[svn-r15433] http://bugzilla.hdfgroup.uiuc.edu/show_bug.cgi?id=1170

Summary: when using h5diff to compare the results of h5repack (or other tools that copy one HDF5 file to another), a new option is needed to allow h5diff to make an "absolute" comparison of the 2 files. This is the "contents" mode explained in the usage below.


If this mode is present, objects in both files must match (must be exactly the same). If this does not happen, the tool returns an error code of 1 (instead of the success code of 0)


Changes to the h5repack test script: the call to h5diff was changed to include -c (maintaining the previous -q). 


tested: windows, linux

26 files changed, 570 insertions, 294 deletions

diff --git a/tools/h5diff/h5diff_common.c b/tools/h5diff/h5diff_common.c
index 357bb32..05111a9 100644
--- a/tools/h5diff/h5diff_common.c
+++ b/tools/h5diff/h5diff_common.c
@@ -31,7 +31,7 @@ const char  *progname = "h5diff";
  * Command-line options: The user can specify short or long-named
  * parameters.
  */
-static const char *s_opts = "hVrvqn:d:p:";
+static const char *s_opts = "hVrvqn:d:p:c";
 static struct long_options l_opts[] = {
     { "help", no_arg, 'h' },
     { "version", no_arg, 'V' },
@@ -41,6 +41,7 @@ static struct long_options l_opts[] = {
     { "count", require_arg, 'n' },
     { "delta", require_arg, 'd' },
     { "relative", require_arg, 'p' },
+    { "contents", no_arg, 'c' },
     { NULL, 0, '\0' }
 };
 
@@ -91,6 +92,9 @@ void parse_command_line(int argc,
         case 'r':
             options->m_report = 1;
             break;
+        case 'c':
+            options->m_contents = 1;
+            break;
         case 'd':
             options->d=1;
             
@@ -170,7 +174,7 @@ void parse_command_line(int argc,
 
  void  print_info(diff_opt_t* options)
  {
-     if (options->m_quiet || options->err_stat)
+     if (options->m_quiet || options->err_stat || options->m_contents)
          return;
      
      if (options->cmn_objs==0)
@@ -318,8 +322,10 @@ void usage(void)
  printf("   -V, --version           Print version number and exit\n");
  printf("   -r, --report            Report mode. Print differences\n");
  printf("   -v, --verbose           Verbose mode. Print differences, list of objects\n");
-  
  printf("   -q, --quiet             Quiet mode. Do not do output\n");
+ printf("   -c, --contents          Contents mode. Objects in both files must match\n");
+
+
  printf("   -n C, --count=C         Print differences up to C number\n");
  printf("   -d D, --delta=D         Print difference when greater than limit D\n");
  printf("   -p R, --relative=R      Print difference when greater than relative limit R\n");
@@ -339,6 +345,22 @@ void usage(void)
  printf("  -r Report mode: print the above plus the differences\n");
  printf("  -v Verbose mode: print the above plus a list of objects and warnings\n");
  printf("  -q Quiet mode: do not print output\n");
+ printf("  -c Contents mode: objects in both files must match\n");
+
+ printf("\n");
+
+ printf(" Compare criteria\n");
+ printf("\n");
+ printf(" If no objects [obj1[obj2]] are specified, h5diff only compares objects\n");
+ printf("   with the same absolute path in both files. However,\n");
+ printf("   when the -c flag is present, (contents mode) the objects in file1\n");
+ printf("   must match exactly the objects in file2\n");
+ printf("\n");
+   
+ printf(" The compare criteria is:\n");
+ printf("   1) datasets: numerical array differences 2) groups: name string difference\n");
+ printf("   3) datatypes: the return value of H5Tequal 2) links: name string difference\n");
+ printf("   of the linked value\n");
 
  printf("\n");
 
@@ -368,11 +390,7 @@ void usage(void)
  printf("\n");
  printf("    to compare '/g1/dset1' and '/g1/dset2' in the same file\n");
  printf("\n");
- printf(" If no objects [obj1[obj2]] are specified, h5diff only compares objects\n");
- printf("   with the same absolute path in both files. The compare criteria is:\n");
- printf("   1) datasets: numerical array differences 2) groups: name string difference\n");
- printf("   3) datatypes: the return value of H5Tequal 2) links: name string difference\n");
- printf("   of the linked value\n");
+
 
 }
 
diff --git a/tools/h5diff/h5diff_main.c b/tools/h5diff/h5diff_main.c
index 54a075f..17fe275 100644
--- a/tools/h5diff/h5diff_main.c
+++ b/tools/h5diff/h5diff_main.c
@@ -89,6 +89,10 @@ int main(int argc, const char *argv[])
     */
 
     ret = (nfound == 0 ? 0 : 1 );
+
+    if ( options.m_contents && options.contents == 0 )
+        ret = 1;
+
     if(options.err_stat)
         ret = -1;
     return ret;
diff --git a/tools/h5diff/h5diffgentest.c b/tools/h5diff/h5diffgentest.c
index 74b3aa2..e1a554e 100644
--- a/tools/h5diff/h5diffgentest.c
+++ b/tools/h5diff/h5diffgentest.c
@@ -146,7 +146,7 @@ int test_basic(const char *fname1, const char *fname2, const char *fname3)
 	fprintf(stderr, "empty file (%s) close failed.\n", fname3);
         goto out;
     }
-
+    
    /*-------------------------------------------------------------------------
     * create two files
     *-------------------------------------------------------------------------
@@ -265,7 +265,6 @@ int test_basic(const char *fname1, const char *fname2, const char *fname3)
     */
     {
 
