From owner-freebsd-current  Sat Nov 30  6:17:14 2002
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From: "Brian Smith" <dbsoft@technologist.com>
To: "Terry Lambert" <tlambert2@mindspring.com>
Cc: "current@FreeBSD.ORG" <current@FreeBSD.ORG>
Date: Sat, 30 Nov 2002 08:17:15 -0600 (CST)
Reply-To: "Brian Smith" <dbsoft@technologist.com>
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Subject: Re: Are SysV semaphores thread-safe on CURRENT?
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On Mon, 18 Nov 2002 22:05:34 -0800, Terry Lambert wrote:

>Use mmap of a backing-store file, and then use file locking to
>do record locking in the shared memory segment.

Ok, I did this, and it actually works considerably better than
the SysV shared memory.  However flock() has the same problem
as the SysV semaphores, where they block the entire process,
allowing the same deadlock situation to occur.  Has this flock()
behavior changed in CURRENT?  

It seems like this behavior is much more likely to change than
the SysV code.

Thanks!

Brian Smith


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