen2");
-    }
-
-    /* Get the dataspaces from the datasets */
-    space1_id = H5Dget_space(dset1_id);
-    CHECK_I(space1_id, "H5Dget_space");
-    space2_id = H5Dget_space(dset2_id);
-    CHECK_I(space2_id, "H5Dget_space");
-    space3_id = H5Dget_space(dset3_id);
-    CHECK_I(space3_id, "H5Dget_space");
-
-    /* Verify the dataspaces */
-    ret = H5Sget_simple_extent_dims(space1_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims2[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
+    if(close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(3);
 
-    ret = H5Sget_simple_extent_dims(space2_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims2[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
-
-    ret = H5Sget_simple_extent_dims(space3_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims2[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
-
-    /* Close all three dataspaces */
-    ret = H5Sclose(space1_id);
-    CHECK_I(ret, "H5Sclose");
-    ret = H5Sclose(space2_id);
-    CHECK_I(ret, "H5Sclose");
-    ret = H5Sclose(space3_id);
-    CHECK_I(ret, "H5Sclose");
+    space_dims[2] = dims2;
+    TSOHM_VDE_VERIFY_SPACES(space_dims);
 
     /* Close the datasets and file */
     ret = H5Dclose(dset1_id);
@@ -3523,164 +3522,44 @@ test_sohm_extend_dset_helper(hid_t fcpl_id, hbool_t close_reopen)
     CHECK_I(file_id, "H5Fcreate");
     dset1_id = H5Dcreate2(file_id, "dataset", H5T_NATIVE_LONG, orig_space_id, H5P_DEFAULT, dcpl_id, H5P_DEFAULT);
     CHECK_I(dset1_id, "H5Dcreate2");
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
-
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-    }
+    if (close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(1);
 
     /* Extend the first dataset */
     ret = H5Dset_extent(dset1_id, dims2);
     CHECK_I(ret, "H5Dset_extent");
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
-
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-    }
+    if (close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(1);
 
     /* Create the second dataset.  Its dataspace will be unshared and then
      * become shared when extended.
      */
     dset2_id = H5Dcreate2(file_id, "dataset2", H5T_NATIVE_LONG, orig_space_id, H5P_DEFAULT, dcpl_id, H5P_DEFAULT);
     CHECK_I(dset2_id, "H5Dcreate2");
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset2_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
-
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-        dset2_id = H5Dopen2(file_id, "dataset2", H5P_DEFAULT);
-        CHECK_I(dset2_id, "H5Dopen2");
-    }
+    if (close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(2);
 
     /* Extend the second dataset */
     ret = H5Dset_extent(dset2_id, dims2);
     CHECK_I(ret, "H5Dset_extent");
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset2_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
-
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-        dset2_id = H5Dopen2(file_id, "dataset2", H5P_DEFAULT);
-        CHECK_I(dset2_id, "H5Dopen2");
-    }
+    if (close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(2);
 
     /* Create the third dataset.  Its dataspace will be unshared and then
      * become shared when extended.
      */
     dset3_id = H5Dcreate2(file_id, "dataset3", H5T_NATIVE_LONG, orig_space_id, H5P_DEFAULT, dcpl_id, H5P_DEFAULT);
     CHECK_I(dset3_id, "H5Dcreate2");
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset2_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset3_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
-
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-        dset2_id = H5Dopen2(file_id, "dataset2", H5P_DEFAULT);
-        CHECK_I(dset2_id, "H5Dopen2");
-        dset3_id = H5Dopen2(file_id, "dataset3", H5P_DEFAULT);
-        CHECK_I(dset3_id, "H5Dopen2");
-    }
+    if (close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(3);
 
     /* Extend the third dataset */
     ret = H5Dset_extent(dset3_id, dims2);
     CHECK_I(ret, "H5Dset_extent");
-    if(close_reopen) {
-        /* If requested, close all open IDs and reopen them */
-        ret = H5Dclose(dset1_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset2_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Dclose(dset3_id);
-        CHECK_I(ret, "H5Dclose");
-        ret = H5Fclose(file_id);
-        CHECK_I(ret, "H5Fclose");
-
-        file_id = H5Fopen(FILENAME, H5F_ACC_RDWR, H5P_DEFAULT);
-        CHECK_I(file_id, "H5Fopen");
-        dset1_id = H5Dopen2(file_id, "dataset", H5P_DEFAULT);
-        CHECK_I(dset1_id, "H5Dopen2");
-        dset2_id = H5Dopen2(file_id, "dataset2", H5P_DEFAULT);
-        CHECK_I(dset2_id, "H5Dopen2");
-        dset3_id = H5Dopen2(file_id, "dataset3", H5P_DEFAULT);
-        CHECK_I(dset3_id, "H5Dopen2");
-    }
-
-    /* Get the dataspaces from the datasets */
-    space1_id = H5Dget_space(dset1_id);
-    CHECK_I(space1_id, "H5Dget_space");
-    space2_id = H5Dget_space(dset2_id);
-    CHECK_I(space2_id, "H5Dget_space");
-    space3_id = H5Dget_space(dset3_id);
-    CHECK_I(space3_id, "H5Dget_space");
-
-    /* Verify the dataspaces */
-    ret = H5Sget_simple_extent_dims(space1_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims2[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
-
-    ret = H5Sget_simple_extent_dims(space2_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims2[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
-
-    ret = H5Sget_simple_extent_dims(space3_id, out_dims, out_maxdims);
-    CHECK_I(ret, "H5Sget_simple_extent_dims");
-    for(x=0; x<EXTEND_NDIMS; ++x) {
-        VERIFY(out_dims[x], dims2[x], "H5Sget_simple_extent_dims");
-        VERIFY(out_maxdims[x], max_dims[x], "H5Sget_simple_extent_dims");
-    }
+    if (close_reopen)
+        TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS(3);
 
-    /* Close all three dataspaces */
-    ret = H5Sclose(space1_id);
-    CHECK_I(ret, "H5Sclose");
-    ret = H5Sclose(space2_id);
-    CHECK_I(ret, "H5Sclose");
-    ret = H5Sclose(space3_id);
-    CHECK_I(ret, "H5Sclose");
+    TSOHM_VDE_VERIFY_SPACES(space_dims);
 
