From mboxrd@z Thu Jan  1 00:00:00 1970
From: Huajun Li <huajun.li.lee@gmail.com>
Subject: Re: write() udp socket
Date: Sun, 24 Jul 2011 16:33:10 +0800
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To: ZHOU Xiaobo <xb.zhou@qq.com>
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2011/7/23 ZHOU Xiaobo <xb.zhou@qq.com>:
> question No1:
> When I call
> ssize_t write(int fd, const void *buf, size_t count);
>
>
> on a nonblocking UDP socket, is the return value =A0always equal to '=
count'?
>
>

I don't think so.  The function may be interrupt by signal or return
due to other reason, so the return value only represents the size it
writes successfully to the fd.

> question No2:
> Can I write() a UDP socket in multiple threads without locking?
>

In my opinion, you could. However, the receiver may not get what you ex=
pected.
>
> thanks
>
>
> ------------------
> Sincerely yours
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 ZHOU Xiaobo