Index: trunk/Ohana/src/opihi/cmd.astro/flux.c
===================================================================
--- trunk/Ohana/src/opihi/cmd.astro/flux.c	(revision 27491)
+++ trunk/Ohana/src/opihi/cmd.astro/flux.c	(revision 27611)
@@ -29,5 +29,9 @@
   ymax = 0;
   for (i = 0; i < 4; i++) {
-    fscanf (f, "%lf %lf", &x[i], &y[i]);
+    if (fscanf (f, "%lf %lf", &x[i], &y[i]) != 2) {
+      fprintf (stderr, "error reading coordinates from %s\n", argv[2]);
+      fclose (f);
+      return (FALSE);
+    }
     xmin = MAX (0, MIN (xmin, x[i] - 1));
     ymin = MAX (0, MIN (ymin, y[i] - 1));