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Date: Tue, 8 Apr 2003 23:49:44 +0400
From: "Andrey A. Chernov" <ache@nagual.pp.ru>
To: Bruce Evans <bde@zeta.org.au>
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cc: arch@freebsd.org
cc: Yar Tikhiy <yar@freebsd.org>
Subject: Re: termios & non-blocking I/O
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On Wed, Apr 09, 2003 at 05:33:28 +1000, Bruce Evans wrote:
> The spec is not very clear, but I think it means to say to return
> -1/EAGAIN (it says that first).

POSIX says:

IEEE Std 1003.1-200x does not specify whether the setting of O_NONBLOCK
takes precedence over MIN or TIME settings. Therefore, if O_NONBLOCK is
set, read( ) may return immediately, regardless of the setting of MIN or
TIME. Also, if no data is available, read( ) may either return 0, or
return -1 with errno set to [EAGAIN].

-- 
Andrey A. Chernov
http://ache.pp.ru/