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Date: Thu, 11 Sep 2003 22:02:00 -0700
From: Greg Stein <gstein@lyra.org>
To: Aaron Bannert <aaron@clove.org>
Cc: dev@apr.apache.org
Subject: Re: remove nested mutexes?
Message-ID: <20030911220200.C27308@lyra.org>
Mail-Followup-To: Aaron Bannert <aaron@clove.org>, dev@apr.apache.org
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 from aaron@clove.org on Thu, Sep 11, 2003 at 10:01:00PM -0700

On Thu, Sep 11, 2003 at 10:01:00PM -0700, Aaron Bannert wrote:
> I propose we do one of the following.
> 
> 1) Remove nested muxtes, meaning all mutexes become non-nested (they 
> will
> deadlock whenever the same thread locks twice).
>    Pros: Nested mutexes are lame and are unnecessary. The current 
> implementation
>              in APR is broken.
>    Cons: Some applications may be written to rely on nested mutexes.

I've written applications like this. One thread will create a mutex, stash
that away in a global, or somesuch, and then lock the thing *twice*. When
another thread wants the first one to resume, it unlocks the mutex.

If we have another way for a thread to block, then have another thread say
"okay. go ahead and proceed", then I'm all for removing nested mutexes.

Cheers,
-g

-- 
Greg Stein, http://www.lyra.org/