-#if 1
         float data15[6];
         float data16[6];
 
@@ -285,48 +284,9 @@ int test_basic(const char *fname1, const char *fname2, const char *fname3)
 
         write_dset(gid1,1,dims1,"fp15",H5T_NATIVE_FLOAT,data15);
         write_dset(gid1,1,dims1,"fp16",H5T_NATIVE_FLOAT,data16);
-#else
-
-#define NU_ELMTS 1000000
-
-        hsize_t i;
-
-        hsize_t dims2[1] = { NU_ELMTS };
-
-        float *data15 = malloc (NU_ELMTS * sizeof(float) );
-        float *data16 = malloc (NU_ELMTS * sizeof(float) );
-
-        data15[0] = (float) sqrt( (double)-1 );
-        data15[1] = 1;
-        data15[2] = (float) sqrt( (double)-1 );
-        data15[3] = 1;
-        data15[4] = 1;
-        data15[5] = 1;
-
-        data16[0] = (float) sqrt( (double)-1 );
-        data16[1] = (float) sqrt( (double)-1 );
-        data16[2] = 1;
-        data16[3] = 1;
-        data16[4] = 1;
-        data16[5] = 1;
-
-        for ( i = 6; i < NU_ELMTS; i++ )
-        {
-            data15[i] = /*data15[0];*/ 2;
-            data16[i] = 1;
-        }
-
-        write_dset(gid1,1,dims2,"fp15",H5T_NATIVE_FLOAT,data15);
-        write_dset(gid1,1,dims2,"fp16",H5T_NATIVE_FLOAT,data16);
-
-        free( data15 );
-        free( data16 );
-#endif
 
     }
-
        
-        
    /*-------------------------------------------------------------------------
     * NaNs in H5T_NATIVE_DOUBLE
     *-------------------------------------------------------------------------
@@ -354,9 +314,7 @@ int test_basic(const char *fname1, const char *fname2, const char *fname3)
         write_dset(gid1,1,dims1,"fp18",H5T_NATIVE_DOUBLE,data18);
 
     }
-        
-
-  
+ 
     
    /*-------------------------------------------------------------------------
     * close
@@ -783,13 +741,13 @@ int test_datasets(const char *file,
 
     write_dset_in(gid,"/dset",fid,make_diffs);
 
-    /* Close */
+    /* close */
     status = H5Dclose(did);
     assert(status >= 0);
     status = H5Gclose(gid);
     assert(status >= 0);
 
-    /* Close file */
+    /* close file */
     status = H5Fclose(fid);
     assert(status >= 0);
     return status;
@@ -2666,31 +2624,35 @@ int write_attr(hid_t loc_id,
                hid_t tid,
                void *buf)
 {
- hid_t   aid;
- hid_t   sid;
-
- /* create a space  */
- if((sid = H5Screate_simple(rank, dims, NULL)) < 0)
-     goto out;
-
- /* create the attribute */
- if((aid = H5Acreate2(loc_id, name, tid, sid, H5P_DEFAULT, H5P_DEFAULT)) < 0)
-     goto out;
-
- /* write */
- if(buf)
-   if(H5Awrite(aid, tid, buf) < 0)
-      goto out;
-
- /* close */
- H5Aclose(aid);
- H5Sclose(sid);
-
- return SUCCEED;
-
+    hid_t   aid=-1;
+    hid_t   sid=-1;
+    
+    /* create a space  */
+    if((sid = H5Screate_simple(rank, dims, NULL)) < 0)
+        goto out;
+    
+    /* create the attribute */
+    if((aid = H5Acreate2(loc_id, name, tid, sid, H5P_DEFAULT, H5P_DEFAULT)) < 0)
+        goto out;
+    
+    /* write */
+    if(buf)
+    {
+        if(H5Awrite(aid, tid, buf) < 0)
+            goto out;
+    }
+        
+    /* close */
+    H5Aclose(aid);
+    H5Sclose(sid);
+        
+    return SUCCEED;
+        
 out:
- 
- return FAIL;
+    
+    H5Aclose(aid);
+    H5Sclose(sid);
+    return FAIL;
 }
 
 /*-------------------------------------------------------------------------
@@ -2708,8 +2670,8 @@ int write_dset( hid_t loc_id,
                 hid_t tid,
                 void *buf )
 {
-    hid_t   did;
-    hid_t   sid;
+    hid_t   did=-1;
+    hid_t   sid=-1;
 
     /* create a space  */
     if((sid = H5Screate_simple(rank, dims, NULL)) < 0)
@@ -2721,8 +2683,10 @@ int write_dset( hid_t loc_id,
 
     /* write */
     if(buf)
+    {
         if(H5Dwrite(did, tid, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf) < 0)
             goto out;
+    }
 
     /* close */
     H5Dclose(did);
@@ -2731,6 +2695,9 @@ int write_dset( hid_t loc_id,
     return SUCCEED;
 
 out:
+
+    H5Dclose(did);
+    H5Sclose(sid);
     return FAIL;
 }
 
diff --git a/tools/h5diff/testh5diff.sh b/tools/h5diff/testh5diff.sh
index 6685a66..208bb29 100755
--- a/tools/h5diff/testh5diff.sh
+++ b/tools/h5diff/testh5diff.sh
@@ -39,6 +39,7 @@ FILE7=h5diff_dset1.h5
 FILE8=h5diff_dset2.h5
 FILE9=h5diff_hyper1.h5
 FILE10=h5diff_hyper2.h5
+FILE11=h5diff_empty.h5
 
