Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 12 Mar 2002 02:59:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 12 Mar 2002 02:59:05 -0500 Received: from thebsh.namesys.com ([212.16.7.65]:29450 "HELO thebsh.namesys.com") by vger.kernel.org with SMTP id ; Tue, 12 Mar 2002 02:58:47 -0500 Message-ID: <3C8DB535.7080807@namesys.com> Date: Tue, 12 Mar 2002 10:58:45 +0300 From: Hans Reiser User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.6) Gecko/20011120 X-Accept-Language: en-us MIME-Version: 1.0 To: James Antill CC: Larry McVoy , Tom Lord , jaharkes@cs.cmu.edu, linux-kernel@vger.kernel.org Subject: Re: linux-2.5.4-pre1 - bitkeeper testing In-Reply-To: <3C8C4B8A.2070508@namesys.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Clearcase handles all of this in the filesystem, and it all works pretty much reasonably. Lots of details, but let's worry about them after we have a patch, shall we?.... Hans James Antill wrote: >Hans Reiser writes: > >>Alexander Viro wrote: >> >>>On Mon, 11 Mar 2002, Hans Reiser wrote: >>> >>>>So the problem was that it was not optional? >>>> >>>The problem is that it doesn't play well with other things. >>> >>Your statement is information free so far, but could be the intro to >>an informative statement....;-) >> > > Think about what people want to do with SCM, think about how the >filesystem can help. > Just having a special flag to open() that enables versioning on close() >is useless to 99% of people IMO. > > For something like that to be worth it it'd need to support rename(), >symlink(), link(), unlink() and _importantly_ chmod()/chown() (you >don't want previous versions of a file becoming readable just because >you chmod() the final version). > > Off the top of my head the places where I might find a use for it... > >1. tar -x ... hack ... tell fs to generate diff > (can be done via. cp -al now, but possibly easier with fs support) > >2. Version control my mail box (the good readers have the mark deleted >and then purge, which removes some of the need). Version control >might be clumsy (say you delete 3 mails, and want only one back), and >doesn't work with a mailer that does any caching on the mailbox. > >3. Putting an entire website under it. > >...and all but 3. are probably better done a different way (a shared >library might be nice ... and would also be fs/kernel independent) and >I'd imagine it's overkill for 3. as the biggest problem is saving over >the wrong filename so undelete is enough. > - 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/