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From: "Manfred Spraul" <manfred@colorfullife.com>
To: "Stelian Pop" <stelian.pop@fr.alcove.com>
Cc: <linux-kernel@vger.kernel.org>
In-Reply-To: <000d01c0b3c7$e232ae90$5517fea9@local> <20010326165425.G15689@come.alcove-fr>
Subject: Re: Use semaphore for producer/consumer case...
Date: Mon, 26 Mar 2001 19:12:55 +0200
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From: "Stelian Pop" <stelian.pop@fr.alcove.com>
> >
> > That doesn't work, at least the i386 semaphore implementation
doesn't
> > support semaphore counts < 0.
>
> Does that mean that kernel semaphore can not be used for something
> else than mutual exclusion ?
>
It's a bit better: counts >= 0 are supported, i.e. you can call up()
before down(), and that's used in several places.

The for loop that Nigel proposed should solve your problem. Multiple
up's are handled correctly.

--
    Manfred

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