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Date: Tue, 24 Feb 2004 11:44:38 -0500 (EST)
From: "Richard B. Johnson" <root@chaos.analogic.com>
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To: Tomas Szepe <szepe@pinerecords.com>
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Subject: Re: can i modify ls
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On Tue, 24 Feb 2004, Tomas Szepe wrote:

> On Feb-24 2004, Tue, 15:55 +0000
> Alessandro Salvatori <a.salvatori@universitari.crocetta.org> wrote:
>
> > it's quite interesting...
>
> Actually, it's not.
>
> 1) The presence/absence of the read permission on a directory determines
> 	whether the user will be able to list the directory's contents.
>
> 2) The fs permission model is enforced by the kernel.  Trying to impose
> 	additional restrictions in userspace is fragile, futile and
> 	an incredibly stupid idea.

If you don't have any programming tools and no access to any (like
a banking or restrictive office environment), and there is no
way to get any external executable files to run, i.e., no floppy
or no shell that could possibly access one, then writing a minimal
'ls' program that allows the clerk to see what's in her directory
might be useful.

So, it just might not be, as you say; "an incredibly stupid idea".

Cheers,
Dick Johnson
Penguin : Linux version 2.4.24 on an i686 machine (797.90 BogoMips).
            Note 96.31% of all statistics are fiction.