From owner-freebsd-hackers@FreeBSD.ORG  Thu Apr  7 14:24:42 2005
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Date: Thu, 7 Apr 2005 09:24:41 -0500 (CDT)
From: Zera William Holladay <zholla1@uic.edu>
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Subject: Re: Kernel [memory] tweaking question
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On Thu, 7 Apr 2005, Peter Jeremy wrote:
> These are all reasonably well documented in sys/conf/NOTES.  If you
> want more detail, try a SystemV-oriented Unix book
>
> Close - they only control SystemV shared memory.  Sane shared memory
> is available via mmap(2).  SystemV semaphores are controlled via
> SEMxxx options.  Posix semaphores are listed as 'experimental'.

Is there any chance that POSIX semaphores will be anything other than
experimental in the future, or is there no interest?  Further, the man
page indicates that the FreeBSD, POSIX semaphore implementation is not
capable of supporting multiple process semaphores.  I saw a similar note
on a Linux man page.  I think this is a shame, since POSIX semaphores seem
to be well designed (from a user point of view) compared to SYSV
semaphores, which are a total mess.

-Zera