 
 H5DIFF=h5diff               # The tool name
@@ -301,6 +302,9 @@ TOOLTEST h5diff_17.txt -v $FILE1 $FILE2
 # 1.8 quiet mode 
 TOOLTEST h5diff_18.txt -q $FILE1 $FILE2 
 
+# 1.9 contents mode 
+TOOLTEST h5diff_19.txt -v -c $FILE1 $FILE11 
+
 # ##############################################################################
 # # not comparable types
 # ##############################################################################
diff --git a/tools/h5repack/h5repack.sh.in b/tools/h5repack/h5repack.sh.in
index 77be575..e6d9a98 100755
--- a/tools/h5repack/h5repack.sh.in
+++ b/tools/h5repack/h5repack.sh.in
@@ -93,9 +93,9 @@ DIFFTEST()
 {
     VERIFY  $@
     if [ "`uname -s`" = "TFLOPS O/S" ]; then
-     $RUNSERIAL $H5DIFF_BIN -q $@ 
+     $RUNSERIAL $H5DIFF_BIN -q -c $@ 
     else
-     $RUNSERIAL $H5DIFF_BIN -q "$@" 
+     $RUNSERIAL $H5DIFF_BIN -q -c "$@" 
     fi
     RET=$?
     if [ $RET != 0 ] ; then
diff --git a/tools/h5repack/h5repacktst.c b/tools/h5repack/h5repacktst.c
index 99448c4..3796179 100644
--- a/tools/h5repack/h5repacktst.c
+++ b/tools/h5repack/h5repacktst.c
@@ -152,6 +152,9 @@ int main (void)
  memset(&diff_options, 0, sizeof (diff_opt_t));
  memset(&pack_options, 0, sizeof (pack_opt_t));
 
+ /* set h5diff "contents" mode */
+ diff_options.m_contents = 1;
+
  /* run tests  */
  puts("Testing h5repack:");
 
diff --git a/tools/lib/h5diff.c b/tools/lib/h5diff.c
index 4f4074f..3bd6fb3 100644
--- a/tools/lib/h5diff.c
+++ b/tools/lib/h5diff.c
@@ -186,15 +186,17 @@ hsize_t h5diff(const char *fname1,
                const char *objname2,
                diff_opt_t *options)
 {
-    trav_info_t  *info1;
-    trav_info_t  *info2;
-    hid_t        file1_id = (-1), file2_id = (-1);
+    trav_info_t  *info1=NULL;
+    trav_info_t  *info2=NULL;
+    hid_t        file1_id = (-1);
+    hid_t        file2_id = (-1);
     char         filenames[2][1024];
     hsize_t      nfound = 0;
 
     HDmemset(filenames, 0, 1024 * 2);
 
-    if(options->m_quiet && (options->m_verbose || options->m_report)) {
+    if(options->m_quiet && (options->m_verbose || options->m_report)) 
+    {
         printf("Error: -q (quiet mode) cannot be added to verbose or report modes\n");
         options->err_stat=1;
         return 0;
@@ -206,9 +208,11 @@ hsize_t h5diff(const char *fname1,
     */
 
     /* disable error reporting */
-    H5E_BEGIN_TRY {
-        /* Open the files */
-        if((file1_id = H5Fopen(fname1, H5F_ACC_RDONLY, H5P_DEFAULT)) < 0) {
+    H5E_BEGIN_TRY 
+    {
+        /* open the files */
+        if((file1_id = H5Fopen(fname1, H5F_ACC_RDONLY, H5P_DEFAULT)) < 0) 
+        {
             printf("h5diff: <%s>: unable to open file\n", fname1);
             options->err_stat = 1;
 
@@ -219,7 +223,8 @@ hsize_t h5diff(const char *fname1,
 #endif
             goto out;
         } /* end if */
-        if((file2_id = H5Fopen(fname2, H5F_ACC_RDONLY, H5P_DEFAULT)) < 0) {
+        if((file2_id = H5Fopen(fname2, H5F_ACC_RDONLY, H5P_DEFAULT)) < 0) 
+        {
             printf("h5diff: <%s>: unable to open file\n", fname2);
             options->err_stat = 1;
 
@@ -255,11 +260,12 @@ hsize_t h5diff(const char *fname1,
         goto out;
     } /* end if */
 
-    /*-------------------------------------------------------------------------
+   /*-------------------------------------------------------------------------
     * object name was supplied
     *-------------------------------------------------------------------------
     */
-    if(objname1) {
+    if( objname1 ) 
+    {
 #ifdef H5_HAVE_PARALLEL
         if(g_Parallel)
             /* Let tasks know that they won't be needed */
@@ -267,22 +273,31 @@ hsize_t h5diff(const char *fname1,
 #endif
         assert(objname2);
         options->cmn_objs = 1; /* eliminate warning */
-        nfound = diff_compare(file1_id, fname1, objname1, info1,
-                              file2_id, fname2, objname2, info2,
+        nfound = diff_compare(file1_id, 
+                              fname1, 
+                              objname1, 
+                              info1,
+                              file2_id, 
+                              fname2, 
+                              objname2, 
+                              info2,
                               options);
     } /* end if */
 
-    /*-------------------------------------------------------------------------
+   /*-------------------------------------------------------------------------
     * compare all
     *-------------------------------------------------------------------------
     */
 
-    else {
+    else 
+    {
 #ifdef H5_HAVE_PARALLEL
-        if(g_Parallel) {
+        if(g_Parallel) 
+        {
             int i;
 
