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Date: Mon, 13 Aug 2012 09:26:38 +0200
From: Kevin Wolf <kwolf@redhat.com>
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To: Michael Tokarev <mjt@tls.msk.ru>
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Cc: qemu-trivial@nongnu.org, Peter Maydell <peter.maydell@linaro.org>,
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Subject: Re: [Qemu-trivial] [PATCH] iov_send_recv(): Handle zero bytes case
 even if OS does not
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Am 12.08.2012 12:32, schrieb Michael Tokarev:
> On 12.08.2012 01:24, Peter Maydell wrote:
>> POSIX allows sendmsg() and recvmsg() to fail EMSGSIZE if passed a zero
>> msg.msg_iovlen (in particular the MacOS X implementation will do this).
>> Handle the case where iov_send_recv() is passed a zero byte count
>> explicitly, to avoid accidentally depending on the OS to treat zero
>> msg_iovlen as a no-op.
>>
>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>> ---
>> This is what was causing 'make check' to fail on MacOS X.
>> The other option was to declare that a zero bytecount was illegal, I guess.
> 
> Acked-by: Michael Tokarev <mjt@tls.msk.ru>
> 
> Kevin, does this fix the test-iov failure you're seeing on one of
> the build bots?

It's not on a build bot but on my test machine, but yes, this does fix
it indeed. Thanks for looking into it, Peter!

Kevin