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From: Ulrich Drepper <drepper@redhat.com>
To: Eric Blake <ebb9@byu.net>
Cc: Davide Libenzi <davidel@xmailserver.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	bug-coreutils@gnu.org, bug-gnulib@gnu.org,
	Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH] open: introduce O_NOSTD
Date: Thu, 27 Aug 2009 07:22:19 -0700	[thread overview]
Message-ID: <4A96969B.2090004@redhat.com> (raw)
In-Reply-To: <4A968FF8.8050109@byu.net>

On 08/27/2009 06:54 AM, Eric Blake wrote:
> I hope that my example shows why doing it in the kernel is desirable -
> there is no safe way to keep the pre-O_CLOEXEC efficiency using just the
> library, but there IS a way to do it with kernel support:

You're describing a very special case where the performance implications 
are really minimal and try to argue that is a good enough reason?  I 
don't think so.

If a program really has to do thousands of these safe open calls then it 
can invest time into opening /dev/null for any of the unallocated 
descriptors < 3.  You can even embed this logic in the safer_open function.

-- 
➧ Ulrich Drepper ➧ Red Hat, Inc. ➧ 444 Castro St ➧ Mountain View, CA ❖

  reply	other threads:[~2009-08-27 14:22 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-08-24 12:22 [RFC] new open flag O_NOSTD Eric Blake
2009-08-25 12:16 ` [PATCH] open: introduce O_NOSTD Eric Blake
2009-08-25 21:53   ` Davide Libenzi
2009-08-27 13:54     ` Eric Blake
2009-08-27 14:22       ` Ulrich Drepper [this message]
2009-08-28 12:28         ` Eric Blake
2009-08-27 14:35       ` Florian Weimer
2009-08-28 12:45         ` Eric Blake
2009-08-28 12:52           ` Florian Weimer
2009-08-28 12:58             ` Eric Blake
2009-08-28 13:04             ` Eric Blake
2009-08-27 22:55       ` Davide Libenzi
2009-08-27 23:11         ` Ulrich Drepper
2009-08-30 11:12 ` [RFC] new open flag O_NOSTD James Youngman
2009-08-30 11:18   ` Jim Meyering

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