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Date: Fri, 23 Nov 2012 18:29:37 +0100
From: Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
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Subject: Re: Possible race in SYSV IPC (semaphores)
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On Nov 23 17:16, Lavrentiev, Anton (NIH/NLM/NCBI) [C] wrote:
> > This should avoid the race (*and* work...)
> > Please give it a try.
> 
> Thanks!  I've tried both patches (pipe race + semadj), and they do seem to work!

Thanks for testing.

> Although (not being a party pooper :-), I think that all the logic
> around "pipe_instance" can now be dropped entirely, and benefit from eliminating
> an unnecessary synchronization point (pipe_instance is now only used
> for logging a proper pipe ID, which is not even seen in regular use,
> and for an assert(), which again is only there in debug mode builds).
> So there is no need to arrange Enter'ing/Leave'ing of the critical section
> to do just the hidden things, yet the working code would be a bit cleaner.

I agree.  I'll do that in the next couple of days.


Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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