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Date: Mon, 01 Jun 2009 22:17:48 +0100
From: Bruce Simpson <bms@FreeBSD.org>
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To: Jilles Tjoelker <jilles@stack.nl>
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Cc: Vlad Galu <dudu@dudu.ro>, freebsd-stable@freebsd.org
Subject: Re: Unnamed POSIX shared semaphores
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Jilles Tjoelker wrote:
> If process-shared semaphores really work, then the above structure is
> not a pathological case. Effectively, sem_t is carved in stone. So
> process-private semaphores should continue to have most of their stuff
> in a separately allocated structure, to preserve flexibility.
>   

There was an inadvertent race in FreeBSD's POSIX semaphores which I 
fixed in HEAD and STABLE about 6 weeks before 7.2 was released.

I believe process-shared POSIX semaphores now work -- the Python 
'multiprocessing' regression test now runs to completion with no errors 
on both HEAD and STABLE.

cheers,
BMS