     /* Close the datasets and file */
     ret = H5Dclose(dset1_id);
@@ -3698,12 +3577,15 @@ test_sohm_extend_dset_helper(hid_t fcpl_id, hbool_t close_reopen)
     ret = H5Pclose(dcpl_id);
     CHECK_I(ret, "H5Pclose");
 
-    /* Retrieve current # of errors */
+    /* Complaini if this test generated errors */
     if(old_nerrs == GetTestNumErrs())
         return(0);
     else
         return(-1);
-} /* end test_sohm_extend_dset_helper() */
+/* macros are exclusive to this function */
+#undef TSOHM_VDE_CLOSE_REOPEN_FILE_AND_DSETS
+#undef TSOHM_VDE_VERIFY_SPACES
+} /* verify_dataset_extension */
 
 
 /*-------------------------------------------------------------------------
@@ -3726,7 +3608,8 @@ test_sohm_extend_dset(void)
     hid_t fcpl_id = -1;
     herr_t ret;
 
-    /* Create fcpl */
+    MESSAGE(5, ("Testing extending shared dataspaces\n"));
+
     fcpl_id = H5Pcreate(H5P_FILE_CREATE);
     CHECK_I(fcpl_id, "H5Pcreate");
 
@@ -3735,20 +3618,20 @@ test_sohm_extend_dset(void)
     CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
 
     /* No shared messages */
-    ret = test_sohm_extend_dset_helper(fcpl_id, FALSE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
-    ret = test_sohm_extend_dset_helper(fcpl_id, TRUE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
+    ret = verify_dataset_extension(fcpl_id, FALSE);
+    CHECK_I(ret, "verify_dataset_extension");
+    ret = verify_dataset_extension(fcpl_id, TRUE);
+    CHECK_I(ret, "verify_dataset_extension");
 
 
     /* Only dataspaces */
     ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_SDSPACE_FLAG, 16);
     CHECK_I(ret, "H5Pset_shared_mesg_index");
 
-    ret = test_sohm_extend_dset_helper(fcpl_id, FALSE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
-    ret = test_sohm_extend_dset_helper(fcpl_id, TRUE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
+    ret = verify_dataset_extension(fcpl_id, FALSE);
+    CHECK_I(ret, "verify_dataset_extension");
+    ret = verify_dataset_extension(fcpl_id, TRUE);
+    CHECK_I(ret, "verify_dataset_extension");
 
     /* All messages */
     ret = H5Pset_shared_mesg_nindexes(fcpl_id, 1);
@@ -3756,44 +3639,44 @@ test_sohm_extend_dset(void)
     ret = H5Pset_shared_mesg_index(fcpl_id, 0, H5O_SHMESG_ALL_FLAG, 16);
     CHECK_I(ret, "H5Pset_shared_mesg_index");
 
-    ret = test_sohm_extend_dset_helper(fcpl_id, FALSE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
-    ret = test_sohm_extend_dset_helper(fcpl_id, TRUE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
+    ret = verify_dataset_extension(fcpl_id, FALSE);
+    CHECK_I(ret, "verify_dataset_extension");
+    ret = verify_dataset_extension(fcpl_id, TRUE);
+    CHECK_I(ret, "verify_dataset_extension");
 
 
     /* All messages in lists */
     ret = H5Pset_shared_mesg_phase_change(fcpl_id, 100, 50);
     CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
 
-    ret = test_sohm_extend_dset_helper(fcpl_id, FALSE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
-    ret = test_sohm_extend_dset_helper(fcpl_id, TRUE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
+    ret = verify_dataset_extension(fcpl_id, FALSE);
+    CHECK_I(ret, "verify_dataset_extension");
+    ret = verify_dataset_extension(fcpl_id, TRUE);
+    CHECK_I(ret, "verify_dataset_extension");
 
 
     /* All messages in lists converted to B-trees */
     ret = H5Pset_shared_mesg_phase_change(fcpl_id, 1, 0);
     CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
 
-    ret = test_sohm_extend_dset_helper(fcpl_id, FALSE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
-    ret = test_sohm_extend_dset_helper(fcpl_id, TRUE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
+    ret = verify_dataset_extension(fcpl_id, FALSE);
+    CHECK_I(ret, "verify_dataset_extension");
+    ret = verify_dataset_extension(fcpl_id, TRUE);
+    CHECK_I(ret, "verify_dataset_extension");
 
 
     /* All messages in B-trees */
     ret = H5Pset_shared_mesg_phase_change(fcpl_id, 0, 0);
     CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
 
-    ret = test_sohm_extend_dset_helper(fcpl_id, FALSE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
-    ret = test_sohm_extend_dset_helper(fcpl_id, TRUE);
-    CHECK_I(ret, "test_sohm_extend_dset_helper");
+    ret = verify_dataset_extension(fcpl_id, FALSE);
+    CHECK_I(ret, "verify_dataset_extension");
+    ret = verify_dataset_extension(fcpl_id, TRUE);
+    CHECK_I(ret, "verify_dataset_extension");
 
     ret = H5Pclose(fcpl_id);
     CHECK_I(ret, "H5Pclose");
-}
+} /* test_sohm_extend_dset */
 
 
 /*-------------------------------------------------------------------------
@@ -3827,37 +3710,30 @@ test_sohm_external_dtype(void)
     unsigned x, i;
     herr_t ret;
 
+    MESSAGE(5, ("Testing shared external datatype\n"));
+
     fcpl = H5Pcreate(H5P_FILE_CREATE);
     CHECK_I(fcpl, "H5Pcreate");
-
-    /* Set up index values for sohm */
     ret = H5Pset_shared_mesg_nindexes(fcpl, TEST_NUM_INDEXES);
     CHECK_I(ret, "H5Pset_shared_mesg_nindexes");
-
-    for(x=0; x<TEST_NUM_INDEXES; ++x)
-    {
+    for(x=0; x<TEST_NUM_INDEXES; ++x) {
         ret = H5Pset_shared_mesg_index(fcpl, x, test_type_flags[x], test_minsizes[x]);
         CHECK_I(ret, "H5Pset_shared_mesg_index");
     }
-
     ret = H5Pset_shared_mesg_phase_change(fcpl, TEST_L2B, TEST_B2L);
     CHECK_I(ret, "H5Pset_shared_mesg_phase_change");
 
