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Date: Mon, 20 Jul 2009 14:36:08 +0200
From: Ed Schouten <ed@80386.nl>
To: Benjamin Kaduk <kaduk@MIT.EDU>
Message-ID: <20090720123607.GI68469@hoeg.nl>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: add missing content to locking.9 ?
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Hi Benjamin,

* Benjamin Kaduk <kaduk@MIT.EDU> wrote:
> +.Tn POSIX
> +semaphores provide ...

it looks like you described the semaphores that are used in userspace.
The Semaphores section of the locking(9) man page should describe
in-kernel semaphores (kern_sema.c). They are implemented by a mutex and
a conditional variable.

Even though it's nice to have some utility functions in our kernel, I
always wondered why we have them. There isn't a lot of code in the tree
that uses them...

--=20
 Ed Schouten <ed@80386.nl>
 WWW: http://80386.nl/

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