-            if((HDstrlen(fname1) > 1024) || (HDstrlen(fname2) > 1024)) {
+            if((HDstrlen(fname1) > 1024) || (HDstrlen(fname2) > 1024)) 
+            {
                 fprintf(stderr, "The parallel diff only supports path names up to 1024 characters\n");
                 MPI_Abort(MPI_COMM_WORLD, 0);
             } /* end if */
@@ -295,7 +310,12 @@ hsize_t h5diff(const char *fname1,
                 MPI_Send(filenames, (1024 * 2), MPI_CHAR, i, MPI_TAG_PARALLEL, MPI_COMM_WORLD);
         } /* end if */
 #endif
-        nfound = diff_match(file1_id, info1, file2_id, info2, options);
+
+        nfound = diff_match(file1_id, 
+                            info1, 
+                            file2_id, 
+                            info2, 
+                            options);
     } /* end else */
 
     trav_info_free(info1);
@@ -303,7 +323,8 @@ hsize_t h5diff(const char *fname1,
 
 out:
     /* close */
-    H5E_BEGIN_TRY {
+    H5E_BEGIN_TRY 
+    {
         H5Fclose(file1_id);
         H5Fclose(file2_id);
     } H5E_END_TRY;
@@ -332,26 +353,28 @@ out:
  *-------------------------------------------------------------------------
  */
 hsize_t diff_match(hid_t file1_id,
-                    trav_info_t * info1,
-                    hid_t file2_id,
-                    trav_info_t * info2,
-                    diff_opt_t * options)
+                   trav_info_t *info1,
+                   hid_t file2_id,
+                   trav_info_t *info2,
+                   diff_opt_t *options)
 {
     trav_table_t *table = NULL;
-    size_t curr1, curr2;
-    unsigned infile[2];
-    hsize_t nfound = 0;
-    unsigned i;
+    size_t       curr1;
+    size_t       curr2;
+    unsigned     infile[2];
+    hsize_t      nfound = 0;
+    unsigned     i;
 
     /*-------------------------------------------------------------------------
     * build the list
     *-------------------------------------------------------------------------
     */
-    trav_table_init(&table);
+    trav_table_init( &table );
 
     curr1 = 0;
     curr2 = 0;
-    while(curr1 < info1->nused && curr2 < info2->nused) {
+    while(curr1 < info1->nused && curr2 < info2->nused) 
+    {
         /* criteria is string compare */
         int cmp = HDstrcmp(info1->paths[curr1].path, info2->paths[curr2].path);
 
@@ -363,13 +386,15 @@ hsize_t diff_match(hid_t file1_id,
             curr1++;
             curr2++;
         } /* end if */
-        else if(cmp < 0) {
+        else if(cmp < 0) 
+        {
             infile[0] = 1;
             infile[1] = 0;
             trav_table_addflags(infile, info1->paths[curr1].path, info1->paths[curr1].type, table);
             curr1++;
         } /* end else-if */
-        else {
+        else 
+        {
             infile[0] = 0;
             infile[1] = 1;
             trav_table_addflags(infile, info2->paths[curr2].path, info2->paths[curr2].type, table);
@@ -380,7 +405,8 @@ hsize_t diff_match(hid_t file1_id,
     /* list1 did not end */
     infile[0] = 1;
     infile[1] = 0;
-    while(curr1 < info1->nused) {
+    while(curr1 < info1->nused) 
+    {
         trav_table_addflags(infile, info1->paths[curr1].path, info1->paths[curr1].type, table);
         curr1++;
     } /* end while */
@@ -388,16 +414,18 @@ hsize_t diff_match(hid_t file1_id,
     /* list2 did not end */
     infile[0] = 0;
     infile[1] = 1;
-    while(curr2 < info2->nused) {
+    while(curr2 < info2->nused) 
+    {
         trav_table_addflags(infile, info2->paths[curr2].path, info2->paths[curr2].type, table);
         curr2++;
     } /* end while */
 
-    /*-------------------------------------------------------------------------
+   /*-------------------------------------------------------------------------
     * print the list
     *-------------------------------------------------------------------------
     */
-    if(options->m_verbose) {
+    if(options->m_verbose) 
+    {
         printf("\n");
         printf("file1     file2\n");
         printf("---------------------------------------\n");
@@ -412,6 +440,35 @@ hsize_t diff_match(hid_t file1_id,
     } /* end if */
 
 
+
+    /*-------------------------------------------------------------------------
+    * contents mode. we do an "absolute" compare criteria, the number of objects
+    * in file1 must be the same as in file2
+    *-------------------------------------------------------------------------
+    */
+    if ( options->m_contents )
+    {
+        /* assume equal contents initially */
+        options->contents = 1;
+        
+        /* number of different objects */
+        if ( info1->nused != info2->nused )
+        {
+            options->contents = 0;
+        }
+        
+        
+        for( i = 0; i < table->nobjs; i++) 
+        {
+            if( table->objs[i].flags[0] != table->objs[i].flags[1] ) 
+            {
+                options->contents = 0;
+            }
+        }
+        
+    }
+
+
     /*-------------------------------------------------------------------------
     * do the diff for common objects
     *-------------------------------------------------------------------------
@@ -430,17 +487,21 @@ hsize_t diff_match(hid_t file1_id,
     HDmemset(workerTasks, 1, (g_nTasks - 1));
 #endif
 