-    /* Create the data space */
     space = H5Screate_simple(2, dims, NULL);
     CHECK_I(space, "H5Screate_simple");
 
-    /* Create a data type for s1_t */
     s1_tid = H5Tcreate(H5T_COMPOUND, sizeof(s1_t));
     CHECK_I(s1_tid, "H5Tcreate");
-
     ret = H5Tinsert(s1_tid, "a", HOFFSET(s1_t,a), H5T_NATIVE_INT);
     CHECK_I(ret, "H5Tinsert");
-
     ret = H5Tinsert (s1_tid, "b", HOFFSET(s1_t,b), H5T_NATIVE_INT);
     CHECK_I(ret, "H5Tinsert");
 
-    /* Create the first file for this test */
+    /* Set up dataset in first file */
     file1 = H5Fcreate(FILENAME_SRC, H5F_ACC_TRUNC, fcpl, H5P_DEFAULT);
     CHECK_I(file1, "H5Fcreate");
 
@@ -3866,7 +3742,6 @@ test_sohm_external_dtype(void)
     CHECK(ret, FAIL, "H5F_get_sohm_mesg_count_test");
     VERIFY(dmsg_count, 0, "H5F_get_sohm_mesg_count_test");
 
-    /* Create data set */
     dataset1 = H5Dcreate2(file1, "dataset_1", s1_tid, space, H5P_DEFAULT, H5P_DEFAULT,
         H5P_DEFAULT);
     CHECK_I(dataset1, "H5Dcreate2");
@@ -3876,26 +3751,25 @@ test_sohm_external_dtype(void)
     CHECK(ret, FAIL, "H5F_get_sohm_mesg_count_test");
     VERIFY(dmsg_count, 1, "H5F_get_sohm_mesg_count_test");
 
-    /* Retieve the dataset's datatype */
     dset1_tid = H5Dget_type(dataset1);
     CHECK_I(dset1_tid, "H5Dget_type");
 
     /* Allocate space and initialize data */
     orig = (s1_t*)HDmalloc(NX * NY * sizeof(s1_t));
+    if (orig == NULL)
+        CHECK_I(-1, "HDmalloc");
     for(i=0; i<NX*NY; i++) {
         s_ptr = (s1_t*)orig + i;
         s_ptr->a = (int)(i * 3 + 1);
         s_ptr->b = (int)(i * 3 + 2);
     }
 
-    /* Write the data to the dataset1 */
     ret = H5Dwrite(dataset1, s1_tid, H5S_ALL, H5S_ALL, H5P_DEFAULT, orig);
     CHECK_I(ret, "H5Dwrite");
-
     ret = H5Dclose(dataset1);
     CHECK_I(ret, "H5Dclose");
 
-    /* Create the second file for this test */
+    /* Create dataset in second file using datatype from dataset in the first file */
     file2 = H5Fcreate(FILENAME_DST, H5F_ACC_TRUNC, fcpl, H5P_DEFAULT);
     CHECK_I(file2, "H5Fcreate");
 
@@ -3904,7 +3778,6 @@ test_sohm_external_dtype(void)
     CHECK(ret, FAIL, "H5F_get_sohm_mesg_count_test");
     VERIFY(dmsg_count, 0, "H5F_get_sohm_mesg_count_test");
 
-    /* Create a data set using the datatype of the dataset in the first file. */
     dataset2 = H5Dcreate2(file2, "dataset_2", dset1_tid, space, H5P_DEFAULT, H5P_DEFAULT,
         H5P_DEFAULT);
     CHECK_I(dataset2, "H5Dcreate2");
@@ -3914,30 +3787,25 @@ test_sohm_external_dtype(void)
     CHECK(ret, FAIL, "H5F_get_sohm_mesg_count_test");
     VERIFY(dmsg_count, 1, "H5F_get_sohm_mesg_count_test");
 
-    /* Write the data to the dataset2 */
     ret = H5Dwrite(dataset2, s1_tid, H5S_ALL, H5S_ALL, H5P_DEFAULT, orig);
     CHECK_I(ret, "H5Dwrite");
 
     ret = H5Dclose(dataset2);
     CHECK_I(ret, "H5Dclose");
 
-    /* Close file 1 and the dataset's datatype in file 1.  Verify that the datatype in
-     * file 2 is still accessible. */
     ret = H5Tclose(dset1_tid);
     CHECK_I(ret, "H5Tclose");
 
     ret = H5Fclose(file1);
     CHECK_I(ret, "H5Fclose");
 
-    /* Open the dataset in file 2 */
+    /* Verify that datatype details are still accessible by second file */
     dataset2 = H5Dopen2(file2, "dataset_2", H5P_DEFAULT);
     CHECK_I(dataset2, "H5Dopen2");
 
-    /* Retieve the dataset's datatype */
     dset2_tid = H5Dget_type(dataset2);
     CHECK_I(dset2_tid, "H5Dget_type");
 
-    /* Verify the datatype is compound */
     dtype_class = H5Tget_class(dset2_tid);
     VERIFY(dtype_class, H5T_COMPOUND, "H5Tget_class");
 
@@ -3947,21 +3815,17 @@ test_sohm_external_dtype(void)
     ret = H5Dclose(dataset2);
     CHECK_I(ret, "H5Dclose");
 
-    /* Finishing test and release resources */
+    /* Cleanup */
     ret = H5Sclose(space);
     CHECK_I(ret, "H5Sclose");
-
     ret = H5Tclose(s1_tid);
     CHECK_I(ret, "H5Tclose");
-
     ret = H5Pclose(fcpl);
     CHECK_I(ret, "H5Pclose");
-
     ret = H5Fclose(file2);
     CHECK_I(ret, "H5Fclose");
-
     HDfree(orig);
-}
+} /* test_sohm_external_dtype */
 
