[svn-r23760] Implement SWMR-5:

Implemented use case 1.8 program--SWRM read/write multiple chunks at a time.

test/use_append_mchunks.c:
    The program.
test/Makefile.am:
test/Makefile.in:
    Added program use_append_mchunks.
test/test_usecases.sh.in:
    Added simple tests for use_append_mchunks.
MANIFEST:
    Updated for new file.

Tested: h5committest, except cmake, passed. Hand tested in Koala for various options.

5 files changed, 602 insertions, 8 deletions

diff --git a/MANIFEST b/MANIFEST
index 954ee68..a0be685 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -1124,6 +1124,7 @@
 ./test/tvltypes.c
 ./test/unlink.c
 ./test/use_append_chunk.c
+./test/use_append_mchunks.c
 ./test/use_common.c
 ./test/use.h
 ./test/vfd.c
diff --git a/test/Makefile.am b/test/Makefile.am
index 03241c1..397d20f 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -51,7 +51,7 @@ TEST_PROG= testhdf5 lheap ohdr stab gheap cache cache_api cache_tagging \
 
 bin_PROGRAMS=swmr_generator swmr_reader swmr_writer swmr_remove_reader \
     swmr_remove_writer swmr_addrem_writer swmr_sparse_reader swmr_sparse_writer \
-    use_append_chunk
+    use_append_chunk use_append_mchunks
 
 # List programs to be built when testing here. error_test and err_compat are
 # built at the same time as the other tests, but executed by testerror.sh.
@@ -159,7 +159,7 @@ CHECK_CLEANFILES+=accum.h5 cmpd_dset.h5 compact_dataset.h5 dataset.h5 \
     new_multi_file_v16-r.h5 new_multi_file_v16-s.h5                  \
     split_get_file_image_test-m.h5 split_get_file_image_test-r.h5    \
     file_image_core_test.h5.copy                                     \
-    swmr_data.h5 use_append_chunk.h5                                       \
+    swmr_data.h5 use_append_chunk.h5 use_append_mchunks.h5           \
     flushrefresh.h5 flushrefresh_VERIFICATION_START                  \
     flushrefresh_VERIFICATION_CHECKPOINT1 flushrefresh_VERIFICATION_CHECKPOINT2 \
     flushrefresh_VERIFICATION_DONE
@@ -172,6 +172,7 @@ testhdf5_SOURCES=testhdf5.c tarray.c tattr.c tchecksum.c tconfig.c tfile.c \
 
 # Sources for Use Cases
 use_append_chunk_SOURCES=use_append_chunk.c use_common.c
+use_append_mchunks_SOURCES=use_append_mchunks.c use_common.c
 
