$OpenBSD: patch-src_cflex_c,v 1.5 2009/09/01 14:25:15 okan Exp $
--- src/cflex.c.orig	Sat Apr 11 16:00:11 2009
+++ src/cflex.c	Thu May 28 17:32:35 2009
@@ -4890,7 +4890,7 @@ static void yy_load_buffer_state  (void)
 }
 
 #ifndef __cplusplus
-extern int isatty (int );
+#include <unistd.h>
 #endif /* __cplusplus */
     
 /* Initializes or reinitializes a buffer.