 
 /****************************************************************
@@ -3972,11 +3836,14 @@ test_sohm_external_dtype(void)
 void
 test_sohm(void)
 {
-    /* Output message about test being performed */
     MESSAGE(5, ("Testing Shared Object Header Messages\n"));
 
     test_sohm_fcpl();		/* Test SOHMs and file creation plists */
+    test_sohm_fcpl_errors();    /* Bogus H5P* calls for SOHMs */
     test_sohm_size1();          /* Tests the sizes of files with one SOHM */
+#if 0 /* TODO: REVEALS BUG TO BE FIXED - SEE JIRA HDFFV-10645 */
+    test_sohm_size_consistency_open_create();
+#endif /* Jira HDFFV-10645 */
     test_sohm_attrs();          /* Tests shared messages in attributes */
     test_sohm_size2(0);         /* Tests the sizes of files with multiple SOHMs */
     test_sohm_size2(1);         /* Tests the sizes of files with multiple
@@ -4012,5 +3879,5 @@ cleanup_sohm(void)
     remove(FILENAME);
     remove(FILENAME_SRC);
     remove(FILENAME_DST);
-}
+} /* cleanup_sohm */
 
diff --git a/test/tvlstr.c b/test/tvlstr.c
index 3315d68..2c552eb 100644
--- a/test/tvlstr.c
+++ b/test/tvlstr.c
@@ -23,10 +23,14 @@
 
 #define DATAFILE   "tvlstr.h5"
 #define DATAFILE2  "tvlstr2.h5"
+#define DATAFILE3  "sel2el.h5"
+
+#define DATASET    "1Darray"
 
 /* 1-D dataset with fixed dimensions */
 #define SPACE1_RANK    1
 #define SPACE1_DIM1    4
+#define NUMP           4
 
 #define VLSTR_TYPE      "vl_string_type"
 
@@ -846,6 +850,101 @@ static void test_vl_rewrite(void)
 } /* end test_vl_rewrite() */
 
 /****************************************************************
+ **
+ **  test_write_same_element():
+ **      Tests writing to the same element of VL string using
+ **      H5Sselect_element.
+ **
+ ****************************************************************/
+static void test_write_same_element(void)
+{
+    hid_t   file1, dataset1;
+    hid_t   mspace, fspace, dtype;
+    hsize_t fdim[] = {SPACE1_DIM1};
+    char *val[SPACE1_DIM1] = {"But", "reuniting", "is a", "great joy"};
+    hsize_t marray[] = {NUMP};
+    hsize_t coord[SPACE1_RANK][NUMP];
+    herr_t ret;
+
+    char *wdata[SPACE1_DIM1] = {"Parting", "is such a", "sweet", "sorrow."};
+
+    file1 = H5Fcreate(DATAFILE3, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(file1, FAIL, "H5Fcreate");
+
+    dtype = H5Tcopy(H5T_C_S1);
+    CHECK(dtype, FAIL, "H5Tcopy");
+
+    ret = H5Tset_size(dtype, H5T_VARIABLE);
+    CHECK(ret, FAIL, "H5Tset_size");
+
+    fspace = H5Screate_simple(SPACE1_RANK, fdim, NULL);
+    CHECK(fspace, FAIL, "H5Screate_simple");
+
+    dataset1 = H5Dcreate2(file1, DATASET, dtype, fspace, H5P_DEFAULT,
+                          H5P_DEFAULT, H5P_DEFAULT);
+    CHECK(dataset1, FAIL, "H5Dcreate2");
+
+    ret = H5Dwrite(dataset1, dtype, H5S_ALL, H5S_ALL, H5P_DEFAULT, wdata);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    ret = H5Dclose(dataset1);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    ret = H5Tclose(dtype);
+    CHECK(ret, FAIL, "H5Tclose");
+
+    ret = H5Sclose(fspace);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    ret = H5Fclose(file1);
+    CHECK(ret, FAIL, "H5Fclose");
+
+    /*
+     * Open the file.  Select the same points, write values to those point locations.
+     */
+    file1 = H5Fopen(DATAFILE3, H5F_ACC_RDWR, H5P_DEFAULT);
+    CHECK(file1, FAIL, "H5Fopen");
+
+    dataset1 = H5Dopen2(file1, DATASET, H5P_DEFAULT);
+    CHECK(dataset1, FAIL, "H5Dopen2");
+
+    fspace = H5Dget_space(dataset1);
+    CHECK(fspace, FAIL, "H5Dget_space");
+
+    dtype = H5Dget_type(dataset1);
+    CHECK(dtype, FAIL, "H5Dget_type");
+
+    mspace = H5Screate_simple(1, marray, NULL);
+    CHECK(mspace, FAIL, "H5Screate_simple");
+
+    coord[0][0] = 0;
+    coord[0][1] = 2;
+    coord[0][2] = 2;
+    coord[0][3] = 0;
+
+    ret = H5Sselect_elements(fspace, H5S_SELECT_SET, NUMP, (const hsize_t *)&coord);
+    CHECK(ret, FAIL, "H5Sselect_elements");
+
+    ret = H5Dwrite(dataset1, dtype, mspace, fspace, H5P_DEFAULT, val);
+    CHECK(ret, FAIL, "H5Dwrite");
+
+    ret = H5Tclose(dtype);
+    CHECK(ret, FAIL, "H5Tclose");
+
+    ret = H5Dclose(dataset1);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    ret = H5Sclose(fspace);
+    CHECK(ret, FAIL, "H5Dclose");
+
+    ret = H5Sclose(mspace);
+    CHECK(ret, FAIL, "H5Sclose");
+
+    ret = H5Fclose(file1);
+    CHECK(ret, FAIL, "H5Fclose");
+} /* test_write_same_element */
+
+/****************************************************************
 **
 **  test_vlstrings(): Main VL string testing routine.
 **
@@ -869,6 +968,8 @@ test_vlstrings(void)
 
     /* Test writing VL datasets in files with lots of unlinking */
     test_vl_rewrite();
+    /* Test writing to the same element more than once using H5Sselect_elements */
+    test_write_same_element();
 }   /* test_vlstrings() */
 
 
@@ -891,5 +992,6 @@ cleanup_vlstrings(void)
 {
     HDremove(DATAFILE);
     HDremove(DATAFILE2);
+    HDremove(DATAFILE3);
 }
 
diff --git a/test/use.h b/test/use.h
index 0885cc5..54d9b26 100644
--- a/test/use.h
+++ b/test/use.h
@@ -58,6 +58,6 @@ int setup_parameters(int argc, char * const argv[]);
 void show_parameters(void);
 void usage(const char *prog);
 int create_uc_file(void);
-int write_uc_file(hbool_t tosend);
+int write_uc_file(hbool_t tosend, hid_t fid);
 int read_uc_file(hbool_t towait);
 
diff --git a/test/use_append_chunk.c b/test/use_append_chunk.c
index 005eb51..4e8c672 100644
--- a/test/use_append_chunk.c
+++ b/test/use_append_chunk.c
@@ -124,10 +124,13 @@ main(int argc, char *argv[])
     int ret_value = 0;
     int child_ret_value;
     hbool_t send_wait = FALSE;
+    hid_t fapl = -1;    /* File access property list */
+    hid_t fid = -1;     /* File ID */
+    char *name;         /* Test file name */
 