-    for(i = 0; i < table->nobjs; i++) {
-        if(table->objs[i].flags[0] && table->objs[i].flags[1]) {
+    for(i = 0; i < table->nobjs; i++) 
+    {
+        if( table->objs[i].flags[0] && table->objs[i].flags[1]) 
+        {
             options->cmn_objs = 1;
-            if(!g_Parallel) {
+            if(!g_Parallel) 
+            {
                 nfound += diff(file1_id,
                         table->objs[i].name,
                         file2_id,
                         table->objs[i].name, options, table->objs[i].type);
             } /* end if */
 #ifdef H5_HAVE_PARALLEL
-            else {
+            else 
+            {
                 int workerFound = 0;
 
                 h5diffdebug("beginning of big else block\n");
@@ -453,7 +514,8 @@ hsize_t diff_match(hid_t file1_id,
                 */
 
                 /*Set up args to pass to worker task. */
-                if(HDstrlen(table->objs[i].name) > 255) {
+                if(HDstrlen(table->objs[i].name) > 255) 
+                {
                     printf("The parallel diff only supports object names up to 255 characters\n");
                     MPI_Abort(MPI_COMM_WORLD, 0);
                 } /* end if */
@@ -464,14 +526,16 @@ hsize_t diff_match(hid_t file1_id,
 
                 h5diffdebug2("busyTasks=%d\n", busyTasks);
                 /* if there are any outstanding print requests, let's handle one. */
-                if(busyTasks > 0) {
+                if(busyTasks > 0) 
+                {
                     int incomingMessage;
 
                     /* check if any tasks freed up, and didn't need to print. */
                     MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_DONE, MPI_COMM_WORLD, &incomingMessage, &Status);
 
                     /* first block*/
-                    if(incomingMessage) {
+                    if(incomingMessage) 
+                    {
                         workerTasks[Status.MPI_SOURCE - 1] = 1;
                         MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_DONE, MPI_COMM_WORLD, &Status);
                         nfound += nFoundbyWorker.nfound;
@@ -480,7 +544,8 @@ hsize_t diff_match(hid_t file1_id,
                     } /* end if */
 
                     /* check to see if the print token was returned. */
-                    if(!havePrintToken) {
+                    if(!havePrintToken) 
+                    {
                         /* If we don't have the token, someone is probably sending us output */
                         print_incoming_data();
 
@@ -499,10 +564,12 @@ hsize_t diff_match(hid_t file1_id,
                     } /* end if */
 
                     /* check to see if anyone needs the print token. */
-                    if(havePrintToken) {
+                    if(havePrintToken) 
+                    {
                         /* check incoming queue for print token requests */
                         MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_TOK_REQUEST, MPI_COMM_WORLD, &incomingMessage, &Status);
-                        if(incomingMessage) {
+                        if(incomingMessage) 
+                        {
                             MPI_Recv(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_TOK_REQUEST, MPI_COMM_WORLD, &Status);
                             MPI_Send(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_PRINT_TOK, MPI_COMM_WORLD);
                             havePrintToken = 0;
@@ -513,8 +580,10 @@ hsize_t diff_match(hid_t file1_id,
                 /* check array of tasks to see which ones are free.
                 * Manager task never does work, so freeTasks[0] is really
                 * worker task 0. */
-                for(n = 1; (n < g_nTasks) && !workerFound; n++) {
-                    if(workerTasks[n-1]) {
+                for(n = 1; (n < g_nTasks) && !workerFound; n++) 
+                {
+                    if(workerTasks[n-1]) 
+                    {
                         /* send file id's and names to first free worker */
                         MPI_Send(&args, sizeof(args), MPI_BYTE, n, MPI_TAG_ARGS, MPI_COMM_WORLD);
 
@@ -528,20 +597,24 @@ hsize_t diff_match(hid_t file1_id,
                 } /* end for */
 
                 h5diffdebug2("workerfound is %d \n", workerFound);
-                if(!workerFound) {
+                if(!workerFound) 
+                {
                     /* if they were all busy, we've got to wait for one free up
                      *  before we can move on.  If we don't have the token, some
                      * task is currently printing so we'll wait for that task to
                      * return it.
                      */
 
-                    if(!havePrintToken) {
-                        while(!havePrintToken) {
+                    if(!havePrintToken) 
+                    {
+                        while(!havePrintToken) 
+                        {
                             int incomingMessage;
 
                             print_incoming_data();
                             MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &incomingMessage, &Status);
-                            if(incomingMessage) {
+                            if(incomingMessage) 
+                            {
                                 MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, MPI_ANY_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &Status);
                                 havePrintToken = 1;
                                 nfound += nFoundbyWorker.nfound;
@@ -552,23 +625,27 @@ hsize_t diff_match(hid_t file1_id,
                         } /* end while */
                     } /* end if */
                     /* if we do have the token, check for task to free up, or wait for a task to request it */
-                    else {
+                    else 
+                    {
                         /* But first print all the data in our incoming queue */
                         print_incoming_data();
                         MPI_Probe(MPI_ANY_SOURCE, MPI_ANY_TAG, MPI_COMM_WORLD, &Status);
-                        if(Status.MPI_TAG == MPI_TAG_DONE) {
+                        if(Status.MPI_TAG == MPI_TAG_DONE) 
+                        {
                             MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_DONE, MPI_COMM_WORLD, &Status);
                             nfound += nFoundbyWorker.nfound;
                             options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
                             MPI_Send(&args, sizeof(args), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_ARGS, MPI_COMM_WORLD);
                         } /* end if */
-                        else if(Status.MPI_TAG == MPI_TAG_TOK_REQUEST) {
+                        else if(Status.MPI_TAG == MPI_TAG_TOK_REQUEST) 
+                        {
                             int incomingMessage;
 
