PAM, X11, and su as a normal user?

[Steven G. Kargl]

Matthew Seaman wrote:
> On Fri, Sep 05, 2003 at 12:18:40PM -0700, Steven G. Kargl wrote:
> > After a few hours of frustation, it's time to ask a question.
> > 
> > I have 2 accounts on my machine.  I use startx to start
> > X11 as user kargl.  If I then su to user sgk, I cannot
> > fire up X clients.  For example,
> > 
> > troutmask:kargl[202] su sgk
> > Password:
> > troutmask:sgk[201] gnuplot
> > Terminal type set to 'x11'
> > gnuplot> plot sin(x)
> > gnuplot> 
> > gnuplot: unable to open display 'troutmask.apl.washington.edu:0'
> > gnuplot: X11 aborted.
> > 
> > I've tried using "xhost sgk@", but this doesn't work.
> > The only thing I can think of that may need to be
> > configured is PAM, but the documentation is rather
> > incomplete.  So, anyone know how to setup su to
> > permit sgk to use X clients?
> 
> As user kargl:
> 
>     % xauth nextract /tmp/foo ${DISPLAY}
> 
> As user sgk:
> 
>     % xauth nmerge /tmp/foo
> 
> and remember to delete /tmp/foo as soon as possible.
> 

I still get the above results with gnuplot after issuing the
two xauth commands you give above.  If I use "xauth list"
with as both users the entry for $DISPLAY shows the same key. 

troutmask:sgk[246] xauth list
troutmask.apl.washington.edu:0  MIT-MAGIC-COOKIE-1  some_long_string
troutmask:kargl[245] xauth list
troutmask.apl.washington.edu:0  MIT-MAGIC-COOKIE-1  some_long_string


I suspect that I need to add something to /etc/pam.d/{su,system,xserver},
but I can't locate adequate documentation.

-- 
Steve
http://troutmask.apl.washington.edu/~kargl/