     /* initialization */
     if (setup_parameters(argc, argv) < 0){
-	Hgoto_error(1);
+        Hgoto_error(1);
     }
 
     /* Determine the need to send/wait message file*/
@@ -145,20 +148,20 @@ main(int argc, char *argv[])
     /* Create file */
     /* ============*/
     if (UC_opts.launch != UC_READER){
-	printf("Creating skeleton data file for test...\n");
-	if (create_uc_file() < 0){
-	    fprintf(stderr, "***encounter error\n");
-	    Hgoto_error(1);
-	}else
-	    printf("File created.\n");
+        HDprintf("Creating skeleton data file for test...\n");
+        if (create_uc_file() < 0){
+            HDfprintf(stderr, "***encounter error\n");
+            Hgoto_error(1);
+        }else
+            HDprintf("File created.\n");
     }
 
     if (UC_opts.launch==UC_READWRITE){
-	/* fork process */
-	if((childpid = HDfork()) < 0) {
-	    HDperror("fork");
-	    Hgoto_error(1);
-	};
+        /* fork process */
+        if((childpid = HDfork()) < 0) {
+            HDperror("fork");
+            Hgoto_error(1);
+        };
     };
     mypid = HDgetpid();
 
@@ -166,53 +169,83 @@ main(int argc, char *argv[])
     /* launch reader */
     /* ============= */
     if (UC_opts.launch != UC_WRITER){
-	/* child process launch the reader */
-	if(0 == childpid) {
-	    printf("%d: launch reader process\n", mypid);
-	    if (read_uc_file(send_wait) < 0){
-		fprintf(stderr, "read_uc_file encountered error\n");
-		exit(1);
-	    }
-	    exit(0);
-	}
+        /* child process launch the reader */
+        if(0 == childpid) {
+            HDprintf("%d: launch reader process\n", mypid);
+            if (read_uc_file(send_wait) < 0){
+                HDfprintf(stderr, "read_uc_file encountered error\n");
+                HDexit(1);
+            }
+            HDexit(0);
+        }
     }
 
     /* ============= */
     /* launch writer */
     /* ============= */
     /* this process continues to launch the writer */
-    printf("%d: continue as the writer process\n", mypid);
-    if (write_uc_file(send_wait) < 0){
-	fprintf(stderr, "write_uc_file encountered error\n");
-	Hgoto_error(1);
+    HDprintf("%d: continue as the writer process\n", mypid);
+
+    name = UC_opts.filename;
+
+    /* Set file access proeprty list */
+    if((fapl = h5_fileaccess()) < 0)
+        Hgoto_error(1);
+
+    if(UC_opts.use_swmr)
+        if(H5Pset_libver_bounds(fapl, H5F_LIBVER_LATEST, H5F_LIBVER_LATEST) < 0)
+            Hgoto_error(1);
+
+    /* Open the file */
+    if((fid = H5Fopen(name, H5F_ACC_RDWR | (UC_opts.use_swmr ? H5F_ACC_SWMR_WRITE : 0), fapl)) < 0) {
+        HDfprintf(stderr, "H5Fopen failed\n");
+        Hgoto_error(1);
+    }
+
+    if(write_uc_file(send_wait, fid) < 0) {
+        HDfprintf(stderr, "write_uc_file encountered error\n");
+        Hgoto_error(1);
     }
 
     /* ================================================ */
     /* If readwrite, collect exit code of child process */
     /* ================================================ */
     if (UC_opts.launch == UC_READWRITE){
-	if ((tmppid = HDwaitpid(childpid, &child_status, child_wait_option)) < 0){
-	    HDperror("waitpid");
-	    Hgoto_error(1);
-	}
-	if (WIFEXITED(child_status)){
-	    if ((child_ret_value=WEXITSTATUS(child_status)) != 0){
-		printf("%d: child process exited with non-zero code (%d)\n",
-		    mypid, child_ret_value);
-		Hgoto_error(2);
-	    }
-	} else {
-	    printf("%d: child process terminated abnormally\n", mypid);
-	    Hgoto_error(2);
-	}
+        if ((tmppid = HDwaitpid(childpid, &child_status, child_wait_option)) < 0){
+            HDperror("waitpid");
+            Hgoto_error(1);
+        }
+
+        /* Close the file */
+        if(H5Fclose(fid) < 0) {
+            HDfprintf(stderr, "Failed to close file id\n");
+            Hgoto_error(1);
+        }
+
+        /* Close the property list */
+        if(H5Pclose(fapl) < 0) {
+            HDfprintf(stderr, "Failed to close the property list\n");
+            Hgoto_error(1);
+        }
+
+        if (WIFEXITED(child_status)){
+            if ((child_ret_value=WEXITSTATUS(child_status)) != 0){
+                HDprintf("%d: child process exited with non-zero code (%d)\n",
+                        mypid, child_ret_value);
+                Hgoto_error(2);
+            }
+         } else {
+                HDprintf("%d: child process terminated abnormally\n", mypid);
+                Hgoto_error(2);
+         }
     }
     
 done:
     /* Print result and exit */
     if (ret_value != 0){
-	printf("Error(s) encountered\n");
+        HDprintf("Error(s) encountered\n");
     }else{
-	printf("All passed\n");
+        HDprintf("All passed\n");
     }
 
     return(ret_value);
diff --git a/test/use_append_mchunks.c b/test/use_append_mchunks.c
index 9ee37cb..0414628 100644
--- a/test/use_append_mchunks.c
+++ b/test/use_append_mchunks.c
@@ -117,10 +117,13 @@ main(int argc, char *argv[])
     int ret_value = 0;
     int child_ret_value;
     hbool_t send_wait = 0;
+    hid_t fapl = -1;        /* File access property list */
+    hid_t fid = -1;         /* File ID */
+    char *name;             /* Test file name */
 