 # Temporary files.
 DISTCLEANFILES=testerror.sh testlibinfo.sh testcheck_version.sh testlinks_env.sh test_plugin.sh \
diff --git a/test/Makefile.in b/test/Makefile.in
index b3c9653..b45746f 100644
--- a/test/Makefile.in
+++ b/test/Makefile.in
@@ -83,7 +83,7 @@ bin_PROGRAMS = 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) \
-	use_append_chunk$(EXEEXT)
+	use_append_chunk$(EXEEXT) use_append_mchunks$(EXEEXT)
 check_PROGRAMS = $(am__EXEEXT_1) error_test$(EXEEXT) \
 	err_compat$(EXEEXT) tcheck_version$(EXEEXT) testmeta$(EXEEXT) \
 	links_env$(EXEEXT) flushrefresh$(EXEEXT) $(am__EXEEXT_2)
@@ -538,6 +538,11 @@ am_use_append_chunk_OBJECTS = use_append_chunk.$(OBJEXT) \
 use_append_chunk_OBJECTS = $(am_use_append_chunk_OBJECTS)
 use_append_chunk_LDADD = $(LDADD)
 use_append_chunk_DEPENDENCIES = libh5test.la $(LIBHDF5)
+am_use_append_mchunks_OBJECTS = use_append_mchunks.$(OBJEXT) \
+	use_common.$(OBJEXT)
+use_append_mchunks_OBJECTS = $(am_use_append_mchunks_OBJECTS)
+use_append_mchunks_LDADD = $(LDADD)
+use_append_mchunks_DEPENDENCIES = libh5test.la $(LIBHDF5)
 vfd_SOURCES = vfd.c
 vfd_OBJECTS = vfd.$(OBJEXT)
 vfd_LDADD = $(LDADD)
@@ -596,7 +601,8 @@ SOURCES = $(libdynlib1_la_SOURCES) $(libdynlib2_la_SOURCES) \
 	swmr_generator.c swmr_reader.c swmr_remove_reader.c \
 	swmr_remove_writer.c swmr_sparse_reader.c swmr_sparse_writer.c \
 	swmr_writer.c tcheck_version.c $(testhdf5_SOURCES) testmeta.c \
-	$(ttsafe_SOURCES) unlink.c $(use_append_chunk_SOURCES) vfd.c
+	$(ttsafe_SOURCES) unlink.c $(use_append_chunk_SOURCES) \
+	$(use_append_mchunks_SOURCES) vfd.c
 DIST_SOURCES = $(am__libdynlib1_la_SOURCES_DIST) \
 	$(am__libdynlib2_la_SOURCES_DIST) \
 	$(am__libdynlib3_la_SOURCES_DIST) $(libh5test_la_SOURCES) \
@@ -618,7 +624,8 @@ DIST_SOURCES = $(am__libdynlib1_la_SOURCES_DIST) \
 	swmr_generator.c swmr_reader.c swmr_remove_reader.c \
 	swmr_remove_writer.c swmr_sparse_reader.c swmr_sparse_writer.c \
 	swmr_writer.c tcheck_version.c $(testhdf5_SOURCES) testmeta.c \
-	$(ttsafe_SOURCES) unlink.c $(use_append_chunk_SOURCES) vfd.c
+	$(ttsafe_SOURCES) unlink.c $(use_append_chunk_SOURCES) \
+	$(use_append_mchunks_SOURCES) vfd.c
 am__can_run_installinfo = \
   case $$AM_UPDATE_INFO_DIR in \
     n|no|NO) false;; \
@@ -940,8 +947,8 @@ CHECK_CLEANFILES = *.chkexe *.chklog *.clog accum.h5 cmpd_dset.h5 \
 	earray.h5 efc[0-5].h5 log_vfd_out.log new_multi_file_v16-r.h5 \
 	new_multi_file_v16-s.h5 split_get_file_image_test-m.h5 \
 	split_get_file_image_test-r.h5 file_image_core_test.h5.copy \
-	swmr_data.h5 use_append_chunk.h5 flushrefresh.h5 \
-	flushrefresh_VERIFICATION_START \
+	swmr_data.h5 use_append_chunk.h5 use_append_mchunks.h5 \
+	flushrefresh.h5 flushrefresh_VERIFICATION_START \
 	flushrefresh_VERIFICATION_CHECKPOINT1 \
 	flushrefresh_VERIFICATION_CHECKPOINT2 \
 	flushrefresh_VERIFICATION_DONE
@@ -1009,6 +1016,7 @@ testhdf5_SOURCES = testhdf5.c tarray.c tattr.c tchecksum.c tconfig.c tfile.c \
 
 # Sources for Use Cases
 use_append_chunk_SOURCES = use_append_chunk.c use_common.c
+use_append_mchunks_SOURCES = use_append_mchunks.c use_common.c
 
