From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Stewart Subject: Re: silent semantic changes with reiser4 Date: Mon, 30 Aug 2004 10:43:58 PDT Message-ID: <1093887838l.11947l.1l@orlando> References: <412F7D63.4000109@namesys.com> <20040827230857.69340aec.pj@sgi.com> Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com In-Reply-To: <20040827230857.69340aec.pj@sgi.com> (from pj@sgi.com on Fri, Aug 27, 2004 at 23:08:57 -0700) Content-Disposition: inline List-Id: Content-Type: text/plain; charset="us-ascii"; delsp="Yes"; format="Flowed" To: Paul Jackson Cc: Hans Reiser , riel@redhat.com, ninja@slaphack.com, torvalds@osdl.org, diegocg@teleline.es, jamie@shareable.org, christophe@saout.de, vda@port.imtp.ilyichevsk.odessa.ua, christer@weinigel.se, spam@tnonline.net, akpm@osdl.org, wichert@wiggy.net, jra@samba.org, hch@lst.de, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, flx@namesys.com, reiserfs-list@namesys.com On 2004.08.27 23:08, Paul Jackson wrote: > Hans wrote: > > We create filename/pseudos/backup, and that tells the archiver what =20 > > to do..... >=20 > Instead of exposing the old semantics under a new interface, why not > expose the new semantics under a new interface. Here's another take on the same theme. To see attrs on files, one can =20 either use a newly developed application which can use special new =20 syscalls/flags on syscalls a Paul Jackson recommends. However from an =20 old shell or application one can also open the attribute node on /home/myself/foo.txt by checking out /attr/home/myself/foo.txt/, which =20 points to the "as directory" node on the filesystem that foo.txt points =20 to. The strange part of this idea is that the /attr filesystem wouldn't be =20 conventionally browsable. An opendir() on any path would return the =20 attributes, not the subdirectory contents, even if the target was a =20 conventional directory. File based operations (open(), unlink(), etc) =20 would operate on the "as directory" node of the dirname() of the file =20 argument. The /attr filesystem would be completely virtual, honoring =20 the permissions, crossing filesystems, and inheriting the root =20 directory of the calling process. Just a thought from a Linux fs layman -- certainly one of the Reiser =20 unwashed masses. -- Paul