     /* initialization */
     if (setup_parameters(argc, argv) < 0){
-	Hgoto_error(1);
+        Hgoto_error(1);
     }
 
     /* Determine the need to send/wait message file*/
@@ -138,20 +141,20 @@ main(int argc, char *argv[])
     /* Create file */
     /* ============*/
     if (UC_opts.launch != UC_READER){
-	printf("Creating skeleton data file for test...\n");
+        HDprintf("Creating skeleton data file for test...\n");
 	if (create_uc_file() < 0){
-	    fprintf(stderr, "***encounter error\n");
+	    HDfprintf(stderr, "***encounter error\n");
 	    Hgoto_error(1);
 	}else
-	    printf("File created.\n");
+	    HDprintf("File created.\n");
     }
 
     if (UC_opts.launch==UC_READWRITE){
-	/* fork process */
-	if((childpid = fork()) < 0) {
-	    perror("fork");
-	    Hgoto_error(1);
-	};
+        /* fork process */
+        if((childpid = fork()) < 0) {
+            perror("fork");
+            Hgoto_error(1);
+        };
     };
     mypid = getpid();
 
@@ -159,53 +162,84 @@ main(int argc, char *argv[])
     /* launch reader */
     /* ============= */
     if (UC_opts.launch != UC_WRITER){
-	/* child process launch the reader */
-	if(0 == childpid) {
-	    printf("%d: launch reader process\n", mypid);
-	    if (read_uc_file(send_wait) < 0){
-		fprintf(stderr, "read_uc_file encountered error\n");
-		exit(1);
-	    }
-	    exit(0);
-	}
+        /* child process launch the reader */
+        if(0 == childpid) {
+            HDprintf("%d: launch reader process\n", mypid);
+            if (read_uc_file(send_wait) < 0){
+                HDfprintf(stderr, "read_uc_file encountered error\n");
+                HDexit(1);
+            }
+            HDexit(0);
+        }
     }
 
     /* ============= */
     /* launch writer */
     /* ============= */
     /* this process continues to launch the writer */
-    printf("%d: continue as the writer process\n", mypid);
-    if (write_uc_file(send_wait) < 0){
-	fprintf(stderr, "write_uc_file encountered error\n");
-	Hgoto_error(1);
+    HDprintf("%d: continue as the writer process\n", mypid);
+
+    name = UC_opts.filename;
+
+    /* Set the file access property list */
+    if((fapl = h5_fileaccess()) < 0)
+        Hgoto_error(1);
+
+    if(UC_opts.use_swmr)
+        if(H5Pset_libver_bounds(fapl, H5F_LIBVER_LATEST, H5F_LIBVER_LATEST) < 0)
+            Hgoto_error(1);
+
+    /* Open the file */
+    if((fid = H5Fopen(name, H5F_ACC_RDWR | (UC_opts.use_swmr ? H5F_ACC_SWMR_WRITE : 0), fapl)) < 0) {
+        HDfprintf(stderr, "H5Fopen failed\n");
+        Hgoto_error(1);
+    }
+
+    if(write_uc_file(send_wait, fid) < 0) {
+        HDfprintf(stderr, "write_uc_file encountered error\n");
+        Hgoto_error(1);
     }
 
+
     /* ================================================ */
     /* If readwrite, collect exit code of child process */
     /* ================================================ */
     if (UC_opts.launch == UC_READWRITE){
-	if ((tmppid = waitpid(childpid, &child_status, child_wait_option)) < 0){
-	    perror("waitpid");
-	    Hgoto_error(1);
-	}
-	if (WIFEXITED(child_status)){
-	    if ((child_ret_value=WEXITSTATUS(child_status)) != 0){
-		printf("%d: child process exited with non-zero code (%d)\n",
-		    mypid, child_ret_value);
-		Hgoto_error(2);
-	    }
-	} else {
-	    printf("%d: child process terminated abnormally\n", mypid);
-	    Hgoto_error(2);
-	}
+        if ((tmppid = waitpid(childpid, &child_status, child_wait_option)) < 0){
+            perror("waitpid");
+            Hgoto_error(1);
+        }
+
+        /* Close the file  */
+        if(H5Fclose(fid) < 0) {
+            HDfprintf(stderr, "Failed to close file id\n");
+            Hgoto_error(1);
+        }
+
+        /* Close the property list */
+        if(H5Pclose(fapl) < 0) {
+            HDfprintf(stderr, "Failed to close the property list\n");
+            Hgoto_error(1);
+        }
+
+        if (WIFEXITED(child_status)){
+            if ((child_ret_value=WEXITSTATUS(child_status)) != 0){
+                HDprintf("%d: child process exited with non-zero code (%d)\n",
+                    mypid, child_ret_value);
+                Hgoto_error(1);
+            }
+        } else {
+            HDprintf("%d: child process terminated abnormally\n", mypid);
+            Hgoto_error(2);
+        }
     }
     
 done:
     /* Print result and exit */
     if (ret_value != 0){
-	printf("Error(s) encountered\n");
+        HDprintf("Error(s) encountered\n");
     }else{
-	printf("All passed\n");
+        HDprintf("All passed\n");
     }
 
     return(ret_value);
diff --git a/test/use_common.c b/test/use_common.c
index 5aa6692..3ecb2e1 100644
--- a/test/use_common.c
+++ b/test/use_common.c
@@ -252,13 +252,10 @@ int create_uc_file(void)
  *
  * Return: 0 succeed; -1 fail.
  */
-int write_uc_file(hbool_t tosend)
+int write_uc_file(hbool_t tosend, hid_t fid)
 {
-    hid_t	fid;          /* File ID for new HDF5 file */
     hid_t	dsid;         /* dataset ID */
-    hid_t       fapl;         /* File access property list */
     hid_t	dcpl;         /* Dataset creation property list */
-    char	*name;
     UC_CTYPE	*buffer, *bufptr;	/* data buffer */
     hsize_t	cz=UC_opts.chunksize;		/* Chunk size */
     hid_t	f_sid;	    /* dataset file space id */
@@ -270,19 +267,6 @@ int write_uc_file(hbool_t tosend)
     hsize_t	start[3] = {0,0,0}, count[3];    /* Hyperslab selection values */
     hsize_t     i, j, k;
 
