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From: Terry Lambert <terry@lambert.org>
Message-Id: <199610311843.LAA25711@phaeton.artisoft.com>
Subject: Re: Zombie processes
To: gjennejohn@frt.dec.com
Date: Thu, 31 Oct 1996 11:43:13 -0700 (MST)
Cc: ormonde@trem.cnt.org.br, hackers@FreeBSD.org
In-Reply-To: <9610311315.AA16026@cssmuc.frt.dec.com> from "garyj@frt.dec.com" at Oct 31, 96 02:15:02 pm
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> >   Is there any way to remove the zombie process from the system
> > without blocking the parent process ?
> 
> try using a handler for SIGCHLD and do the wait there. It might be
> even better to use waitpid.

Use waitpid, wait3, or wait4.  Specify the option value WNOHANG, and
the calls will return 0 if no processes are zombied.

Alternately, set a signal handler of SIG_IGN for SIGCHLD.  This is
guaranteed to not create zombies in the first place for all POSIX
compliant or conformant OS's.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.