--- AppController.m.orig	Sat Oct 19 16:25:11 2013
+++ AppController.m	Sat Oct 19 16:26:08 2013
@@ -29,7 +29,7 @@
     sscanf(buffer,"%f %f %f",&r,&g,&b);
     /* printf("%f %f %f\n",r,g,b); */
 
-    if (f=fopen(XCONF,"rw")) {
+    if ((f=fopen(XCONF,"rw")) != NULL) {
 	fclose(f);
 	[button setEnabled:YES];
     }