 # Temporary files.
 DISTCLEANFILES = testerror.sh testlibinfo.sh testcheck_version.sh testlinks_env.sh test_plugin.sh \
@@ -1457,6 +1465,9 @@ unlink$(EXEEXT): $(unlink_OBJECTS) $(unlink_DEPENDENCIES) $(EXTRA_unlink_DEPENDE
 use_append_chunk$(EXEEXT): $(use_append_chunk_OBJECTS) $(use_append_chunk_DEPENDENCIES) $(EXTRA_use_append_chunk_DEPENDENCIES) 
 	@rm -f use_append_chunk$(EXEEXT)
 	$(AM_V_CCLD)$(LINK) $(use_append_chunk_OBJECTS) $(use_append_chunk_LDADD) $(LIBS)
+use_append_mchunks$(EXEEXT): $(use_append_mchunks_OBJECTS) $(use_append_mchunks_DEPENDENCIES) $(EXTRA_use_append_mchunks_DEPENDENCIES) 
+	@rm -f use_append_mchunks$(EXEEXT)
+	$(AM_V_CCLD)$(LINK) $(use_append_mchunks_OBJECTS) $(use_append_mchunks_LDADD) $(LIBS)
 vfd$(EXEEXT): $(vfd_OBJECTS) $(vfd_DEPENDENCIES) $(EXTRA_vfd_DEPENDENCIES) 
 	@rm -f vfd$(EXEEXT)
 	$(AM_V_CCLD)$(LINK) $(vfd_OBJECTS) $(vfd_LDADD) $(LIBS)
@@ -1587,6 +1598,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/tvltypes.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/unlink.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/use_append_chunk.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/use_append_mchunks.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/use_common.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/vfd.Po@am__quote@
 
diff --git a/test/test_usecases.sh.in b/test/test_usecases.sh.in
index bd98b60..771be71 100644
--- a/test/test_usecases.sh.in
+++ b/test/test_usecases.sh.in
@@ -31,7 +31,7 @@ EXIT_FAILURE=1
 RESULT_PASSED=" PASSED"
 RESULT_FAILED="*FAILED*"
 RESULT_SKIP="-SKIP-"
-USECASES_PROGRAMS=use_append_chunk
+USECASES_PROGRAMS="use_append_chunk use_append_mchunks"
 TESTNAME="Use Case"
 
 # Define variables
@@ -106,6 +106,10 @@ for p in $USECASES_PROGRAMS; do
     TOOLTEST $p -f $tmpfile; rm -f $tmpfile
     TOOLTEST $p -l w
     TOOLTEST $p -l r
+    # cleanup temp datafile
+    if test -z "$HDF5_NOCLEANUP"; then
+	rm -f $p.h5
+    fi
 done
 
