From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Lyamin Subject: Re: silent semantic changes with reiser4 Date: Sun, 29 Aug 2004 19:02:31 +0400 Message-ID: <20040829150231.GE9471@alias> References: <412F7D63.4000109@namesys.com> <20040827230857.69340aec.pj@sgi.com> Reply-To: flx@msu.ru Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii 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 Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com To: Paul Jackson Content-Disposition: inline In-Reply-To: <20040827230857.69340aec.pj@sgi.com> List-Id: linux-fsdevel.vger.kernel.org Fri, Aug 27, 2004 at 11:08:57PM -0700, Paul Jackson wrote: > Hans wrote: > > We create filename/pseudos/backup, and that tells the archiver what to > > do..... > > Instead of exposing the old semantics under a new interface, why not > expose the new semantics under a new interface. yeah. that could work. > There exist plenty of programs that know the old Unix semantics. There > don't exist many working programs that use the new semantics that you're > adding. > > I raise again the example of how Windows adapted to long filenames. Old > DOS and FAT programs, including my Unix backups of today, see a 8.3 name > space. Only code that knows the new magic sees the long names. > > If given the choice of breaking much old, existing stuff, or some new, > mostly not yet existing stuff, does not it make more sense to break what > mostly doesn't exist yet? > > One possible way to do this, of no doubt many: > > * Stealing a corner of the existing filename space for > some magic names with the new semantics. > > * A new option on open(2), hence opendir(3), that lights up > these magic names. > > * Doing any of the classic pathname calls with such a > new magic name exposes the new semantics - such calls > as: > access execve mkdir mknod mount readlink > rename rmdir stat truncate unlink > > This means essentially constructing a map between old and new, > such that changes made in either view are sane and visible > from the other view. It would be intresting to hear comments from Hans Reiser on proposals stated above... -- "the liberation loophole will make it clear.." lex lyamin