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Date: Mon, 8 Jul 1996 09:10:53 -0400 (EDT)
From: "Ron G. Minnich" <rminnich@Sarnoff.COM>
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Subject: Re: filemalloc etc. for shared memory between processes
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> 	I wonder how one should properly implement locking of memory
> 	regions in this case. Will appropriate fcntl(2) be
> 	enough?

no, you use the fastlock() i posted earlier. fcntl is probably the worst 
way there is to lock shared regions. You want memory-value-based locking 
so you can use compare-and-swap (or equivalent).

ron