From 8025c44b00f74e8dd65b526b5a7fa7cbf805b2a5 Mon Sep 17 00:00:00 2001
From: Dima Dorfman <dd@FreeBSD.org>
Date: Wed, 2 Oct 2002 03:24:27 +0000
Subject: [PATCH] Add an -o option to exit after receiving one reply.  This can
 be used to test whether a link is live.

PR:		38573
Submitted by:	David Taylor <davidt@yadt.co.uk>
Obtained from:	NetBSD
---
 sbin/ping/ping.8 |  6 ++++--
 sbin/ping/ping.c | 11 ++++++++---
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/sbin/ping/ping.8 b/sbin/ping/ping.8
index 9f05cffa8312..b71d13884241 100644
--- a/sbin/ping/ping.8
+++ b/sbin/ping/ping.8
@@ -32,7 +32,7 @@
 .\"     @(#)ping.8	8.2 (Berkeley) 12/11/93
 .\" $FreeBSD$
 .\"
-.Dd September 25, 2001
+.Dd October 2, 2002
 .Dt PING 8
 .Os
 .Sh NAME
@@ -42,7 +42,7 @@
 packets to network hosts
 .Sh SYNOPSIS
 .Nm
-.Op Fl AQRadfnqrv
+.Op Fl AQRadfnoqrv
 .Op Fl c Ar count
 .Op Fl i Ar wait
 .Op Fl l Ar preload
@@ -160,6 +160,8 @@ This flag only applies if the ping destination is a multicast address.
 .It Fl n
 Numeric output only.
 No attempt will be made to lookup symbolic names for host addresses.
+.It Fl o
+Exit successfully after receiving one reply packet.
 .It Fl p Ar pattern
 You may specify up to 16
 .Dq pad
diff --git a/sbin/ping/ping.c b/sbin/ping/ping.c
index ca7a69bc3945..99a4c0e470fe 100644
--- a/sbin/ping/ping.c
+++ b/sbin/ping/ping.c
@@ -137,6 +137,7 @@ int options;
 #endif /*IPSEC*/
 #define	F_TTL		0x8000
 #define	F_MISSED	0x10000
+#define	F_ONCE		0x20000
 
 /*
  * MAX_DUP_CHK is the number of bits in received table, i.e. the maximum
@@ -242,7 +243,7 @@ main(argc, argv)
 
 	datap = &outpack[MINICMPLEN + PHDR_LEN];
 	while ((ch = getopt(argc, argv,
-		"AI:LQRS:T:c:adfi:l:m:np:qrs:t:v"
+		"AI:LQRS:T:c:adfi:l:m:nop:qrs:t:v"
 #ifdef IPSEC
 #ifdef IPSEC_POLICY_IPSEC
 		"P:"
@@ -320,6 +321,9 @@ main(argc, argv)
 		case 'n':
 			options |= F_NUMERIC;
 			break;
+		case 'o':
+			options |= F_ONCE;
+			break;
 		case 'p':		/* fill buffer with user pattern */
 			options |= F_PINGFILLED;
 			fill((char *)datap, optarg);
@@ -696,7 +700,8 @@ main(argc, argv)
 				t = &now;
 			}
 			pr_pack((char *)packet, cc, &from, t);
-			if (npackets && nreceived >= npackets)
+			if (options & F_ONCE && nreceived ||
+			    npackets && nreceived >= npackets)
 				break;
 		}
 		if (n == 0 || options & F_FLOOD) {
@@ -1441,7 +1446,7 @@ static void
 usage()
 {
 	(void)fprintf(stderr, "%s\n%s\n%s\n",
-"usage: ping [-AQRadfnqrv] [-c count] [-i wait] [-l preload] [-m ttl]",
+"usage: ping [-AQRadfnoqrv] [-c count] [-i wait] [-l preload] [-m ttl]",
 "            [-p pattern] "
 #ifdef IPSEC
 #ifdef IPSEC_POLICY_IPSEC