$NetBSD$

--- libpnmrw.c.orig	1995-08-16 22:24:26.000000000 +0000
+++ libpnmrw.c
@@ -28,6 +28,7 @@
 #endif
 
 #include <stdio.h>
+#include <errno.h>
 #include "libpnmrw.h"
 
 /* if don't have string.h, try strings.h */
@@ -126,8 +127,9 @@ static void
   pm_perror( reason )
 char* reason;
 {
+#if !defined(__NetBSD__) && !defined(__DragonFly__) && !defined(__FreeBSD__)
   extern char* sys_errlist[];
-  extern int errno;
+#endif
   char* e;
 
   e = sys_errlist[errno];
