--- rat/config_unix.h.orig	Sat Nov 27 18:27:56 1999
+++ rat/config_unix.h	Sat Nov 27 18:33:33 1999
@@ -17,6 +17,7 @@
 
 #include <limits.h>
 #include <sys/types.h>
+#include <sys/signal.h>
 #include <sys/time.h>
 #include <sys/resource.h>