--- ddd/show.C.orig	Wed Feb 11 17:25:07 2009
+++ ddd/show.C	Mon Sep 28 09:40:49 2009
@@ -56,6 +56,7 @@ char show_rcsid[] = 
 #include <fstream>
 #include <string.h>
 #include <errno.h>
+#include <unistd.h>
 
 #include "Xpm.h"
 #if HAVE_ATHENA