                             MPI_Recv(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_TOK_REQUEST, MPI_COMM_WORLD, &Status);
                             MPI_Send(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_PRINT_TOK, MPI_COMM_WORLD);
 
-                            do {
+                            do 
+                            {
                                 MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &incomingMessage, &Status);
 
                                 print_incoming_data();
@@ -579,7 +656,8 @@ hsize_t diff_match(hid_t file1_id,
                             options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
                             MPI_Send(&args, sizeof(args), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_ARGS, MPI_COMM_WORLD);
                         } /* end else-if */
-                        else {
+                        else 
+                        {
                             printf("ERROR: Invalid tag (%d) received \n", Status.MPI_TAG);
                             MPI_Abort(MPI_COMM_WORLD, 0);
                             MPI_Finalize();
@@ -593,26 +671,32 @@ hsize_t diff_match(hid_t file1_id,
     h5diffdebug("done with for loop\n");
 
 #ifdef H5_HAVE_PARALLEL
-    if(g_Parallel) {
+    if(g_Parallel) 
+    {
         /* make sure all tasks are done */
-        while(busyTasks > 0) {
+        while(busyTasks > 0) 
+        {
             MPI_Probe(MPI_ANY_SOURCE, MPI_ANY_TAG, MPI_COMM_WORLD, &Status);
-            if(Status.MPI_TAG == MPI_TAG_DONE) {
+            if(Status.MPI_TAG == MPI_TAG_DONE) 
+            {
                 MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_DONE, MPI_COMM_WORLD, &Status);
                 nfound += nFoundbyWorker.nfound;
                 options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
                 busyTasks--;
             } /* end if */
-            else if(Status.MPI_TAG == MPI_TAG_TOK_RETURN) {
+            else if(Status.MPI_TAG == MPI_TAG_TOK_RETURN) 
+            {
                 MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_DONE, MPI_COMM_WORLD, &Status);
                 nfound += nFoundbyWorker.nfound;
                 options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
                 busyTasks--;
                 havePrintToken = 1;
             } /* end else-if */
-            else if(Status.MPI_TAG == MPI_TAG_TOK_REQUEST) {
+            else if(Status.MPI_TAG == MPI_TAG_TOK_REQUEST) 
+            {
                 MPI_Recv(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_TOK_REQUEST, MPI_COMM_WORLD, &Status);
-                if(havePrintToken) {
+                if(havePrintToken) 
+                {
                     int incomingMessage;
 
                     MPI_Send(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_PRINT_TOK, MPI_COMM_WORLD);
@@ -629,11 +713,13 @@ hsize_t diff_match(hid_t file1_id,
                     busyTasks--;
                 } /* end if */
                 /* someone else must have it...wait for them to return it, then give it to the task that just asked for it. */
-                else {
+                else 
+                {
                     int source = Status.MPI_SOURCE;
                     int incomingMessage;
 
-                    do {
+                    do 
+                    {
                         MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &incomingMessage, &Status);
 
                         print_incoming_data();
@@ -647,7 +733,8 @@ hsize_t diff_match(hid_t file1_id,
                     MPI_Send(NULL, 0, MPI_BYTE, source, MPI_TAG_PRINT_TOK, MPI_COMM_WORLD);
                 } /* end else */
             } /* end else-if */
-            else if(Status.MPI_TAG == MPI_TAG_TOK_RETURN) {
+            else if(Status.MPI_TAG == MPI_TAG_TOK_RETURN) 
+            {
                 MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &Status);
                 nfound += nFoundbyWorker.nfound;
                 options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
@@ -663,7 +750,8 @@ hsize_t diff_match(hid_t file1_id,
 
                 printf("%s", data);
             } /* end else-if */
-            else {
+            else 
+            {
                 printf("ph5diff-manager: ERROR!! Invalid tag (%d) received \n", Status.MPI_TAG);
                 MPI_Abort(MPI_COMM_WORLD, 0);
             } /* end else */
@@ -702,59 +790,64 @@ hsize_t diff_match(hid_t file1_id,
  *-------------------------------------------------------------------------
  */
 
