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Date: Thu, 28 Feb 2019 21:12:58 -0800
From: Samuel Thibault <samuel.thibault@gnu.org>
Message-ID: <20190301051258.ylba7d4zg5uobk3i@function>
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Subject: Re: [Qemu-devel] [PATCH] socket: fix blocking udp recvfrom.
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To: llyzs <llyzs.vic@gmail.com>
Cc: qemu-devel@nongnu.org, Jan Kiszka <jan.kiszka@siemens.com>, =?utf-8?Q?Marc-Andr=C3=A9?= Lureau <marcandre.lureau@gmail.com>

llyzs, le ven. 01 mars 2019 12:27:31 +0800, a ecrit:
> I believe this is because UDP packet can have 0 length payload.

Ah, right, that one makes sense indeed.

> I also found out that sometimes ioctlsocket() call can return error
> (probably caused by my unstable wifi linux driver), in which case we
> can also return immediately.

We should check for the value returned by ioctlsocket() then, otherwise
the value of n is undefined.

Samuel