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To: Bill Fenner <fenner@parc.xerox.com>
cc: cvs-etc@freebsd.org, cvs-all@freebsd.org, cvs-committers@freebsd.org
Subject: Re: cvs commit: src/etc rc 
In-reply-to: Your message of "Tue, 03 Jun 1997 08:32:05 PDT."
             <97Jun3.083213pdt.177489@crevenia.parc.xerox.com> 
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Date: Tue, 03 Jun 1997 21:01:14 +0100
From: Brian Somers <brian@awfulhak.org>
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> Don't forget that if you use a flock(), there is a race condition when
> two seperate processes are checking to see if the daemon is running
> where one process may think it's not running (its attempt to lock the
> pidfile succeeds) and the other process thinks it's running (since its
> attempt fails since the first process hadn't released its lock yet).

Not true.  The lock is a write lock.  The check is a read lock.  A
read lock won't affect another read lock.

Remember, you can do just about anything, given the ability to both
read lock and write lock.

>   Bill
> 

-- 
Brian <brian@awfulhak.org>, <brian@freebsd.org>
      <http://www.awfulhak.org>
Don't _EVER_ lose your sense of humour....