 
diff --git a/test/use_append_mchunks.c b/test/use_append_mchunks.c
new file mode 100644
index 0000000..85abb74
--- /dev/null
+++ b/test/use_append_mchunks.c
@@ -0,0 +1,576 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
+ * access to either file, you may request a copy from help@hdfgroup.org.     *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Use Case 1.8 Appending a hyperslab of multiple chunks.
+ * Description:
+ *     Appending a hyperslab that spans several chunks of a dataset with
+ *     unlimited dimensions within a pre-created file and reading the new
+ *     data back.
+ * Goal:
+ *     Read data appended by the Writer to a pre-existing dataset in a
+ *     file. The dataset has one or more unlimited dimensions. The data
+ *     is appended by a hyperslab that is contained in several chunks (for
+ *     example, appending 2-dim planes along the slowest changing dimension
+ *     in the 3-dim dataset and each plane is covered by 4 chunks).
+ * Level:
+ *     User Level
+ * Guarantees:
+ *   o Readers will see the modified dimension sizes after the Writer
+ *     finishes HDF5 metadata updates and issues H5Fflush or H5Oflush calls.
+ *   o Readers will see newly appended data after the Writer finishes
+ *     the flush operation.
+ * 
+ * Preconditions:
+ *   o Readers are not allowed to modify the file.
+ *   o All datasets that are modified by the Writer exist when the
+ *     Writer opens the file.
+ *   o All datasets that are modified by the Writer exist when a Reader
+ *     opens the file.
+ * 
+ * Main Success Scenario:
+ *  1. An application creates a file with required objects (groups,
+ *     datasets, and attributes).
+ *  2. The Writer opens the file and datasets in the file and starts
+ *     adding data using H5Dwrite call with a hyperslab selection that
+ *     spans several chunks.
+ *  3. A Reader opens the file and a dataset in a file; if the size of
+ *     the unlimited dimension has changed, reads the appended data back.
+ * 
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/* Created: Albert Cheng, 2013/6/1.
+ * Modified:
+ */
+
+#include "use.h"
+
+/* Global Variable definitions */
+options_t UC_opts;	/* Use Case Options */
+const char *progname_g="use_append_mchunks";	/* program name */
+
+/* Create the skeleton use case file for testing.
+ * It has one 3d dataset using chunked storage.
+ * The dataset is (unlimited, 2*chunksize, 2*chunksize).
+ * Dataset type is 2 bytes integer.
+ * It starts out "empty", i.e., first dimension is 0.
+ *
+ * Return: 0 succeed; -1 fail.
+ */
+int create_uc_file(void)
+{
+    hsize_t dims[3];		/* Dataset starting dimensions */
+    hsize_t max_dims[3];	/* Dataset maximum dimensions */
+    hsize_t chunk_dims[3];	/* Chunk dimensions */
+    hid_t fid;          /* File ID for new HDF5 file */
+    hid_t dcpl;         /* Dataset creation property list */
+    hid_t sid;          /* Dataspace ID */
+    hid_t dsid;         /* Dataset ID */
+
+    /* Create the file */
+    if((fid = H5Fcreate(UC_opts.filename, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT)) < 0)
+        return -1;
+
+    /* Set up dimension sizes */
+    chunk_dims[0] = 1;
+    dims[0] = 0;
+    max_dims[0] = H5S_UNLIMITED;
+    chunk_dims[1] = chunk_dims[2] = UC_opts.chunksize;
+    max_dims[1] = max_dims[2] = dims[1] = dims[2] = 2*UC_opts.chunksize;
+
+    /* Create dataspace for creating datasets */
+    if((sid = H5Screate_simple(3, dims, max_dims)) < 0)
+        return -1;
+
+    /* Create dataset creation property list */
+    if((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
+        return -1;
+    if(H5Pset_chunk(dcpl, 3, chunk_dims) < 0)
+        return -1;
+
+    /* create dataset of progname */
+    if((dsid = H5Dcreate2(fid, progname_g, UC_DATATYPE, sid, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0)
+	return -1;
+
+    /* Close everythign */
