Date: Mon, 4 Aug 2003 18:58:19 -0400
To: Stephan von Krawczynski <skraw@ithnet.com>
Cc: Anton Altaparmakov <aia21@cam.ac.uk>, aebr@win.tue.nl,
       linux-kernel@vger.kernel.org
Subject: Re: FS: hardlinks on directories
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	Anton Altaparmakov <aia21@cam.ac.uk>, aebr@win.tue.nl,
	linux-kernel@vger.kernel.org
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From: Andrew Pimlott <andrew@pimlott.net>
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On Mon, Aug 04, 2003 at 04:50:02PM +0200, Stephan von Krawczynski wrote:
> There is a flaw in this argument. If I am told that mount --bind
> does just about what I want to have as a feature then these
> applictions must have the same problems already (if I mount
> braindead). So an implementation in fs cannot do any _additional_
> damage to these applications, or not?

There is a flaw in this flaw.  :-)

/tmp# mkdir a
/tmp# mkdir a/b
/tmp# mkdir a/c
/tmp# mount --bind a a/b
/tmp# ls a  
b  c
/tmp# ls a/b
b  c
/tmp# ls a/b/b/
/tmp#

It is enlightening in this regard to consider the difference between
using unix /etc/fstab and Hurd translators to manage your namespace.

In preparing this example, I discovered that find and ls -R already
have hard-link cycle "protection" built in, so they are broken in
the presence of bind mounts.  :-(

Andrew
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