xmove + ssh failure

["Jørn V. Christensen" <spam@mettle.dk>]

Hi

This is a follow-up on a thread from january 2004 - if this mail is not 
recognized as a follow-up - please take a look at the problem on 
http://lists.debian.org/debian-user/2004/01/msg01220.html .

Root of the problem:
--------------------
When you log into a server with SSH (with X11 forwarding), your 
.Xauthority file gets updated with a cookie (generated by SSH? - its not 
the original cookie anyway) belonging to a display named
  <server name>/unix:<display>

e.g.
  jvc@mya:~$ xauth l
  <snip>
  mya/unix:13  MIT-MAGIC-COOKIE-1  27be74025ceb8842d2b7d50aa0a60a68
  <snip>

(yes - you guessed right - my server name is 'mya').

Your DISPLAY variable, on the other hand, belongs to 'localhost':
  jvc@mya:~$ echo $DISPLAY
  localhost:13.0

For most programs this is fine - but for Xmove, it is a problem. So... 
tough luck!


A solution:
-----------
Very simple: Just add a line to your .Xauthority file (use xauth) 
belonging to localhost with the same display and cookie and everything 
works. E.g.:

* Terminal 1:
  jvc@jvc:~$ ssh -X mya
  <snip>
  jvc@mya:~$ xauth add $DISPLAY MIT-MAGIC-COOKIE-1 `xauth l
  "mya/unix${DISPLAY/localhost/}" | cut -f 5 -d ' '`
  jvc@mya:~$ xmove -port 3
  Implementing MIT-MAGIC-COOKIE-1 user authentication
  XMove 2.0 ready.

* Terminal 2:
  jvc@jvc:~$ ssh -X mya
  <snip>
  jvc@mya:~$ xauth add $DISPLAY MIT-MAGIC-COOKIE-1 `xauth l
  "mya/unix${DISPLAY/localhost/}" | cut -f 5 -d ' '`
  jvc@mya:~$ DISPLAY=:3 xterm

and voila... (Here I used display :3 because display :1 was already 
taken by another xmove :P)


A side note:
------------
When moving windows (apps) from one display to another, be sure to 
update your authority credentials first. If you do not, both xmove and 
xmovectrl will crash looping, burning CPU cycles trying to do... well... 
apparently nothing!

Apart from that, I think it is a _great_ app which actually deserved a 
good maintainer to fix little bugs like the one mentioned above and the 
fact that the pixel depth of destination Xserver must be the same as the 
pixel depth of your source Xserver.

Using xmove in combination with screen really gives you a lot of 
opportunities to have a server (without any screens attached - or even 
an Xserver running) running your e.g. icq-client and just have it moved 
to your laptop when working on that, or... well... you get the point, I 
assume...

Have fun
~Jørn

P.S. - sorry to use the mail adress I am using - but I don't want to 
much spam om my primary adress. Want to contact me, replace 'spam' with 
'mail' in my sender adress...