+    if(H5Dclose(dsid) < 0)
+	return -1;
+
+    if(H5Sclose(sid) < 0)
+        return -1;
+    if(H5Fclose(fid) < 0)
+        return -1;
+
+    return 0;
+}
+
+
+/* Append planes, each of (1,2*chunksize,2*chunksize) to the dataset.
+ * In other words, 4 chunks are appended to the dataset at a time.
+ * Fill each plan with the plane number and then write it at the nth plane.
+ * Increase the plane number and repeat till the end of dataset, when it
+ * reaches chunksize long. End product is a (2*chunksize)^3 cube.
+ *
+ * Return: 0 succeed; -1 fail.
+ */
+int write_uc_file(void)
+{
+    hid_t	fid;          /* File ID for new HDF5 file */
+    hid_t	dsid;         /* dataset ID */
+    hid_t	dcpl;         /* Dataset creation property list */
+    char	*name;
+    UC_CTYPE	*buffer, *bufptr;	/* data buffer */
+    int		cz=UC_opts.chunksize;		/* Chunk size */
+    hid_t	f_sid;	    /* dataset file space id */
+    hid_t	m_sid;	    /* memory space id */
+    int		rank;	    /* rank */
+    hsize_t 	chunk_dims[3];	/* Chunk dimensions */
+    hsize_t	dims[3];    /* Dataspace dimensions */
+    hsize_t	memdims[3]; /* Memory space dimensions */
+    hsize_t	start[3] = {0,0,0}, count[3];    /* Hyperslab selection values */
+    int		i, j, k;
+
+    name = UC_opts.filename;
+
+    /* Open the file */
+    if((fid = H5Fopen(name, H5F_ACC_RDWR | (UC_opts.use_swmr ? H5F_ACC_SWMR_WRITE : 0), H5P_DEFAULT)) < 0){
+	fprintf(stderr, "H5Fopen failed\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;
+    }
+
+    /* Find chunksize used */
+    if ((dcpl = H5Dget_create_plist(dsid)) < 0){
+	fprintf(stderr, "H5Dget_create_plist failed\n");
+	return -1;
+    }
+    if (H5D_CHUNKED != H5Pget_layout(dcpl)){
+	fprintf(stderr, "storage layout is not chunked\n");
+	return -1;
+    }
+    if ((rank = H5Pget_chunk(dcpl, 3, chunk_dims)) != 3){
+	fprintf(stderr, "storage rank is not 3\n");
+	return -1;
+    }
+
+    /* verify chunk_dims is (1, chunkszie, chunksize) */
+    if (chunk_dims[0]!=1 || chunk_dims[1] != cz || chunk_dims[2] != cz){
+	fprintf(stderr, "chunk size is not as expected. Got dims=(%ld,%ld,%ld)\n",
+	    (long)chunk_dims[0], (long)chunk_dims[1], (long)chunk_dims[2]);
+	return -1;
+    }
+
+    /* allocate space for data buffer 1 X 2*chunksize X 2*chunksize of UC_CTYPE */
+    memdims[0]=1;
+    memdims[1] = memdims[2] = 2*cz;
+    if ((buffer=(UC_CTYPE*)HDmalloc(4*cz*cz*sizeof(UC_CTYPE)))==NULL) {
+	fprintf(stderr, "malloc: failed\n");
+	return -1;
+    };
+
+    /*
+     * Get dataset rank and dimension.
+     */
+    f_sid = H5Dget_space(dsid);    /* Get filespace handle first. */
+    rank  = H5Sget_simple_extent_ndims(f_sid);
+    if (rank != 3){
+	fprintf(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;
+    }
+    printf("dataset rank %d, dimensions %lu x %lu x %lu\n",
+	   rank, (unsigned long)(dims[0]), (unsigned long)(dims[1]), (unsigned long)(dims[2]));
+    /* verify that file space dims are as expected and are consistent with memory space dims */
+    if (dims[0] != 0 || dims[1] != memdims[1] || dims[2] != memdims[2]){
+	fprintf(stderr, "dataset is not empty. Got dims=(%ld,%ld,%ld)\n",
+	    (long)dims[0], (long)dims[1], (long)dims[2]);
+	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;
+    };
+
+    /* write planes */
+    count[0]=1;
+    count[1]=count[2]=2*cz;
+    for (i=0; i<UC_opts.nplanes; i++){
+	/* fill buffer with value i+1 */
+	bufptr = buffer;
+	for (j=0; j<2*cz; j++)
+	    for (k=0; k<2*cz; k++)
+		*bufptr++ = i;
+
+	/* extend the dataset by one for new plane */
+	dims[0]=i+1;
+        if(H5Dset_extent(dsid, dims) < 0){
+	    fprintf(stderr, "H5Dset_extent failed\n");
+            return -1;
+	}
+
+        /* Get the dataset's dataspace */
+        if((f_sid = H5Dget_space(dsid)) < 0){
+	    fprintf(stderr, "H5Dset_extent failed\n");
+            return -1;
+	}
+
+	start[0]=i;
