run a script at the end of a user session

[Andrew Sullivan <ajs keynes cis mcmaster ca>]

Hi,

I asked about this on IRC today, and got a correct answer to the
question I actually asked.  I wasn't clear enough, though, so I'll
try again.

What I want to be able to do is execute a script as the user when
that user's session ends.  This is analogous to the .logout file in
bash or the ExitFunction-type commands in many window managers.

I have a user who wants to move her .forward file out of the way when
she logs in, and move it back into place when she logs out.  Because
she's not getting a login shell, the .logout file doesn't get read at
exit.

I figure there's got to be a way, since gnome sessions are managed. 
The system in question is using gdm, but I don't see any way to make
user-specific changes using it (since the PostSession stuff would run
anything as root, I think it's too dangerous to use).  I figured that
the logout confirmation is the trick, but I can't tell how I can
configure that or whether it has any hooks to allow me to run another
script.

Any help much appreciated.
-- 
Andrew Sullivan                       |     McMaster University
Research Computing Support, CIS       |   1280 Main Street West
ajs keynes cis mcmaster ca            |       Hamilton, Ontario
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