Index: trunk/psphot/src/psphotSetMaskBits.c
===================================================================
--- trunk/psphot/src/psphotSetMaskBits.c	(revision 18469)
+++ trunk/psphot/src/psphotSetMaskBits.c	(revision 18469)
@@ -0,0 +1,32 @@
+# include "psphotInternal.h"
+
+// XXX Should it be an error for any of these to not exist?
+
+// This function is called by the stand-alone psphot program to set the mask values in the
+// config file.  It sets the named mask values MASK.PSPHOT and MARK.PSPHOT in the PSPHOT
+// recipe.  Functions or programs which call psphotReadout as a library function must set these
+// named mask values in the PSPHOT recipe on their own.
+
+bool psphotSetMaskBits (pmConfig *config) {
+
+    psMaskType maskValue;
+    psMaskType markValue;
+
+    if (!pmConfigMaskSetBits (&maskValue, &markValue, config)) {
+	psError (PS_ERR_UNKNOWN, true, "Unable to define the mask bit values");
+	return false;
+    }
+
+    // select the current recipe
+    psMetadata *recipe = psMetadataLookupPtr (NULL, config->recipes, PSPHOT_RECIPE);
+    if (!recipe) {
+        psError(PSPHOT_ERR_CONFIG, false, "missing recipe %s", PSPHOT_RECIPE);
+        return false;
+    }
+
+    // set maskValue and markValue in the psphot recipe
+    psMetadataAddU8 (recipe, PS_LIST_TAIL, "MARK.PSPHOT", PS_META_REPLACE, "user-defined mask", markValue);
+    psMetadataAddU8 (recipe, PS_LIST_TAIL, "MASK.PSPHOT", PS_META_REPLACE, "user-defined mask", maskValue);
+
+    return true;
+}