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Date: Sun, 8 May 2005 14:18:47 -0500
From: Dan Nelson <dnelson@allantgroup.com>
To: ChenMing <chenm@huawei.com>
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cc: freebsd-hackers@freebsd.org
Subject: Re: doubt: msgrcv not return EAGAIN?
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In the last episode (May 07), ChenMing said:
> I use following line to recive message from message queue:
> 
> int ret;
> ret = msgrcv(msgid, &msg, sizeof(msg), 0, IPC_NOWAIT) if (ret == -1) {
>     if (errno == EAGAIN){
>         // no message in queue
>     }
>     else{
>         // here is an error occur
>     }
> }
> 
> but it sounds not works as my expected. It never return errno=EAGAIN,
> however it return errno=ENOMSG instead, but msgrcv manual say its
> should return EAGAIN. what's wrong?

I think the manpage is incorrect.

-- 
	Dan Nelson
	dnelson@allantgroup.com