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Date: Fri, 23 Apr 2010 21:53:34 -0400
From: tytso@mit.edu
To: Pavel Machek <pavel@ucw.cz>
Cc: Arve Hj??nnev??g <arve@android.com>, linux-pm@lists.linux-foundation.org,
       linux-kernel@vger.kernel.org, Len Brown <len.brown@intel.com>,
       "Rafael J. Wysocki" <rjw@sisk.pl>, Randy Dunlap <rdunlap@xenotime.net>,
       Jesse Barnes <jbarnes@virtuousgeek.org>, Magnus Damm <damm@igel.co.jp>,
       Nigel Cunningham <nigel@tuxonice.net>,
       Cornelia Huck <cornelia.huck@de.ibm.com>, linux-doc@vger.kernel.org
Subject: Re: [PATCH 2/9] PM: suspend_block: Add driver to access suspend
 blockers from user-space
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On Fri, Apr 23, 2010 at 10:43:49AM +0200, Pavel Machek wrote:
> > +To create a suspend_blocker from user-space, open the suspend_blocker device:
> > +    fd = open("/dev/suspend_blocker", O_RDWR | O_CLOEXEC);
> > +then call:
> > +    ioctl(fd, SUSPEND_BLOCKER_IOCTL_INIT(strlen(name)), name);
> 
> 
> This seems like very wrong idea -- it uses different ioctl number for
> each length AFAICT.

Yep, and there's nothing wrong with that IMHO.  It's a clever use of
the _IOC encoding scheme.

						- Ted