+        /* Choose the next plane to write */
+        if(H5Sselect_hyperslab(f_sid, H5S_SELECT_SET, start, NULL, count, NULL) < 0){
+	    fprintf(stderr, "Failed H5Sselect_hyperslab\n");
+            return -1;
+	}
+
+        /* Write plane to the dataset */
+        if(H5Dwrite(dsid, UC_DATATYPE, m_sid, f_sid, H5P_DEFAULT, buffer) < 0){
+	    fprintf(stderr, "Failed H5Dwrite\n");
+            return -1;
+	}
+	/* flush file to make the just written plane available. */
+	if(H5Fflush(fid, H5F_SCOPE_GLOBAL) < 0){
+	    fprintf(stderr, "Failed to H5Fflush file\n");
+	    return -1;
+	}
+    }
+
+    /* Done writing. Free/Close all resources including data file */
+    HDfree(buffer);
+    if (H5Dclose(dsid) < 0){
+	fprintf(stderr, "Failed to close datasete\n");
+	return -1;
+    }
+    if (H5Sclose(m_sid) < 0){
+	fprintf(stderr, "Failed to close memory space\n");
+	return -1;
+    }
+    if (H5Sclose(f_sid) < 0){
+	fprintf(stderr, "Failed to close file space\n");
+	return -1;
+    }
+    if (H5Fclose(fid) < 0){
+	fprintf(stderr, "Failed to close file id\n");
+	return -1;
+    }
+
+    return 0;
+}
+
+
+/* Read planes from the dataset.
+ * It expects the dataset is being changed (growing).
+ * It checks the unlimited dimension (1st one). When it increases,
+ * it will read in the new planes, one by one, and verify the data correctness.
+ * (The nth plan should contain all "n".)
+ * When the unlimited dimension grows to the chunksize (it becomes a cube),
+ * that is the expected end of data, the reader exits.
+ *
+ * Return: 0 succeed; -1 fail.
+ */
+int read_uc_file(void)
+{
+    hid_t	fid;          /* File ID for new HDF5 file */
+    hid_t	dsid;         /* dataset ID */
+    char	*name;
+    UC_CTYPE	*buffer, *bufptr;	/* read data buffer */
+    int		cz=UC_opts.chunksize;		/* Chunk size */
+    hid_t	f_sid;	    /* dataset file space id */
+    hid_t	m_sid;	    /* memory space id */
+    int		rank;	    /* rank */
+    hsize_t	dims[3];    /* Dataspace dimensions */
+    hsize_t	memdims[3]; /* Memory space dimensions */
+    int		nplane=0, nplane_old=0;	/* nth plane, last nth plane */
+    hsize_t	start[3] = {0,0,0}, count[3];    /* Hyperslab selection values */
+    int		j, k;
+    int		nreadererr=0;
+    int		nerrs;
+    int		nonewplane;
+
+    name = UC_opts.filename;
+
+    /* Open the file */
+    if((fid = H5Fopen(name, H5F_ACC_RDONLY | (UC_opts.use_swmr ? H5F_ACC_SWMR_READ : 0), H5P_DEFAULT)) < 0){
+	fprintf(stderr, "H5Fopen failed\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;
+    }
+
+    /* allocate space for data buffer 1 X 2*chunksize X 2*chunksize of UC_CTYPE */
+    memdims[0]=1;
+    memdims[1] = memdims[2] = 2*cz;
+    if ((buffer=(UC_CTYPE*)HDmalloc(4*cz*cz*sizeof(UC_CTYPE)))==NULL) {
+	fprintf(stderr, "malloc: failed\n");
+	return -1;
+    };
+
+    /*
+     * Get dataset rank and dimension.
+     * Verify dimension is as expected (unlimited,2*chunksize,2*chunksize).
+     */
+    f_sid = H5Dget_space(dsid);    /* Get filespace handle first. */
+    rank  = H5Sget_simple_extent_ndims(f_sid);
+    if (rank != 3){
+	fprintf(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;
+    }
+    printf("dataset rank %d, dimensions %lu x %lu x %lu\n",
+	   rank, (unsigned long)(dims[0]), (unsigned long)(dims[1]), (unsigned 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=(%ld,%ld,%ld)\n",
+	    (long)dims[0], (long)dims[1], (long)dims[2]);
+	fprintf(stderr, "But memdims=(%ld,%ld,%ld)\n",
+	    (long)memdims[0], (long)memdims[1], (long)memdims[2]);
+	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;
+    };
+
+    /* Read 1 plane at a time whenever the dataset grows larger
+     * (along dim[0]) */
+    count[0]=1;
+    count[1]=count[2]=2*cz;
+    /* quit when all nplanes, default cz, have been read */
+    nonewplane=0;
+    while (nplane_old < UC_opts.nplanes ){
+	/* 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;
