Index: trunk/ppImage/src/ppImageDefineFile.c
===================================================================
--- trunk/ppImage/src/ppImageDefineFile.c	(revision 13531)
+++ trunk/ppImage/src/ppImageDefineFile.c	(revision 13531)
@@ -0,0 +1,55 @@
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+# include "ppImage.h"
+
+bool ppImageDefineFile (pmConfig *config, pmFPA *input, char *filerule, char *argname, pmFPAfileType type) {
+
+    bool status;
+    pmFPAfile *file;
+
+    // look for the file on the argument list
+    file = pmFPAfileDefineFromArgs  (&status, config, filerule, argname);
+    if (!status) {
+	psError (PS_ERR_UNKNOWN, false, "failed to load find definition");
+	return false;
+    }
+    if (file) {
+	if (file->type != type) {
+	    psError(PS_ERR_IO, true, "%s is not of type %s", filerule, pmFPAfileStringFromType (type));
+	    return false;
+	}
+	return true;
+    }
+
+    // look for the file in the camera config table
+    file = pmFPAfileDefineFromConf  (&status, config, filerule);
+    if (!status) {
+	psError (PS_ERR_UNKNOWN, false, "failed to load find definition");
+	return false;
+    }
+    if (file) {
+	if (file->type != type) {
+	    psError(PS_ERR_IO, true, "%s is not of type %s", filerule, pmFPAfileStringFromType (type));
+	    return false;
+	}
+	return true;
+    }
+
+    // look for the file to be loaded from the detrend database
+    pmFPAfileDefineFromDetDB (&status, config, filerule, input, type);
+    if (!status) {
+	psError (PS_ERR_UNKNOWN, false, "failed to load find definition");
+	return false;
+    }
+    if (file) {
+	if (file->type != type) {
+	    psError(PS_ERR_IO, true, "%s is not of type %s", filerule, pmFPAfileStringFromType (type));
+	    return false;
+	}
+	return true;
+    }
+    return false;
+}
+