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To: Peter Edwards <peter.edwards@openet-telecom.com>
References: <Pine.NEB.3.96L.1040131234955.17012E-100000@fledge.watson.org>
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From: des@des.no (Dag-Erling =?iso-8859-1?q?Sm=F8rgrav?=)
Date: Tue, 03 Feb 2004 17:37:11 +0100
In-Reply-To: <401FCCBE.2010008@openet-telecom.com> (Peter Edwards's message
 of "Tue, 03 Feb 2004 16:30:54 +0000")
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cc: Robert Watson <rwatson@FreeBSD.org>
cc: current@FreeBSD.org
Subject: Re: Coalescing pipe allocation
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Peter Edwards <peter.edwards@openet-telecom.com> writes:
> How would one "shut down" one direction of the pipe and still maintain
> the other? I don't know how I can signal my intention not to read or
> write to the end I leave open...

man 2 shutdown

> Is this portability issue so ridiculously out of date that the comment
> in the pipe(2) manpage should be removed, or at least toned down?

No, POSIX only guarantees the traditional behaviour.  Bi-directional
pipes are a non-portable BSDism.

>                                                                   It
> seems silly to incur the costs of implementation you've mentioned and
> then recommend that the feature not be used.

It can still be useful for programs in the base system, which do not
need to be unconditionally portable to non-BSD systems.

DES
--=20
Dag-Erling Sm=F8rgrav - des@des.no