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Message-ID: <4914A1FA.5000208@codemonkey.ws>
Date: Fri, 07 Nov 2008 14:15:54 -0600
From: Anthony Liguori <anthony@codemonkey.ws>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] bug writing pidfile under unix (and fix)
References: <20081107170215.7ca43a08@dgym.ktulu>
	<200811071756.12371.paul@codesourcery.com>
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To: qemu-devel@nongnu.org
Cc: Jim Bailey <dgym.bailey@gmail.com>

Paul Brook wrote:
> On Friday 07 November 2008, Jim Bailey wrote:
>   
>> Hello,
>>
>> In qemu_create_pidfile (osdep.c:229) the current pid and a newline is
>> written to the pidfile. However, the pidfile isn't truncated, so if it
>> is longer than the length of the pid and the newline character you get
>> trailing junk that can really mess up scripts.
>>     
>
> Shouldn't we just open with O_TRUNC ?
>   

Definitely.

> I also notice that we're not removing the file when we exit.
>   

It's not terribly useful to remove the file but it couldn't hurt.  An 
advisory lock is used to ensure that only one process is running at a 
given time.

Regards,

Anthony Liguori

> Paul
>
>
>