From 525c9d6e37d1dea2b3b16cac7bb3a877323854c3 Mon Sep 17 00:00:00 2001
From: cgd <cgd@NetBSD.org>
Date: Tue, 4 Jun 1996 20:09:03 +0000
Subject: [PATCH] if doing 'netstat -I <intf> -w <delay>', and netstat can't
 find an interface of the given name, print an error message and exit. This
 whole section of code needs to be re-thought, if interfaces can be
 dynamically added or removed.

---
 usr.bin/netstat/if.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/usr.bin/netstat/if.c b/usr.bin/netstat/if.c
index 11884bd1eb85..051a83d48158 100644
--- a/usr.bin/netstat/if.c
+++ b/usr.bin/netstat/if.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: if.c,v 1.16 1996/05/07 05:30:45 thorpej Exp $	*/
+/*	$NetBSD: if.c,v 1.17 1996/06/04 20:09:03 cgd Exp $	*/
 
 /*
  * Copyright (c) 1983, 1988, 1993
@@ -37,7 +37,7 @@
 #if 0
 static char sccsid[] = "from: @(#)if.c	8.2 (Berkeley) 2/21/94";
 #else
-static char *rcsid = "$NetBSD: if.c,v 1.16 1996/05/07 05:30:45 thorpej Exp $";
+static char *rcsid = "$NetBSD: if.c,v 1.17 1996/06/04 20:09:03 cgd Exp $";
 #endif
 #endif /* not lint */
 
@@ -283,7 +283,7 @@ sidewaysintpr(interval, off)
 	lastif = iftot;
 	sum = iftot + MAXIF - 1;
 	total = sum - 1;
-	interesting = iftot;
+	interesting = (interface == NULL) ? iftot : NULL;
 	for (off = firstifnet, ip = iftot; off;) {
 		if (kread(off, (char *)&ifnet, sizeof ifnet))
 			break;
@@ -298,6 +298,11 @@ sidewaysintpr(interval, off)
 			break;
 		off = (u_long)ifnet.if_list.tqe_next;
 	}
+	if (interesting == NULL) {
+		fprintf(stderr, "%s: %s: unknown interface\n",
+		    __progname, interface);
+		exit(1);
+	}
 	lastif = ip;
 
 	(void)signal(SIGALRM, catchalarm);