From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Jeffray <ian@jeffray.co.uk>
Subject: Re: sendfile() behavior while troubleshooting netdevice
Date: Tue, 29 Jul 2008 01:27:09 +0100
Message-ID: <488E63DD.4020406@jeffray.co.uk>
References: <20080728190707.329d247b@osprey.hogchain.net>
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Cc: netdev@vger.kernel.org
To: Jay Cliburn <jacliburn@bellsouth.net>
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Jay Cliburn wrote:
> I'm troubleshooting the problem reported here and I need some help:  
> http://lkml.org/lkml/2008/7/15/325.  

[snip]

> The last round came up short 8 bytes.  Any idea why?  Client and server
> source code attached.
> 
> It doesn't matter which host is the server or client; data is lost
> either way.

Because you send() a strlen() amount of data for the filesize,
but recv() a sizeof(cfsize) amount of data?   I supect 8 bytes
is being sucked up in your first recv().  Try sending a fixed
size block for the file size.

Ian.