Date: Sun, 6 Jul 2008 19:22:33 +0300
From: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
       Marcin Slusarz <marcin.slusarz@gmail.com>,
       LKML <linux-kernel@vger.kernel.org>, Frans Pop <elendil@planet.nl>
Subject: Re: [PATCH] parport/ppdev: fix registration of sysctl entries
Message-ID: <20080706192233.5df9c65b@linux360.ro>
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On Sun, 6 Jul 2008 09:11:26 +0100
Al Viro <viro@ZenIV.linux.org.uk> wrote:

> On Sat, Jul 05, 2008 at 11:49:26PM -0700, Eric W. Biederman wrote:
> > So our choices appear to be.
> > - Change the name in sysctl so each parport device always has a
> > unique name.
> > - Only allow one opener of ppdev for a given port.
> 
> Can't do - it's a legitimate use of ppdev (several userland programs
> multiplexing the sucker).

How in the world would such a thing work?! I imagine one could
read()/write() there and multiplex data, but isn't the whole point of
ppdev to allow non-standard communication (manually flipping control
and data lines)? I've used it for custom hardware.

IMHO, there is one reason ppdev exists: allow both _safe_ and _raw_
access to the parallel port, and a much better alternative to the iopl
stuff.


	Eduard
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