From: Sytse Wielinga <s.b.wielinga@student.utwente.nl>
To: linux-kernel@vger.kernel.org
Subject: Re: [PATCH for testing] cow behaviour for hard links
Date: Thu, 11 Mar 2004 00:07:43 +0100
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On Wednesday 10 March 2004 20:34, J?rn Engel wrote:
> Interna:
> I introduced a new flag for inodes, switching between normal behaviour
> and cow for hard links.  Flag can be changed and queried per fcntl().
> Ext[23] needed a bit of tweaking to write this flag to disk.  open()
> will fail, when a) cowlink flags is set, b) inode has more than one
> link and c) write access is requested.

I really like this! It makes me wonder why anyone hasn't come up with this 
idea before...

Pitifully, it only solves half of the problem: it does make sure you can't 
make any mistakes anymore, but it doesn't break the files up when a process 
wants to write to a linked file. You still have to copy and move every time 
you wish to edit a file. I'd like to have the kernel doing just that. I'll 
have a look whether I can write a patch, but I don't promise anything as I 
don't have much time :-)

Sytse
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