Most changes for fixing post open issues

1 files changed, 255 insertions, 27 deletions

diff --git a/tools/test/h5diff/testh5diff.sh.in b/tools/test/h5diff/testh5diff.sh.in
index bd27dd0..f727c7a 100644
--- a/tools/test/h5diff/testh5diff.sh.in
+++ b/tools/test/h5diff/testh5diff.sh.in
@@ -35,6 +35,8 @@ EXIT_FAILURE=1
 
 H5DIFF=../../src/h5diff/h5diff               # The tool name
 H5DIFF_BIN=`pwd`/$H5DIFF    # The path of the tool binary
+VDS_CHECK_COMPAT_VOL=../../../utils/vds_check_compat_vol # The vds_check_compat_vol tool name
+VDS_CHECK_COMPAT_VOL_BIN=`pwd`/$VDS_CHECK_COMPAT_VOL # The path of the vds_check_compat_vol tool binary
 
 RM='rm -rf'
 CMP='cmp -s'
@@ -595,6 +597,13 @@ COPY_TESTFILES_TO_TESTDIR
 # second copy of tvlstr.h5
 $CP -f $SRC_TOOLS_TESTFILES/tvlstr.h5 $TESTDIR/tvlstr2.h5
 
+# Check to see if the VOL connector specified by the HDF5_VOL_CONNECTOR
+# environment variable supports virtual datasets (and external links)
+#
+# Note: Depends on vds_check_compat_vol tool from $(topdir)/utils
+$VDS_CHECK_COMPAT_VOL_BIN
+COMPAT_VOL=$?
+
 # ############################################################################
 # # Common usage
 # ############################################################################
@@ -966,22 +975,70 @@ TOOLTEST h5diff_402.txt --follow-symlinks -v h5diff_softlinks.h5 h5diff_softlink
 TOOLTEST h5diff_403.txt --follow-symlinks -v h5diff_softlinks.h5 h5diff_softlinks.h5 /softlink_dset1_1 /softlink_dset2
 
 # extlink vs extlink (FILE)"
-TOOLTEST h5diff_404.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_404.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # extlink vs dset"
-TOOLTEST h5diff_405.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_trg.h5 /ext_link_dset1 /target_group2/x_dset
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_405.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_trg.h5 /ext_link_dset1 /target_group2/x_dset"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # dset vs extlink"
-TOOLTEST h5diff_406.txt --follow-symlinks -v h5diff_extlink_trg.h5 h5diff_extlink_src.h5 /target_group2/x_dset /ext_link_dset1
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_406.txt --follow-symlinks -v h5diff_extlink_trg.h5 h5diff_extlink_src.h5 /target_group2/x_dset /ext_link_dset1"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # extlink vs extlink"
-TOOLTEST h5diff_407.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_dset1 /ext_link_dset2
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_407.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_dset1 /ext_link_dset2"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # softlink vs extlink"
-TOOLTEST h5diff_408.txt --follow-symlinks -v h5diff_softlinks.h5 h5diff_extlink_src.h5 /softlink_dset1_1 /ext_link_dset2
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_408.txt --follow-symlinks -v h5diff_softlinks.h5 h5diff_extlink_src.h5 /softlink_dset1_1 /ext_link_dset2"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # extlink vs softlink "
-TOOLTEST h5diff_409.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_softlinks.h5 /ext_link_dset2 /softlink_dset1_1
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_409.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_softlinks.h5 /ext_link_dset2 /softlink_dset1_1"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # linked_softlink vs linked_softlink (FILE)"
 TOOLTEST h5diff_410.txt --follow-symlinks -v h5diff_linked_softlink.h5 h5diff_linked_softlink.h5
@@ -1011,31 +1068,95 @@ TOOLTEST h5diff_417.txt --follow-symlinks -v h5diff_softlinks.h5 h5diff_softlink
 TOOLTEST h5diff_418.txt --follow-symlinks -v h5diff_softlinks.h5 h5diff_softlinks.h5 /softlink_dset2 /softlink_noexist
 
