From 963a74f13cfe27380aa14da7b69121a00cb7415a Mon Sep 17 00:00:00 2001
From: Konstantin Belousov <kib@FreeBSD.org>
Date: Mon, 27 Feb 2012 20:52:20 +0000
Subject: [PATCH] Fix a race in top non-interactive mode.  Use plain sleep(3)
 call instead of arming timer and then pausing.  If SIGALRM is delivered
 before pause(3) is entered, top hangs.

Submitted by:	Andrey Zonov <andrey zonov org>
MFC after:	1 week
---
 contrib/top/top.c | 16 +---------------
 1 file changed, 1 insertion(+), 15 deletions(-)

diff --git a/contrib/top/top.c b/contrib/top/top.c
index e7e27d54a97..aaab027ef09 100644
--- a/contrib/top/top.c
+++ b/contrib/top/top.c
@@ -70,7 +70,6 @@ int pcpu_stats = No;
 
 /* signal handling routines */
 sigret_t leave();
-sigret_t onalrm();
 sigret_t tstop();
 #ifdef SIGWINCH
 sigret_t winch();
@@ -723,12 +722,7 @@ char *argv[];
 	    no_command = Yes;
 	    if (!interactive)
 	    {
-		/* set up alarm */
-		(void) signal(SIGALRM, onalrm);
-		(void) alarm((unsigned)delay);
-    
-		/* wait for the rest of it .... */
-		pause();
+		sleep(delay);
 	    }
 	    else while (no_command)
 	    {
@@ -1174,11 +1168,3 @@ int status;
     exit(status);
     /*NOTREACHED*/
 }
-
-sigret_t onalrm()	/* SIGALRM handler */
-
-{
-    /* this is only used in batch mode to break out of the pause() */
-    /* return; */
-}
-