linux-kernel - Re: select() on /dev/input/eventX not level-triggered?

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Message-ID: <20110523212016.GA24969@elf.ucw.cz>
Date:	Mon, 23 May 2011 23:20:16 +0200
From:	Pavel Machek <pavel@....cz>
To:	Dmitry Torokhov <dmitry.torokhov@...il.com>
Cc:	kernel list <linux-kernel@...r.kernel.org>,
	linux-input@...r.kernel.org
Subject: Re: select() on /dev/input/eventX not level-triggered?

On Mon 2011-05-23 13:49:10, Dmitry Torokhov wrote:
> On Mon, May 23, 2011 at 10:06:22PM +0200, Pavel Machek wrote:
> > On Mon 2011-05-23 11:13:12, Dmitry Torokhov wrote:
> > > On Fri, May 20, 2011 at 01:50:51AM +0200, Pavel Machek wrote:
> > Difference was I'm not using non-blocking read().
> 
> Does not matter.
> 
> > It is unusual but
> > should work AFAICT. Just read one packet when select shows its ready;
> > if there's more than one, don't loop around read, but rely on select
> > returning immediately.
> > 
> > I did verify it on strace, so it should not  be python artefact.
> 
> It is artefact of your program, you buffering your input. Use:
> 
> 	file = open("/dev/input/event3", "rb", 0)

Oops, yes, you are right, that solves it. Thanks... and sorry for the
noise.
									Pavel
-- 
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