-    name = UC_opts.filename;
-
-    /* Open the file */
-    if((fapl = h5_fileaccess()) < 0)
-        return -1;
-    if(UC_opts.use_swmr)
-        if(H5Pset_libver_bounds(fapl, H5F_LIBVER_LATEST, H5F_LIBVER_LATEST) < 0)
-            return -1;
-    if((fid = H5Fopen(name, H5F_ACC_RDWR | (UC_opts.use_swmr ? H5F_ACC_SWMR_WRITE : 0), fapl)) < 0){
-	fprintf(stderr, "H5Fopen failed\n");
-        return -1;
-    }
-
     if(tosend)
         /* Send a message that H5Fopen is complete--releasing the file lock */
         h5_send_message(WRITER_MESSAGE, NULL, NULL);
@@ -427,14 +411,6 @@ int write_uc_file(hbool_t tosend)
 	fprintf(stderr, "Failed to close file space\n");
 	return -1;
     }
-    if (H5Pclose(fapl) < 0){
-	fprintf(stderr, "Failed to property list\n");
-	return -1;
-    }
-    if (H5Fclose(fid) < 0){
-	fprintf(stderr, "Failed to close file id\n");
-	return -1;
-    }
 
     return 0;
 }
@@ -471,7 +447,7 @@ int read_uc_file(hbool_t towait)
 
     /* Before reading, wait for the message that H5Fopen is complete--file lock is released */
     if(towait && h5_wait_message(WRITER_MESSAGE) < 0) {
-        fprintf(stderr, "Cannot find writer message file...failed\n");
+        HDfprintf(stderr, "Cannot find writer message file...failed\n");
         return -1;
     }
 
@@ -481,19 +457,19 @@ int read_uc_file(hbool_t towait)
     if((fapl = h5_fileaccess()) < 0)
         return -1;
     if((fid = H5Fopen(name, H5F_ACC_RDONLY | (UC_opts.use_swmr ? H5F_ACC_SWMR_READ : 0), fapl)) < 0){
-	fprintf(stderr, "H5Fopen failed\n");
+        HDfprintf(stderr, "H5Fopen failed\n");
         return -1;
     }
     if (H5Pclose(fapl) < 0){
-	    fprintf(stderr, "Failed to property list\n");
+	    HDfprintf(stderr, "Failed to property list\n");
 	    return -1;
     }
 
 
     /* Open the dataset of the program name */
     if((dsid = H5Dopen2(fid, progname_g, H5P_DEFAULT)) < 0){
-	fprintf(stderr, "H5Dopen2 failed\n");
-	return -1;
+        HDfprintf(stderr, "H5Dopen2 failed\n");
+        return -1;
     }
 
     /* allocate space for data buffer 1 X dims[1] X dims[2] of UC_CTYPE */
@@ -501,8 +477,8 @@ int read_uc_file(hbool_t towait)
     memdims[1] = UC_opts.dims[1];
     memdims[2] = UC_opts.dims[2];
     if ((buffer=(UC_CTYPE*)HDmalloc((size_t)memdims[1]*(size_t)memdims[2]*sizeof(UC_CTYPE)))==NULL) {
-	fprintf(stderr, "malloc: failed\n");
-	return -1;
+        HDfprintf(stderr, "malloc: failed\n");
+        return -1;
     };
 
     /*
@@ -512,31 +488,31 @@ int read_uc_file(hbool_t towait)
     f_sid = H5Dget_space(dsid);    /* Get filespace handle first. */
     rank  = H5Sget_simple_extent_ndims(f_sid);
     if (rank != UC_RANK){
-	fprintf(stderr, "rank(%d) of dataset does not match\n", rank);
-	return -1;
+        HDfprintf(stderr, "rank(%d) of dataset does not match\n", rank);
+        return -1;
     }
     if (H5Sget_simple_extent_dims(f_sid, dims, NULL) < 0){
-	fprintf(stderr, "H5Sget_simple_extent_dims got error\n");
-	return -1;
+        HDfprintf(stderr, "H5Sget_simple_extent_dims got error\n");
+        return -1;
     }
-    printf("dataset rank %d, dimensions %llu x %llu x %llu\n",
-	   rank, (unsigned long long)(dims[0]), (unsigned long long)(dims[1]),
-           (unsigned long long)(dims[2]));
+    HDprintf("dataset rank %d, dimensions %llu x %llu x %llu\n",
+            rank, (unsigned long long)(dims[0]), (unsigned long long)(dims[1]),
+            (unsigned long long)(dims[2]));
     /* verify that file space dims are as expected and are consistent with memory space dims */
     if (dims[1] != memdims[1] || dims[2] != memdims[2]){
-	fprintf(stderr, "dataset dimension is not as expected. Got dims=(%llu,%llu,%llu)\n",
-	    (unsigned long long)dims[0], (unsigned long long)dims[1],
+        HDfprintf(stderr, "dataset dimension is not as expected. Got dims=(%llu,%llu,%llu)\n",
+            (unsigned long long)dims[0], (unsigned long long)dims[1],
             (unsigned long long)dims[2]);
-	fprintf(stderr, "But memdims=(%llu,%llu,%llu)\n",
-	    (unsigned long long)memdims[0], (unsigned long long)memdims[1], 
+        HDfprintf(stderr, "But memdims=(%llu,%llu,%llu)\n",
+            (unsigned long long)memdims[0], (unsigned long long)memdims[1], 
             (unsigned long long)memdims[2]);
-	return -1;
+        return -1;
     }
     
     /* setup mem-space for buffer */
     if ((m_sid=H5Screate_simple(rank, memdims, NULL))<0){
-	fprintf(stderr, "H5Screate_simple for memory failed\n");
-	return -1;
+        HDfprintf(stderr, "H5Screate_simple for memory failed\n");
+        return -1;
     };
 
