Using X Windows remotely from cygwin

[Douglas Denholm]

I have my YDL box in the basement networked with the rest of my machines
through a router.

I am wanting to connect to it using two other machines I have in the rest of
the house.

One is a titanium G4 and I am able to connect to the YDL box from it using
both straight ssh and X11 over ssh without problem.

I also want to use cygwin on my WinXP box to to connect to the YDL box.

I can make a basic commandline ssh connection from cygwin to the YDL box but
when I try and set up an X Windows session, it dies.

I am using the command "ssh -Y -l root YellowDog" under cygwin (the syntax
suggested in the cygwin user guide). This prompts me for the root password
on the YDL box and then initiates a commandline on the YDL. But when I try
to use X (for example by typing "startkde") I get the following behavior:

[root@YellowDog/]# startkde
rm:cannot remove '.' or '..'
rm:cannot remove '.' or '..'
xsetroot: unable to open display ''
xrdb: Can't open display ''
xset: unable to open display ''
xset: unable to open display ''
xset: unable to open display ''
startkde: Starting up...
ksplash: cannot connect to X server
kdeinit: aborting. $Display is not set.
Warning: connect() failed: No such file or directory
ksmserver: cannot connect to X server
startkde: shutting down...
Warning: connect() failed: No such file or directory
Error: Can't contact kdeinit
startkde: Running shutdown scripts...
startkde: Done
[root@YellowDog /]#

Now I sort of get the idea that $Display needs to set so that the X Window
appears on my local machine (the WinXP box) rather than on the YDL monitor.
But I don't know where (or how) I set it. And I thought that by initiating
the X connection by using ssh -Y from my WinXP box, that the $Display
variable would be automatically set.

When I create the session from X11 on my OSX box, I startup an X11 window
and then use 'ssh YellowDog -X -l root' and everything works automatically
without my setting the $Display variable. And yes, I realize that the ssh
syntax I used with OSX X11 is different from what I used with cygwin... The
cygwin syntax was taken directly from the cygwin user guide... Besides, I
tried using the same ssh syntax I use successfully with OSX X11 but it
doesn't work on cygwin either.

Any suggestions would be welcome ;)

TIA,

--Doug