-hsize_t diff_compare (hid_t file1_id,
-                      const char *file1_name,
-                      const char *obj1_name,
-                      trav_info_t * info1,
-                      hid_t file2_id,
-                      const char *file2_name,
-                      const char *obj2_name,
-                      trav_info_t * info2,
-                      diff_opt_t * options)
+hsize_t diff_compare(hid_t file1_id,
+                     const char *file1_name,
+                     const char *obj1_name,
+                     trav_info_t *info1,
+                     hid_t file2_id,
+                     const char *file2_name,
+                     const char *obj2_name,
+                     trav_info_t *info2,
+                     diff_opt_t *options)
 {
- int f1 = 0, f2 = 0;
- hsize_t nfound = 0;
-
- ssize_t i = h5trav_getindex (info1, obj1_name);
- ssize_t j = h5trav_getindex (info2, obj2_name);
-
- if (i == -1)
- {
-  parallel_print ("Object <%s> could not be found in <%s>\n", obj1_name,
-   file1_name);
-  f1 = 1;
- }
- if (j == -1)
- {
-  parallel_print ("Object <%s> could not be found in <%s>\n", obj2_name,
-   file2_name);
-  f2 = 1;
- }
- if (f1 || f2)
- {
-  options->err_stat = 1;
-  return 0;
- }
-
- /* use the name with "/" first, as obtained by iterator function */
- obj1_name = info1->paths[i].path;
- obj2_name = info2->paths[j].path;
-
- /* objects are not the same type */
- if (info1->paths[i].type != info2->paths[j].type)
- {
-  if (options->m_verbose)
-   parallel_print("Comparison not possible: <%s> is of type %s and <%s> is of type %s\n",
-     obj1_name, get_type(info1->paths[i].type), obj2_name,
-     get_type(info2->paths[j].type));
-  options->not_cmp=1;
-  return 0;
- }
-
- nfound =
-  diff (file1_id, obj1_name, file2_id, obj2_name, options, info1->paths[i].type);
-
- return nfound;
+    int     f1 = 0;
+    int     f2 = 0;
+    hsize_t nfound = 0;
+    
+    ssize_t i = h5trav_getindex (info1, obj1_name);
+    ssize_t j = h5trav_getindex (info2, obj2_name);
+    
+    if (i == -1)
+    {
+        parallel_print ("Object <%s> could not be found in <%s>\n", obj1_name,
+            file1_name);
+        f1 = 1;
+    }
+    if (j == -1)
+    {
+        parallel_print ("Object <%s> could not be found in <%s>\n", obj2_name,
+            file2_name);
+        f2 = 1;
+    }
+    if (f1 || f2)
+    {
+        options->err_stat = 1;
+        return 0;
+    }
+    
+    /* use the name with "/" first, as obtained by iterator function */
+    obj1_name = info1->paths[i].path;
+    obj2_name = info2->paths[j].path;
+    
+    /* objects are not the same type */
+    if (info1->paths[i].type != info2->paths[j].type)
+    {
+        if (options->m_verbose)
+            parallel_print("Comparison not possible: <%s> is of type %s and <%s> is of type %s\n",
+            obj1_name, get_type(info1->paths[i].type), obj2_name,
+            get_type(info2->paths[j].type));
+        options->not_cmp=1;
+        return 0;
+    }
+    
+    nfound = diff(file1_id, 
+                  obj1_name, 
+                  file2_id, 
+                  obj2_name, 
+                  options, 
+                  info1->paths[i].type);
+    
+    return nfound;
 }
 
 
@@ -784,14 +877,15 @@ hsize_t diff(hid_t file1_id,
               diff_opt_t * options, 
               h5trav_type_t type)
 {
-    hid_t       type1_id = (-1);
-    hid_t       type2_id = (-1);
-    hid_t       grp1_id = (-1);
-    hid_t       grp2_id = (-1);
-    int ret;
+    hid_t   type1_id = (-1);
+    hid_t   type2_id = (-1);
+    hid_t   grp1_id = (-1);
+    hid_t   grp2_id = (-1);
+    int     ret;
     hsize_t nfound = 0;
     
-    switch(type) {
+    switch(type) 
+    {
        /*-------------------------------------------------------------------------
         * H5TRAV_TYPE_DATASET
         *-------------------------------------------------------------------------
@@ -801,7 +895,8 @@ hsize_t diff(hid_t file1_id,
             * verbose, always print name
             *-------------------------------------------------------------------------
             */
-            if(options->m_verbose) {
+            if(options->m_verbose) 
+            {
                 if(print_objname(options, (hsize_t)1))
                     do_print_objname("dataset", path1, path2);
                 nfound = diff_dataset(file1_id, file2_id, path1, path2, options);
@@ -813,15 +908,18 @@ hsize_t diff(hid_t file1_id,
             * disabling quiet mode
             *-------------------------------------------------------------------------
             */
-            else {
-                if(options->m_quiet == 0) {
+            else 
+            {
+                if(options->m_quiet == 0) 
+                {
                     /* shut up temporarily */
                     options->m_quiet = 1;
                     nfound = diff_dataset(file1_id, file2_id, path1, path2, options);
 
                     /* print again */
                     options->m_quiet = 0;
-                    if(nfound) {
+                    if(nfound) 
+                    {
                         if(print_objname(options,nfound))
                             do_print_objname("dataset", path1, path2);
                         nfound = diff_dataset(file1_id, file2_id, path1, path2, options);
diff --git a/tools/lib/h5diff.h b/tools/lib/h5diff.h
index 373eeed..d12031a 100644
--- a/tools/lib/h5diff.h
+++ b/tools/lib/h5diff.h
@@ -37,6 +37,8 @@ typedef struct {
     int    err_stat;  /* an error ocurred (1, error, 0, no error) */
     int    cmn_objs;  /* do we have comparable objects */
     int    not_cmp;   /* are the objects comparable */
+    int    m_contents;/* contents mode */
+    int    contents;  /* equal contents */
 } diff_opt_t;
 
