$NetBSD$

--- src/callproc.c.orig	2006-01-04 16:05:18.000000000 +0000
+++ src/callproc.c
@@ -24,8 +24,10 @@ Boston, MA 02111-1307, USA.  */
 
 #include <config.h>
 #include <stdio.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
 
-extern int errno;
 extern char *strerror ();
 
 /* Define SIGCHLD as an alias for SIGCLD.  */
