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From: "David Schwartz" <davids@webmaster.com>
To: "David Wragg" <dpw@doc.ic.ac.uk>, <tytso@mit.edu>
Cc: <linux-kernel@vger.kernel.org>
Subject: RE: What protects f_pos?
Date: Sun, 12 Nov 2000 14:27:54 -0800
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> tytso@mit.edu writes:
> > This looks like it's a bug to me....  although if you have multiple
> > threads hitting a file descriptor at the same time, you're pretty much
> > asking for trouble.
>
> Yes, I haven't been able to come up with an example that might trigger
> this that wasn't dubious to begin with.  I'll raise this again at a
> convenient time during 2.5.
>
> David

	Suppose you had a multithreaded program that used a configuration file with
a group of fixed-length blocks indicating what work it had to do. Each
thread read a block from the file and then did the work. One might think
that there's no need to protect the file descriptor with a mutex.

	DS

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