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Date: Mon, 22 Mar 2010 08:45:36 -0400
From: Eliot Moss <moss AT cs DOT umass DOT edu>
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To: cygwin AT cygwin DOT com
Subject: Re: recvfrom + MSG_PEEK = broken?
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On 3/22/2010 7:03 AM, Corinna Vinschen wrote:
> On Mar 22 02:04, Charles Wilson wrote:
>> I've been tracking down a problem in xinetd. It appears to be an issue
>> with using MSG_PEEK in recvfrom() on UDP sockets.
>
> Yes, that's a bug in Cygwin.  The socket event handling got messed up
> when MSG_PEEK was used.  I fixed that in CVS so it will be in 1.7.2.
> The last time I had problems with MSG_PEEK was back in 2006.  Curious
> how seldomly it's used, apparently.
>
> Thanks for the simple testcase!  It was very helpful to track down
> the problem easily.

I wonder if rsync uses MSG_PEEK? If it does, could this explain the
rsync spinning problem that gets fixed (for me anyway) by not using
socketpair?

Regards -- Eliot Moss

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