Message-ID: <4164530F.7020605@nortelnetworks.com>
Date: Wed, 06 Oct 2004 14:18:23 -0600
From: Chris Friesen <cfriesen@nortelnetworks.com>
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To: "David S. Miller" <davem@davemloft.net>
CC: hzhong@cisco.com, aebr@win.tue.nl, joris@eljakim.nl,
       alan@lxorguk.ukuu.org.uk, linux-kernel@vger.kernel.org
Subject: Re: UDP recvmsg blocks after select(), 2.6 bug?
References: <003301c4abdc$c043f350$b83147ab@amer.cisco.com>	<41644D86.4010500@nortelnetworks.com> <20041006130615.4f65a920.davem@davemloft.net>
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David S. Miller wrote:
> On Wed, 06 Oct 2004 13:54:46 -0600
> Chris Friesen <cfriesen@nortelnetworks.com> wrote:
> 
> 
>>Would it be so bad to do the checksum before marking the socket readable? 
> 
> 
> Yes, because if we do that we have to make two passes over the
> data instead of one.  It does make a big difference.

Hmm...no easy solution then.

In any case, the current behaviour is not compliant with the POSIX text that 
Andries posted.  Perhaps this should be documented somewhere?

Alternately, how about having the recvmsg() call return a zero, and (if 
appropriate) the length of the name set to zero?  This appears to comply with 
the man page for recvmsg().

Chris
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