     /* Read 1 plane at a time whenever the dataset grows larger
@@ -550,22 +526,22 @@ int read_uc_file(hbool_t towait)
 	/* print progress message according to if new planes are availalbe */
 	if (nplane_old < dims[0]) {
 	    if (nonewplane){
-		/* end the previous message */
-		printf("\n");
-		nonewplane=0;
+            /* end the previous message */
+            HDprintf("\n");
+            nonewplane=0;
 	    }
-	    printf("reading planes %llu to %llu\n", (unsigned long long)nplane_old, 
+	    HDprintf("reading planes %llu to %llu\n", (unsigned long long)nplane_old, 
                 (unsigned long long)dims[0]);
 	}else{
 	    if (nonewplane){
-		printf(".");
+            HDprintf(".");
 		if (nonewplane>=30){
-		    fprintf(stderr, "waited too long for new plane, quit.\n");
+		    HDfprintf(stderr, "waited too long for new plane, quit.\n");
 		    return -1;
 		}
 	    }else{
-		/* print mesg only the first time; dots still no new plane */
-		printf("no new planes to read ");
+            /* print mesg only the first time; dots still no new plane */
+            HDprintf("no new planes to read ");
 	    }
 	    nonewplane++;
 	    /* pause for a second */
@@ -575,41 +551,41 @@ int read_uc_file(hbool_t towait)
 	    /* read planes between last old nplanes and current extent */
 	    /* Get the dataset's dataspace */
 	    if((f_sid = H5Dget_space(dsid)) < 0){
-		fprintf(stderr, "H5Dget_space failed\n");
-		return -1;
+            HDfprintf(stderr, "H5Dget_space failed\n");
+            return -1;
 	    }
 
 	    start[0]=nplane;
 	    /* Choose the next plane to read */
 	    if(H5Sselect_hyperslab(f_sid, H5S_SELECT_SET, start, NULL, count, NULL) < 0){
-		fprintf(stderr, "H5Sselect_hyperslab failed\n");
-		return -1;
+            HDfprintf(stderr, "H5Sselect_hyperslab failed\n");
+            return -1;
 	    }
 
 	    /* Read the plane from the dataset */
 	    if(H5Dread(dsid, UC_DATATYPE, m_sid, f_sid, H5P_DEFAULT, buffer) < 0){
-		fprintf(stderr, "H5Dread failed\n");
-		return -1;
+            HDfprintf(stderr, "H5Dread failed\n");
+            return -1;
 	    }
 
 	    /* compare read data with expected data value which is nplane */
 	    bufptr = buffer;
 	    nerrs=0;
 	    for (j=0; j<dims[1]; j++){
-		for (k=0; k<dims[2]; k++){
-		    if ((hsize_t)*bufptr++ != nplane){
-			if (++nerrs < ErrorReportMax){
-			    fprintf(stderr,
-				"found error %llu plane(%llu,%llu), expected %llu, got %d\n",
-				(unsigned long long)nplane, (unsigned long long)j, 
-                                (unsigned long long)k, (unsigned long long)nplane, (int)*(bufptr-1));
-			}
-		    }
-		}
+            for (k=0; k<dims[2]; k++){
+                if ((hsize_t)*bufptr++ != nplane){
+                    if (++nerrs < ErrorReportMax){
+                        HDfprintf(stderr,
+                            "found error %llu plane(%llu,%llu), expected %llu, got %d\n",
+                            (unsigned long long)nplane, (unsigned long long)j, 
+                            (unsigned long long)k, (unsigned long long)nplane, (int)*(bufptr-1));
+                    }
+                }
+            }
 	    }
 	    if (nerrs){
-		nreadererr++;
-		fprintf(stderr, "found %d unexpected values in plane %llu\n", nerrs, 
+            nreadererr++;
+            HDfprintf(stderr, "found %d unexpected values in plane %llu\n", nerrs, 
                     (unsigned long long)nplane);
 	    }
 	}
@@ -620,19 +596,19 @@ int read_uc_file(hbool_t towait)
 #if 0
 	/* close dsid and file, then reopen them */
 	if (H5Dclose(dsid) < 0){
-	    fprintf(stderr, "H5Dclose failed\n");
+	    HDfprintf(stderr, "H5Dclose failed\n");
 	    return -1;
 	}
 	if (H5Fclose(fid) < 0){
-	    fprintf(stderr, "H5Fclose failed\n");
+	    HDfprintf(stderr, "H5Fclose failed\n");
 	    return -1;
 	}
 	if((fid = H5Fopen(name, H5F_ACC_RDONLY | (UC_opts.use_swmr ? H5F_ACC_SWMR_READ : 0), H5P_DEFAULT)) < 0){
-	    fprintf(stderr, "H5Fopen failed\n");
+	    HDfprintf(stderr, "H5Fopen failed\n");
 	    return -1;
 	}
 	if((dsid = H5Dopen2(fid, progname_g, H5P_DEFAULT)) < 0){
-	    fprintf(stderr, "H5Dopen2 failed\n");
+	    HDfprintf(stderr, "H5Dopen2 failed\n");
 	    return -1;
 	}
 #else
@@ -640,16 +616,22 @@ int read_uc_file(hbool_t towait)
 #endif
 	f_sid = H5Dget_space(dsid);    /* Get filespace handle first. */
 	if (H5Sget_simple_extent_dims(f_sid, dims, NULL) < 0){
-	    fprintf(stderr, "H5Sget_simple_extent_dims got error\n");
+	    HDfprintf(stderr, "H5Sget_simple_extent_dims got error\n");
 	    return -1;
 	}
     }
 
+    /* Close the file */
+    if(H5Fclose(fid) < 0) {
+        HDfprintf(stderr, "H5Fclose failed\n");
+        return -1;
+    }
+
     if (nreadererr)
-	return -1;
+        return -1;
     else
-	return 0;
-}
+        return 0;
+} /* read_uc_file() */
 
 #endif /* H5_HAVE_FORK */
author	Larry Knox <lrknox@hdfgroup.org>	2019-02-28 21:24:02 (GMT)
committer	Larry Knox <lrknox@hdfgroup.org>	2019-02-28 21:24:02 (GMT)
commit	646fc294078f560fc9bef784cb1c4e27cdc51f5b (patch)
tree	21502062cfc4ab6410f6d81de11e28c1523e85bd /test
parent	5eef94f83f4875b64ffe7f9cea05d965bddbd802 (diff)
parent	6819c11508b0610f222fe3bfe8a19f637bf4319c (diff)
download	hdf5-hdf5-1_10_5.zip hdf5-hdf5-1_10_5.tar.gz hdf5-hdf5-1_10_5.tar.bz2