Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933148AbXFSDRS (ORCPT ); Mon, 18 Jun 2007 23:17:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763135AbXFSDRE (ORCPT ); Mon, 18 Jun 2007 23:17:04 -0400 Received: from smtpout.mac.com ([17.250.248.174]:57439 "EHLO smtpout.mac.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762088AbXFSDRB convert rfc822-to-8bit (ORCPT ); Mon, 18 Jun 2007 23:17:01 -0400 In-Reply-To: <20070618212423.GB19713@cynthia.pants.nu> References: <8wsW4-3UY-3@gated-at.bofh.it> <8wJal-3KA-1@gated-at.bofh.it> <8xm22-4Ql-1@gated-at.bofh.it> <8xq5G-32l-7@gated-at.bofh.it> <8xs7w-69W-21@gated-at.bofh.it> <4676F9A2.6010007@zytor.com> <20070618221021.GB2062@thunk.org> <20070618222656.GB25089@lazybastard.org> <20070618212423.GB19713@cynthia.pants.nu> Mime-Version: 1.0 (Apple Message framework v752.2) Content-Type: text/plain; charset=ISO-8859-1; delsp=yes; format=flowed Message-Id: Cc: =?ISO-8859-1?Q?J=F6rn_Engel?= , Theodore Tso , "H. Peter Anvin" , alan , Bodo Eggert <7eggert@gmx.de>, Jack Stone , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, akpm@linux-foundation.org, viro@zeniv.linux.org.uk Content-Transfer-Encoding: 8BIT From: Kyle Moffett Subject: Re: Versioning file system Date: Mon, 18 Jun 2007 23:15:51 -0400 To: Brad Boyer X-Mailer: Apple Mail (2.752.2) X-Brightmail-Tracker: AAAAAA== X-Brightmail-scanned: yes Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1514 Lines: 31 On Jun 18, 2007, at 17:24:23, Brad Boyer wrote: > On Tue, Jun 19, 2007 at 12:26:57AM +0200, J?rn Engel wrote: >> Pointless here means that _I_ don't see the point. Maybe there >> are valid uses for extended attributes. If there are, noone has >> explained them to me yet. > > The users of extended attributes that I've dealt with are ACL > support and SELinux. These both use extended attributes under the > covers. It's just not immediately obvious if you aren't looking. Yeah, extended attributes are typically used for exactly that: "attributes" like labels, permissions, encoding, cached file-type, DOS/Windows/Mac metadata, etc. Sometimes people suggest sticking icons in there, but that's probably a bad idea. At most stick an "icon label" attribute which refers to a file "/usr/share/icons/ by_attr/$ICON_LABEL.png". If you're trying to put more than 256 bytes of data in an extended attribute then you're probably doing something wrong. They're very good for cached attributes (like file- type) where you don't care if the data is lost by "tar", and they're reasonable for security-related attributes where you don't want attribute-unaware programs trying to save and restore them (like SELinux labels). Cheers, Kyle Moffett - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/