From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934412AbXGLUlv (ORCPT ); Thu, 12 Jul 2007 16:41:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756440AbXGLUkW (ORCPT ); Thu, 12 Jul 2007 16:40:22 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:36671 "EHLO amd.ucw.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S934063AbXGLUkV (ORCPT ); Thu, 12 Jul 2007 16:40:21 -0400 Date: Thu, 12 Jul 2007 10:48:46 +0200 From: Pavel Machek To: Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org, Kay Sievers Subject: Re: [PATCH 01/61] Rules on how to use sysfs in userspace programs Message-ID: <20070712084846.GA1882@elf.ucw.cz> References: <20070711233021.GA5253@kroah.com> <11841967403365-git-send-email-gregkh@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <11841967403365-git-send-email-gregkh@suse.de> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.11+cvs20060126 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed 2007-07-11 16:31:20, Greg Kroah-Hartman wrote: > From: Kay Sievers > > Here's a document to help clear things up. > > Signed-off-by: Kay Sievers > Signed-off-by: Greg Kroah-Hartman > --- > Documentation/sysfs-rules.txt | 166 +++++++++++++++++++++++++++++++++++++++++ > 1 files changed, 166 insertions(+), 0 deletions(-) > create mode 100644 Documentation/sysfs-rules.txt > > diff --git a/Documentation/sysfs-rules.txt b/Documentation/sysfs-rules.txt > new file mode 100644 > index 0000000..42861bb > --- /dev/null > +++ b/Documentation/sysfs-rules.txt > @@ -0,0 +1,166 @@ > +Rules on how to access information in the Linux kernel sysfs > + > +The kernel exported sysfs exports internal kernel implementation-details > +and depends on internal kernel structures and layout. It is agreed upon > +by the kernel developers that the Linux kernel does not provide a stable > +internal API. As sysfs is a direct export of kernel internal > +structures, the sysfs interface can not provide a stable interface eighter, > +it may always change along with internal kernel changes. It is also agreed upon by the kernel developers that the Linux kernel does have a stable user<->kernel API... so we have a small problem here. Maybe solution is to declare /sys unstable, but... perhaps /sys can stop mirroring internal structures? I do not think we should codify our failure to keep /sys stable here. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html