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To: linux-kernel@vger.kernel.org
Subject: Re: PROBLEM: I/O system call never returns if file desc is closed in the
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From: Florian Weimer <Florian.Weimer@RUS.Uni-Stuttgart.DE>
Date: 07 Jun 2001 06:24:38 +0200
In-Reply-To: <p05100310b744a22f02a6@[192.109.102.42]> (Matthias Urlichs's message of "Thu, 7 Jun 2001 05:25:30 +0200")
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Matthias Urlichs <smurf@noris.de> writes:

> Select is defined as to return, with the appropriate bit set, if/when
> a nonblocking read/write on the file descriptor won't block. You'd get
> EBADF in this case, therefore causing the select to return would be a
> Good Thing.

How do you avoid race conditions if more than one thread is creating
file descriptors?  I think you can only do that under very special
circumstances, and it definitely requires some synchronization.

-- 
Florian Weimer 	                  Florian.Weimer@RUS.Uni-Stuttgart.DE
University of Stuttgart           http://cert.uni-stuttgart.de/
RUS-CERT                          +49-711-685-5973/fax +49-711-685-5898