Hi there. Wasn't 100% sure where the proper place would be to post this. Seems to me like a beginners question, mostly because I'm not entirely sure of the terminology used. A disclaimer right at the top(ish) since as I wrote this out I realized this may grab someone's attention... yes I'm using root, and yes the end-user is using root; I understand the risks.

I have a Ubuntu server (12.04 LTS) running at a remote site, connected by WAN. I started with SSH access, and as the needs evolved, I ended up needing a graphical display. So I installed ubuntu-desktop, xrdp, x window manager, and gnome-session-fallback (as a suggested fix for a problem I was having getting xrdp working correctly).

I'm able to connect now and connect via Microsoft RDP from a windows station to the Ubuntu server. There may be instances where the end-user at that site using this server will need to run applications locally on this server. This end-user however is not a linux user, and so -finding- the program that they need to run may sometimes be an issue.

I was hoping there was a way for me to SSH into the server, and run a program, pointing it to the Xvnc session open so that the end user logged in via RDP would have it just show up on their screen:
root@sanitized:/# ps aux | grep Xv
root 16331 0.0 0.9 25684 19856 ? S 08:31 0:10 Xvnc :10 -geometry 1680x1050 -depth 16 -rfbauth /root/.vnc/sesman_root_passwd -bs -ac -nolisten tcp


A google search mentioned changing the display variable, and had several commands, but I was hoping I could build an understanding rather than just copy and paste into SSH.

I may be completely off-the-ball on this one, but I do see /proc/10 exists... but I'm not sure where to go from there.

I also saw using ssh -X or ssh -Y, but I'm not sure if that works with an xrdp session?

EDIT:
I see that /proc refers to the PID of a process now. In my case, that would mean I would want /proc/16331 right?

User ended up being done with it sooner than anticipated, gave me some time to test things out.

It seems this works... though if someone more familiar with the topic could enlighten me as to the risks of running xhost + (I've read a comment that it is bad form?) to disable the X11 Forwarding ACLs I'd appreciate it.

The entire process, from my SSH session, was this:

using
ps aux | grep Xv

I was able to get the output as described in my OP. The :10 was the display variable.

I ran xhosts +, and then export DISPLAY=127.0.0.1:10.0 to set the display variable to the Xvnc session. I also confirmed that X11Forwarding was set to yes and X11DisplayOffset was set to 10 within /etc/ssh/sshd_config

I am now able to do something like /usr/bin/firefox and have it launch on the RDP/Xvnc/pickyourname session.