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Date: Tue, 26 Feb 2002 19:14:09 +0100
From: Andreas Ferber <aferber@techfak.uni-bielefeld.de>
To: linux-kernel@vger.kernel.org
Subject: Re: ext3 and undeletion
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In-Reply-To: <20020226173822.GN4393@matchmail.com>; from mfedyk@matchmail.com on Tue, Feb 26, 2002 at 09:38:22AM -0800
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On Tue, Feb 26, 2002 at 09:38:22AM -0800, Mike Fedyk wrote:
> 
> Basically, it would only move the files to the undelete area if the link
> count == 1.  If you just decremented the link, then unlink() in glibc would
> work as it does now.

Always racy if done in userspace, unless you introduce a centralised
"unlink daemon" (hope no glibc developer reads that, they might be
tempted to implement such an abomination...):

     proc1       proc2
   --------------------
    stat()
                stat()
    unlink()
                unlink()

*kaboom*, blackhole opens, file is gone.

/If/ you start doing such a mess (personally I don't want undeletion
anyways), please do it at least in a correct way.

Andreas
-- 
       Andreas Ferber - dev/consulting GmbH - Bielefeld, FRG
     ---------------------------------------------------------
         +49 521 1365800 - af@devcon.net - www.devcon.net
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