Index: trunk/ippTools/src/difftoolConfig.c
===================================================================
--- trunk/ippTools/src/difftoolConfig.c	(revision 12131)
+++ trunk/ippTools/src/difftoolConfig.c	(revision 13578)
@@ -91,7 +91,7 @@
     psMetadata *inputskyfileArgs = psMetadataAlloc();
     psMetadataAddStr(inputskyfileArgs, PS_LIST_TAIL, "-diff_id", 0,
-            "search by diff ID (required)", NULL);
+            "search by diff ID", NULL);
     psMetadataAddStr(inputskyfileArgs, PS_LIST_TAIL, "-warp_id", 0,
-            "search by warp ID (required)", NULL);
+            "search by warp ID", NULL);
     psMetadataAddStr(inputskyfileArgs, PS_LIST_TAIL, "-skycell_id", 0,
             "search by skycell ID", NULL);
@@ -132,7 +132,7 @@
             "search by warp ID", NULL);
     psMetadataAddStr(diffskyfileArgs , PS_LIST_TAIL, "-skycell_id",  0,
-            "define skycell ID (required)", NULL);
+            "define skycell ID", NULL);
     psMetadataAddStr(diffskyfileArgs, PS_LIST_TAIL, "-tess_id",  0,
-            "define tessellation ID (required)", NULL);
+            "define tessellation ID", NULL);
     psMetadataAddU64(diffskyfileArgs, PS_LIST_TAIL, "-limit",  0,
             "limit result set to N items", 0);
@@ -142,60 +142,19 @@
     psFree(now);
 
-#define PXTOOL_MODE(option, modeval, argset) \
-{ \
-    int N = 0; \
-    if ((N = psArgumentGet (argc, argv, option))) { \
-        psArgumentRemove (N, &argc, argv); \
-        if (config->mode) { \
-            psError(PS_ERR_UNKNOWN, true, "only one mode selection is allowed"); \
-            psFree(config); \
-            return NULL; \
-        } \
-        config->mode = modeval; \
-        config->args = psMemIncrRefCounter(argset); \
-    } \
-    if (!psMetadataAddMetadata(argSets, PS_LIST_TAIL, option, 0, NULL, argset)) {;\
-        psError(PS_ERR_UNKNOWN, false, "failed to add argset for %s", option); \
-    } \
-    psFree(argset); \
-}
-
     psMetadata *argSets = psMetadataAlloc();
-    // find which mode we're running under
-    PXTOOL_MODE("-definerun",       DIFFTOOL_MODE_DEFINERUN,      definerunArgs);
-    PXTOOL_MODE("-updaterun",       DIFFTOOL_MODE_UPDATERUN,      updaterunArgs);
-    PXTOOL_MODE("-addinputskyfile",  DIFFTOOL_MODE_ADDINPUTSKYFILE, addinputskyfileArgs);
-    PXTOOL_MODE("-inputskyfile",     DIFFTOOL_MODE_INPUTSKYFILE,    inputskyfileArgs);
-    PXTOOL_MODE("-todiffskyfile",    DIFFTOOL_MODE_TODIFFSKYFILE,   todiffskyfileArgs);
-    PXTOOL_MODE("-adddiffskyfile",   DIFFTOOL_MODE_ADDDIFFSKYFILE,  adddiffskyfileArgs);
-    PXTOOL_MODE("-diffskyfile",      DIFFTOOL_MODE_DIFFSKYFILE,     diffskyfileArgs);
-
-    bool argErr = false;
-    if (config->mode == DIFFTOOL_MODE_NONE) {
-        argErr = true;
-        fprintf (stderr, "mode argument is required\n");
-    } else if (! psArgumentParse(config->args, &argc, argv) || argc != 1) {
-        argErr = true;
-        fprintf (stderr, "error parsing arguments\n");
-    }
-
-    if (argErr) {
-        printf("\nPan-STARRS Difference Tool\n");
-        printf("Usage: %s <mode> [<options>]\n\n", argv[0]);
-        printf(" <mode> :\n\n"); 
-
-        psMetadataIterator *iter = psMetadataIteratorAlloc(argSets, 0, NULL);
-        psMetadataItem *item = NULL;
-        while ((item = psMetadataGetAndIncrement(iter))) {
-            if (!item->type == PS_DATA_METADATA) {
-                psAbort("all options must be specified as a metadata");
-            }
-
-            fprintf(stdout, "%s ", item->name);
-            psArgumentHelp(item->data.md);
-        }
-        psFree(iter);
-
+    psMetadata *modes = psMetadataAlloc();
+
+    PXTOOL_ADD_MODE("-definerun",       "", DIFFTOOL_MODE_DEFINERUN,      definerunArgs);
+    PXTOOL_ADD_MODE("-updaterun",       "",       DIFFTOOL_MODE_UPDATERUN,      updaterunArgs);
+    PXTOOL_ADD_MODE("-addinputskyfile", "",  DIFFTOOL_MODE_ADDINPUTSKYFILE, addinputskyfileArgs);
+    PXTOOL_ADD_MODE("-inputskyfile",    "",     DIFFTOOL_MODE_INPUTSKYFILE,    inputskyfileArgs);
+    PXTOOL_ADD_MODE("-todiffskyfile",   "",    DIFFTOOL_MODE_TODIFFSKYFILE,   todiffskyfileArgs);
+    PXTOOL_ADD_MODE("-adddiffskyfile",  "",   DIFFTOOL_MODE_ADDDIFFSKYFILE,  adddiffskyfileArgs);
+    PXTOOL_ADD_MODE("-diffskyfile",     "",      DIFFTOOL_MODE_DIFFSKYFILE,     diffskyfileArgs);
+
+    if (!pxGetOptions(stderr, argc, argv, config, modes, argSets)) {
+        psError(PS_ERR_UNKNOWN, true, "option parsing failed");
         psFree(argSets);
+        psFree(modes);
         psFree(config);
         return NULL;
@@ -203,4 +162,5 @@
 
     psFree(argSets);
+    psFree(modes);
 
     // setup search criterion
@@ -275,8 +235,4 @@
     }
 
-    // save argv/argc
-    config->argv = argv;
-    config->argc = argc;
-
     return config;
 }