Re: UDP recvmsg blocks after select(), 2.6 bug?

From: Mark Mielke
Date: Fri Oct 08 2004 - 10:27:21 EST


On Fri, Oct 08, 2004 at 02:10:52AM -0400, Theodore Ts'o wrote:
> On Thu, Oct 07, 2004 at 07:00:19PM -0400, Mark Mielke wrote:
> > Just say "it's a bug, but one we have chosen not to fix for practical
> > reasons." That would have kept me out of this discussion. Saying the
> > behaviour is correct and that POSIX is wrong - that raises hairs -
> > both the question kind, and the concern kind.
> Why? POSIX have gotten *lots* of things wrong in the past.
> [ non-relevant complaints about POSIX ]
> What we do when POSIX does
> something idiotic is something that has to be addressed on a
> case-by-case basis.

In this case, POSIX defines select() / blocking read() to be useful.
Linux defines it to be dangerous.

I have no question in my mind which behaviour is 'correct', in this
case. Deciding between something that works, and something that doesn't,
is a no brainer for me. Talking about performance, and so on, is just a
complete distraction. Who cares about performance when a percentage of
the time the caller will be in a confused state as a result?

I'm ok with case-by-case. I'm not ok with a generic "POSIX sucks lots -
why should we be POSIX compliant?"

Cheers,
mark

--
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and in the darkness bind them...

http://mark.mielke.cc/

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