 
diff --git a/tools/testfiles/h5diff_10.txt b/tools/testfiles/h5diff_10.txt
index 6a6dbae..a96e00c 100644
--- a/tools/testfiles/h5diff_10.txt
+++ b/tools/testfiles/h5diff_10.txt
@@ -12,6 +12,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -26,6 +27,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -51,8 +65,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_19.txt b/tools/testfiles/h5diff_19.txt
new file mode 100644
index 0000000..9ae1285
--- /dev/null
+++ b/tools/testfiles/h5diff_19.txt
@@ -0,0 +1,27 @@
+#############################
+Expected output for 'h5diff -v -c h5diff_basic1.h5 h5diff_empty.h5'
+#############################
+
+file1     file2
+---------------------------------------
+    x      x    /              
+    x           /g1            
+    x           /g1/d1         
+    x           /g1/d2         
+    x           /g1/dset1      
+    x           /g1/dset10     
+    x           /g1/dset3      
+    x           /g1/dset5      
+    x           /g1/dset6      
+    x           /g1/dset7      
+    x           /g1/dset8      
+    x           /g1/dset9      
+    x           /g1/fp1        
+    x           /g1/fp15       
+    x           /g1/fp16       
+    x           /g1/fp17       
+    x           /g1/fp18       
+    x           /g1/fp2        
+
+group  : </> and </>
+0 differences found
diff --git a/tools/testfiles/h5diff_600.txt b/tools/testfiles/h5diff_600.txt
index 56cc052..abaf5e7 100644
--- a/tools/testfiles/h5diff_600.txt
+++ b/tools/testfiles/h5diff_600.txt
@@ -12,6 +12,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -26,6 +27,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -51,9 +65,4 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
 h5diff error: missing file names
diff --git a/tools/testfiles/h5diff_602.txt b/tools/testfiles/h5diff_602.txt
index cc522bd..55cd0e0 100644
--- a/tools/testfiles/h5diff_602.txt
+++ b/tools/testfiles/h5diff_602.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_603.txt b/tools/testfiles/h5diff_603.txt
index 352e75e..e786d52 100644
--- a/tools/testfiles/h5diff_603.txt
+++ b/tools/testfiles/h5diff_603.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_604.txt b/tools/testfiles/h5diff_604.txt
index dde3f37..eef9847 100644
--- a/tools/testfiles/h5diff_604.txt
+++ b/tools/testfiles/h5diff_604.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_605.txt b/tools/testfiles/h5diff_605.txt
index 8047b46..1052312 100644
--- a/tools/testfiles/h5diff_605.txt
+++ b/tools/testfiles/h5diff_605.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_606.txt b/tools/testfiles/h5diff_606.txt
index d1d83a1..cdf291b 100644
--- a/tools/testfiles/h5diff_606.txt
+++ b/tools/testfiles/h5diff_606.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_611.txt b/tools/testfiles/h5diff_611.txt
index 0b148a0..07aa0cd 100644
--- a/tools/testfiles/h5diff_611.txt
+++ b/tools/testfiles/h5diff_611.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_612.txt b/tools/testfiles/h5diff_612.txt
index 2aa4804..1cc46c5 100644
--- a/tools/testfiles/h5diff_612.txt
+++ b/tools/testfiles/h5diff_612.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_613.txt b/tools/testfiles/h5diff_613.txt
index dff7f7c..194a02d 100644
--- a/tools/testfiles/h5diff_613.txt
+++ b/tools/testfiles/h5diff_613.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_614.txt b/tools/testfiles/h5diff_614.txt
index 6090f4a..1635e76 100644
--- a/tools/testfiles/h5diff_614.txt
+++ b/tools/testfiles/h5diff_614.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_615.txt b/tools/testfiles/h5diff_615.txt
index fe7f9a4..9948be5 100644
--- a/tools/testfiles/h5diff_615.txt
+++ b/tools/testfiles/h5diff_615.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_620.txt b/tools/testfiles/h5diff_620.txt
index 9221c76..03c3e53 100644
--- a/tools/testfiles/h5diff_620.txt
+++ b/tools/testfiles/h5diff_620.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_621.txt b/tools/testfiles/h5diff_621.txt
index e27b486..570a0cf 100644
--- a/tools/testfiles/h5diff_621.txt
+++ b/tools/testfiles/h5diff_621.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_622.txt b/tools/testfiles/h5diff_622.txt
index 4b6c1a1..e4afaef 100644
--- a/tools/testfiles/h5diff_622.txt
+++ b/tools/testfiles/h5diff_622.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_623.txt b/tools/testfiles/h5diff_623.txt
index f4edf37..c2e036f 100644
--- a/tools/testfiles/h5diff_623.txt
+++ b/tools/testfiles/h5diff_623.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value
diff --git a/tools/testfiles/h5diff_624.txt b/tools/testfiles/h5diff_624.txt
index babc43f..e5c6431 100644
--- a/tools/testfiles/h5diff_624.txt
+++ b/tools/testfiles/h5diff_624.txt
@@ -13,6 +13,7 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
    -r, --report            Report mode. Print differences
    -v, --verbose           Verbose mode. Print differences, list of objects
    -q, --quiet             Quiet mode. Do not do output
+   -c, --contents          Contents mode. Objects in both files must match
    -n C, --count=C         Print differences up to C number
    -d D, --delta=D         Print difference when greater than limit D
    -p R, --relative=R      Print difference when greater than relative limit R
@@ -27,6 +28,19 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
   -r Report mode: print the above plus the differences
   -v Verbose mode: print the above plus a list of objects and warnings
   -q Quiet mode: do not print output
+  -c Contents mode: objects in both files must match
+
+ Compare criteria
+
+ If no objects [obj1[obj2]] are specified, h5diff only compares objects
+   with the same absolute path in both files. However,
+   when the -c flag is present, (contents mode) the objects in file1
+   must match exactly the objects in file2
+
+ The compare criteria is:
+   1) datasets: numerical array differences 2) groups: name string difference
+   3) datatypes: the return value of H5Tequal 2) links: name string difference
+   of the linked value
 
  Return exit code:
 
@@ -52,8 +66,3 @@ usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]]
 
     to compare '/g1/dset1' and '/g1/dset2' in the same file
 
- If no objects [obj1[obj2]] are specified, h5diff only compares objects
-   with the same absolute path in both files. The compare criteria is:
-   1) datasets: numerical array differences 2) groups: name string difference
-   3) datatypes: the return value of H5Tequal 2) links: name string difference
-   of the linked value