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From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: "Ricardo J. Rodríguez" <ricardo.rdez@gmail.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Semaphores with timeouts
Date: Thu, 14 Feb 2008 00:14:54 +0000	[thread overview]
Message-ID: <20080214001454.4e8cb0eb@core> (raw)
In-Reply-To: <9a8e2be0802131608m7eef61efmaee332a661503f39@mail.gmail.com>

On Thu, 14 Feb 2008 01:08:28 +0100
"Ricardo J. Rodríguez" <ricardo.rdez@gmail.com> wrote:

> Hi everybody,
> I'm developing a driver to support a new protocol on the kernel 2.6.x,
> a real time communication protocol used in robotic fields. Skipping
> the intro: I need to know if there is any function in the kernel to
> get the process sleeping, as down_interruptible(...), but with
> timeouts, I mean, I want the process to wake up if no signal is
> detected in a while...

The Unix world normally expects rather different behaviour

With O_NDELAY set -> no delay but -EAGAIN
Normal -> delay until error or completes or EOF

and the use of poll/select to wait until the event can be issued and is
going to complete. Hence the lack of a mutex_lock_interruptible_timeout()


It's certainly possible to add one but the first question would be "why
do you need it - what sort of API are you trying to build"

Alan

  reply	other threads:[~2008-02-14  0:26 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-02-14  0:08 Semaphores with timeouts Ricardo J. Rodríguez
2008-02-14  0:14 ` Alan Cox [this message]
2008-02-14 13:34   ` Ricardo J. Rodríguez

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