 # non-exist-extlink_file vs extlink"
-TOOLTEST h5diff_419.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_noexist2 /ext_link_dset2
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_419.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_noexist2 /ext_link_dset2"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # exlink vs non-exist-extlink_file"
-TOOLTEST h5diff_420.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_dset2 /ext_link_noexist2
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_420.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_dset2 /ext_link_noexist2"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # extlink vs non-exist-extlink_obj"
-TOOLTEST h5diff_421.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_dset2 /ext_link_noexist1
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_421.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_dset2 /ext_link_noexist1"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # non-exist-extlink_obj vs extlink"
-TOOLTEST h5diff_422.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_noexist1 /ext_link_dset2
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_422.txt --follow-symlinks -v h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_noexist1 /ext_link_dset2"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # extlink_to_softlink_to_dset1 vs dset2"
-TOOLTEST h5diff_423.txt --follow-symlinks -v h5diff_ext2softlink_src.h5 h5diff_ext2softlink_trg.h5 /ext_link_to_slink1 /dset2
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_423.txt --follow-symlinks -v h5diff_ext2softlink_src.h5 h5diff_ext2softlink_trg.h5 /ext_link_to_slink1 /dset2"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # dset2 vs extlink_to_softlink_to_dset1"
-TOOLTEST h5diff_424.txt --follow-symlinks -v h5diff_ext2softlink_trg.h5 h5diff_ext2softlink_src.h5 /dset2 /ext_link_to_slink1
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_424.txt --follow-symlinks -v h5diff_ext2softlink_trg.h5 h5diff_ext2softlink_src.h5 /dset2 /ext_link_to_slink1"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # extlink_to_softlink_to_dset1 vs extlink_to_softlink_to_dset2"
-TOOLTEST h5diff_425.txt --follow-symlinks -v h5diff_ext2softlink_src.h5 h5diff_ext2softlink_src.h5 /ext_link_to_slink1 /ext_link_to_slink2
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_425.txt --follow-symlinks -v h5diff_ext2softlink_src.h5 h5diff_ext2softlink_src.h5 /ext_link_to_slink1 /ext_link_to_slink2"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # ##############################################################################
 # # Dangling links compare (--follow-symlinks and --no-dangling-links)
 # ##############################################################################
 # dangling links --follow-symlinks (FILE to FILE)
-TOOLTEST h5diff_450.txt  --follow-symlinks -v h5diff_danglelinks1.h5 h5diff_danglelinks2.h5
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_450.txt  --follow-symlinks -v h5diff_danglelinks1.h5 h5diff_danglelinks2.h5"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # dangling links --follow-symlinks and --no-dangling-links (FILE to FILE)
 TOOLTEST h5diff_451.txt  --follow-symlinks -v --no-dangling-links  h5diff_danglelinks1.h5 h5diff_danglelinks2.h5
@@ -1053,13 +1174,37 @@ TOOLTEST h5diff_454.txt  --follow-symlinks -v --no-dangling-links  h5diff_softli
 TOOLTEST h5diff_455.txt  --follow-symlinks -v --no-dangling-links  h5diff_softlinks.h5 h5diff_softlinks.h5 /softlink_noexist /softlink_noexist
 
 # dangling link found for ext links (FILE to FILE)
-TOOLTEST h5diff_456.txt  --follow-symlinks -v --no-dangling-links  h5diff_extlink_src.h5 h5diff_extlink_src.h5
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_456.txt  --follow-symlinks -v --no-dangling-links  h5diff_extlink_src.h5 h5diff_extlink_src.h5"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # dangling link found for ext links (obj to obj). target file exist
-TOOLTEST h5diff_457.txt  --follow-symlinks -v --no-dangling-links  h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_dset1 /ext_link_noexist1
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_457.txt  --follow-symlinks -v --no-dangling-links  h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_dset1 /ext_link_noexist1"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # dangling link found for ext links (obj to obj). target file NOT exist
-TOOLTEST h5diff_458.txt  --follow-symlinks -v --no-dangling-links  h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_dset1 /ext_link_noexist2
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_458.txt  --follow-symlinks -v --no-dangling-links  h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_dset1 /ext_link_noexist2"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # dangling link found for ext links (obj to obj). Both dangle links
 TOOLTEST h5diff_459.txt  --follow-symlinks -v --no-dangling-links  h5diff_extlink_src.h5 h5diff_extlink_src.h5 /ext_link_noexist1 /ext_link_noexist2
@@ -1075,7 +1220,15 @@ TOOLTEST h5diff_467.txt -v --follow-symlinks h5diff_danglelinks1.h5 h5diff_dangl
 # ext dangling vs. ext dangling
 TOOLTEST h5diff_468.txt -v --follow-symlinks h5diff_danglelinks1.h5 h5diff_danglelinks2.h5 /ext_link4
 # ext link vs. ext dangling
-TOOLTEST h5diff_469.txt -v --follow-symlinks h5diff_danglelinks1.h5 h5diff_danglelinks2.h5 /ext_link2
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_469.txt -v --follow-symlinks h5diff_danglelinks1.h5 h5diff_danglelinks2.h5 /ext_link2"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 #----------------------------------------
 # dangling links without follow symlink
@@ -1093,7 +1246,15 @@ TOOLTEST h5diff_475.txt -v h5diff_danglelinks1.h5 h5diff_danglelinks2.h5 /ext_li
 # ##############################################################################
 # root
 TOOLTEST h5diff_500.txt -v h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 / /
-TOOLTEST h5diff_501.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 / /
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_501.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 / /"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # root vs group
 TOOLTEST h5diff_502.txt -v h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 / /grp1/grp2/grp3
@@ -1110,19 +1271,51 @@ TOOLTEST h5diff_506.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_r
 
