From: "H. Peter Anvin" <hpa@zytor.com>
To: Badari Pulavarty <pbadari@us.ibm.com>
Cc: netdev@vger.kernel.org, lkml <linux-kernel@vger.kernel.org>,
Christoph Lameter <clameter@sgi.com>,
Andrew Morton <akpm@linux-foundation.org>
Subject: Re: select(0, ..) is valid ?
Date: Tue, 15 May 2007 10:42:55 -0700 [thread overview]
Message-ID: <4649F11F.3040807@zytor.com> (raw)
In-Reply-To: <1179250159.2836.117.camel@dyn9047017100.beaverton.ibm.com>
Badari Pulavarty wrote:
> Hi,
>
> Is select(0, ..) is a valid operation ?
>
> I see that there is no check to prevent this or return
> success early, without doing any work. Do we need one ?
>
> slub code is complaining that we are doing kmalloc(0).
>
select(0, ...) is valid, and is functionally equivalent to
select(..., NULL, NULL, NULL, ...); except that any nonzero fdsets get
zeroed on return. As such, the only thing that can interrupt it is the
timeout, or a signal.
-hpa
next prev parent reply other threads:[~2007-05-15 17:45 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-05-15 17:29 select(0, ..) is valid ? Badari Pulavarty
2007-05-15 17:34 ` Mark Glines
2007-05-15 17:36 ` Jiri Slaby
2007-05-15 17:42 ` H. Peter Anvin [this message]
2007-05-15 17:43 ` Alan Cox
2007-05-15 17:44 ` Andrew Morton
2007-05-15 17:57 ` Badari Pulavarty
2007-05-15 18:10 ` Christoph Lameter
2007-05-15 18:30 ` Andrew Morton
2007-05-15 18:36 ` Christoph Lameter
2007-05-15 18:44 ` Hugh Dickins
2007-05-16 15:37 ` Anton Blanchard
2007-05-17 0:59 ` Badari Pulavarty
2007-05-22 14:16 ` Steve Fox
2007-05-22 14:34 ` Nishanth Aravamudan
2007-05-22 17:49 ` Steve Fox
2007-05-18 13:21 ` Andi Kleen
2007-05-22 1:21 ` Nish Aravamudan
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