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Date: Wed, 13 Apr 2011 16:23:01 +0300
From: Nikos Vassiliadis <nvass@gmx.com>
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To: Bastien Semene <bsemene@cyanide-studio.com>
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Cc: freebsd-questions@freebsd.org
Subject: Re: lockf command
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On 4/13/2011 12:08 PM, Bastien Semene wrote:
> I wish that if command #2 can't acquire the lock, lockf exits (exit 0
> would be nice).
> If I set -t 1, lockf is quite what I'm waiting for. But I like to do
> this in a clear way : if it can't acquire the lock it exits, no timeout
> wait.
>
> Am I misunderstanding something ? What should I change ?
>

You should use -t0, something like:
> lab# lockf -t 0 /tmp/lock /bin/csh
> You have mail.
> lab# lockf -t 0 /tmp/lock /bin/csh
> lockf: /tmp/lock: already locked
> lab# echo $?
> 75
> lab#

HTH, Nikos