 # groups vs ext-link
 TOOLTEST h5diff_507.txt -v h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /grp1 /elink_grp1
-TOOLTEST h5diff_508.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /grp1 /elink_grp1
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_508.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /grp1 /elink_grp1"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # soft-link vs ext-link
 TOOLTEST h5diff_509.txt -v h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /slink_grp1 /elink_grp1
-TOOLTEST h5diff_510.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /slink_grp1 /elink_grp1
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_510.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /slink_grp1 /elink_grp1"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # circled ext links
 TOOLTEST h5diff_511.txt -v h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /grp10 /grp11
-TOOLTEST h5diff_512.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /grp10 /grp11
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_512.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /grp10 /grp11"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # circled soft2ext-link vs soft2ext-link
 TOOLTEST h5diff_513.txt -v h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /slink_grp10 /slink_grp11
-TOOLTEST h5diff_514.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /slink_grp10 /slink_grp11
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_514.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_recurse2.h5 /slink_grp10 /slink_grp11"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 ###############################################################################
 # Test for group recursive diff via multi-linked external links
@@ -1131,10 +1324,26 @@ TOOLTEST h5diff_514.txt -v --follow-symlinks h5diff_grp_recurse1.h5 h5diff_grp_r
 ###############################################################################
 # file vs file
 TOOLTEST h5diff_515.txt -v h5diff_grp_recurse_ext1.h5 h5diff_grp_recurse_ext2-1.h5
-TOOLTEST h5diff_516.txt -v --follow-symlinks h5diff_grp_recurse_ext1.h5 h5diff_grp_recurse_ext2-1.h5
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_516.txt -v --follow-symlinks h5diff_grp_recurse_ext1.h5 h5diff_grp_recurse_ext2-1.h5"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 # group vs group
 TOOLTEST h5diff_517.txt -v h5diff_grp_recurse_ext1.h5 h5diff_grp_recurse_ext2-1.h5 /g1
-TOOLTEST h5diff_518.txt -v --follow-symlinks h5diff_grp_recurse_ext1.h5 h5diff_grp_recurse_ext2-1.h5 /g1
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_518.txt -v --follow-symlinks h5diff_grp_recurse_ext1.h5 h5diff_grp_recurse_ext2-1.h5 /g1"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support external links."
+fi
 
 # ##############################################################################
 # # Exclude objects (--exclude-path)
@@ -1210,9 +1419,28 @@ TOOLTEST h5diff_801.txt -v h5diff_dset1.h5 h5diff_dset3.h5 /g1/array /g1/array
 # ##############################################################################
 # VDS tests
 # ##############################################################################
-TOOLTEST h5diff_v1.txt -v 1_vds.h5 2_vds.h5
+
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_v1.txt -v 1_vds.h5 2_vds.h5"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support virtual datasets."
+fi
+
 TOOLTEST h5diff_v2.txt -r 1_vds.h5 2_vds.h5
-TOOLTEST h5diff_v3.txt -c 1_vds.h5 2_vds.h5
+
+# Note: Requires VOL connector that supports external links
+ARGS="h5diff_v3.txt -c 1_vds.h5 2_vds.h5"
+if [ $COMPAT_VOL -eq $EXIT_SUCCESS ]; then
+    TOOLTEST $ARGS
+else
+    SKIP $ARGS
+    echo "    The VOL connector specified by the HDF5_VOL_CONNECTOR environment"
+    echo "    variable does not support virtual datasets."
+fi
 
 
 # ##############################################################################