Reply-To: <hzhong@cisco.com>
From: "Hua Zhong" <hzhong@cisco.com>
To: "'Chris Friesen'" <cfriesen@nortelnetworks.com>,
       "'Jean-Sebastien Trottier'" <jst1@email.com>
Cc: "'Linux Kernel'" <linux-kernel@vger.kernel.org>,
       "'Alan Cox'" <alan@lxorguk.ukuu.org.uk>,
       "'David S. Miller'" <davem@redhat.com>
Subject: RE: UDP recvmsg blocks after select(), 2.6 bug?
Date: Thu, 7 Oct 2004 11:20:32 -0700
Organization: Cisco Systems
Message-ID: <00e501c4ac9a$556797d0$b83147ab@amer.cisco.com>
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> This actually sounds quite interesting.
> 
> For applications that are prepared to handle the nonblocking 
> case, you get full speed.  For applications coded to POSIX, 
> you get correctness.
> 
> It does mean that select() is now a bit more complicated, but 
> applications become much easier to write.

It was my original proposal. The only question is to return which error
code. We cannot return EAGAIN as Posix explicitly disallows it. Is EIO good?
Or some other new error code?

As far as implmentation goes, we probably need a "check_data" function in
the f_ops. Default it could be NULL.

The question is that is it worth the trouble to be Posix complaint? Seems
most developers think not, especially since it has been this way for so long
a time.

Hua

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