+	    }
+	    printf("reading planes %d to %d\n", nplane_old, (int)dims[0]);
+	}else{
+	    if (nonewplane){
+		printf(".");
+		if (nonewplane>=30){
+		    fprintf(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 ");
+	    }
+	    nonewplane++;
+	    /* pause for a second */
+	    sleep(1);
+	}
+	for (nplane=nplane_old; nplane < dims[0]; nplane++){
+	    /* 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;
+	    }
+
+	    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;
+	    }
+
+	    /* 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;
+	    }
+
+	    /* compare read data with expected data value which is nplane */
+	    bufptr = buffer;
+	    nerrs=0;
+	    for (j=0; j<2*cz; j++){
+		for (k=0; k<2*cz; k++){
+		    if (*bufptr++ != nplane){
+			if (++nerrs < ErrorReportMax){
+			    fprintf(stderr,
+				"found error %d plane(%d,%d), expected %d, got %d\n",
+				nplane, j, k, nplane, (int)*(bufptr-1));
+			}
+		    }
+		}
+	    }
+	    if (nerrs){
+		nreadererr++;
+		fprintf(stderr, "found %d unexpected values in plane %d\n", nerrs, nplane);
+	    }
+	}
+	/* Have read all current planes */
+	nplane_old=dims[0];
+
+	/* check if dataset has grown since last time */
+	/* close dsid and file, then reopen them */
+	if (H5Dclose(dsid) < 0){
+	    fprintf(stderr, "H5Dclose failed\n");
+	    return -1;
+	}
+	if (H5Fclose(fid) < 0){
+	    fprintf(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");
+	    return -1;
+	}
+	if((dsid = H5Dopen2(fid, progname_g, H5P_DEFAULT)) < 0){
+	    fprintf(stderr, "H5Dopen2 failed\n");
+	    return -1;
+	}
+	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");
+	    return -1;
+	}
+    }
+
+    if (nreadererr)
+	return -1;
+    else
+	return 0;
+}
+
+
+/* Overall Algorithm: 
+ * Parse options from user;
+ * Generate/pre-created test files needed and close it;
+ * fork: child process becomes the reader process;
+ *       while parent process continues as the writer process;
+ * both run till ending conditions are met.
+ */
+int
+main(int argc, char *argv[])
+{
+    pid_t childpid=0;
+    pid_t mypid, tmppid;
+    int	child_status;
+    int child_wait_option=0;
+    int ret_value = 0;
+    int child_ret_value;
+
+    /* initialization */
+    /* use case defaults */
+    HDmemset(&UC_opts, 0, sizeof(options_t));
+    UC_opts.h5_use_chunks = 1;	/* use chunked datasets */
+    UC_opts.chunksize = Chunksize_DFT;
+    UC_opts.use_swmr = 1;	/* use swmr open */
+
+    /* parse options */
+    if (parse_option(argc, argv) < 0){
+	Hgoto_error(1);
+    }
+
+    /* ==============================================================*/
+    /* UC_READWRITE: create datafile, launch both reader and writer. */
+    /* UC_WRITER:    create datafile, skip reader, launch writer.    */
+    /* UC_READER:    skip create, launch reader, exit.               */
+    /* ==============================================================*/
+    /* ============*/
+    /* 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");
+    }
+
+    if (UC_opts.launch==UC_READWRITE){
+	/* fork process */
+	if((childpid = fork()) < 0) {
+	    perror("fork");
+	    Hgoto_error(1);
+	};
+    };
+    mypid = getpid();
+
+    /* ============= */
+    /* 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() < 0){
+		fprintf(stderr, "read_uc_file encountered error\n");
+		exit(1);
+	    }
+	    exit(0);
+	}
+    }
+
+    /* ============= */
+    /* launch writer */
+    /* ============= */
+    /* this process continues to launch the writer */
+    printf("%d: continue as the writer process\n", mypid);
+    if (write_uc_file() < 0){
+	fprintf(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);
+	}
+    }
+    
+done:
+    /* Print result and exit */
+    if (ret_value != 0){
+	printf("Error(s) encountered\n");
+    }else{
+	printf("All passed\n");
+    }
+
+    return(ret_value);
+}