From: Petr Baudis <pasky@ucw.cz>
To: Thomas Rast <trast@inf.ethz.ch>
Cc: Junio C Hamano <gitster@pobox.com>,
git@vger.kernel.org, Eric Wong <normalperson@yhbt.net>,
Marcin Owsiany <marcin@owsiany.pl>
Subject: Re: [PATCH v2 1/2] perl: redirect stderr to /dev/null instead of closing
Date: Sat, 6 Apr 2013 12:34:26 +0200 [thread overview]
Message-ID: <20130406103426.GE6137@machine.or.cz> (raw)
In-Reply-To: <878v4wrsj7.fsf@linux-k42r.v.cablecom.net>
On Sat, Apr 06, 2013 at 10:07:40AM +0200, Thomas Rast wrote:
> The manpage for dup2 does, however, say
>
> If newfd was open, any errors that would have been reported at
> close(2) time are lost. A careful programmer will not use dup2() or
> dup3() without closing newfd first.
>
> which is probably what you were referring to.
Yes, that's probably one reason why I had this stuck in my mind (though,
how often does anyone bother to detect errors on close()...? ;-).
Funnily enough, POSIX.2008 specifies that if closing newfd would fail,
dup2() reports EIO and newfd is not closed, eliminating this problem.
The manpage does not cover this; well, that's fair enough as Linux just
doesn't care and never does that if I didn't miss anything in the code.
--
Petr "Pasky who might even send
a patch, but the matter is
oh so obscure" Baudis
next prev parent reply other threads:[~2013-04-06 17:00 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-03 22:26 [PATCH] perl: redirect stderr to /dev/null instead of closing Thomas Rast
2013-04-04 1:16 ` Eric Wong
2013-04-04 20:41 ` [PATCH v2 1/2] " Thomas Rast
2013-04-04 21:14 ` Eric Wong
2013-04-05 14:48 ` Petr Baudis
2013-04-05 18:57 ` Junio C Hamano
2013-04-05 23:34 ` Petr Baudis
2013-04-06 8:07 ` Thomas Rast
2013-04-06 10:34 ` Petr Baudis [this message]
2013-04-04 20:41 ` [PATCH v2 2/2] t9700: do not close STDERR Thomas Rast
2013-04-04 21:11 ` Jonathan Nieder
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