X Forward of an Existing Process

trilarian · #1 11-02-2009, 01:04 PM

Hey guys... I know I've done this before but I haven't had the need in awhile and it escapes me what I did.

Basically, I have a box with a ssh service with X11 Forward on. I can connect, initiate a process on the remote box, and see the program as if on the local one - all good.

What I would like to do, though, is say I fire up a process - lets say a cdburn from a gui and not a cli on the ssh service box. Then I go to a remote box and ssh into the one burning the cd. I'd like to pull what is being displayed on the remote box to the local box so that I can see the progress - without looking at text log files - I want the actual display.

This is just a simple example of more I want to do, so getting the actual display as an interactive display is critical. I seem to remember something about finding the process id and connecting to that, but again its been years and I forget.

The other option would be to forward the entire screen, sort of how windows does remote desktop, but I'd prefer on a process by process basis if possible.

Thanks a bunch~

ehawk · #2 11-03-2009, 12:23 PM

This might be a start, shows you how to import a window manager, albeit starting with the command line. From there, you can run your gui.

http://www.vanemery.com/Linux/XoverSSH/X-over-SSH2.html

See setup #3

trilarian · #3 11-03-2009, 01:55 PM

Thanks for the reply. The problem with what the article suggest is that when I ssh into the remote box, I initiate a new desktop environment. I would like to connect to the one already running on the host machine. Also, upon exit, the processes are killed too.

In this case I'm not trying to run my remote machine on the local machine (even though I do that sometimes - is very nice). I am trying to connect to a process already running on an existing instance of X, to either check on status or make a few adjustments, then allow it to continue running when I close the connection.

So maybe another example would be in order. Say I'm downloading a few fansubs via a torrent program and I want to check the status. I could then maybe queue in a few more to download, cancel, turn back on some torrents to seed that I stopped for awhile, etc.

One solution I know will work is to run a VNC client, block the port at the firewall, and tunnel the VNC port through the SSH port. However, I was hoping there was something in the X forward function of SSH to accomplish this.

techwise · #4 11-03-2009, 06:26 PM

Just an idea. Have you tried starting the gui program in screen locally? It would require you to remember to start any X program you want remotely to be launched under screen but it may work. Then upon reconnection to that screen session you may get the X prog. You still of course have to forward X over ssh.

Ill try it myself.

Mike

techwise · #5 11-03-2009, 06:31 PM

Scratch that. Doesnt work.

Mike

trilarian · #6 11-03-2009, 06:47 PM

Seems there was a program xmove that attempted this by creating a x server proxy where the processes were not tied to any particular x server, so any x server could talk to said process.

However, the maintainer went MIA and the package is no longer in the Debian repo. Also, trying to find any information on this only leads to people's attempts and ultimately failures.

So far it seems there is no way to forward an already running process because it is tied to the host x server and there is no program to move it to the local one. I don't see why this is so hard though... if I can execute a program, and it's output forwarded to the remote x server - why can't the same be done for an existing one (even if to be read only - as in copy the stream from x server local to x server remote). And why does x server by default listen to TCP 6000 for remote sessions, but not allow the forward of an existing session?

Oh well... I really didn't want to go the VNC route, but I guess that is my only option.

retsaw · #7 11-04-2009, 09:31 AM

xmove is still available from the Debian repositories, just not for the latest version. You can try downloading it from the etch repository and if the binary package doesn't work, you can instead compile it from source. However, being such an old program, it doesn't support new features of X. I did actually get it working when I used it, but that was some years ago, so maybe it indeed won't work on modern distributions.

Alternatively you may want to run a FreeNX session which you can move between machines, this should perform better than VNC does.

Another solution for your bittorrent example would be to use a bittorrent client with a web-interface, or one with a curses interface that you could run in "screen".

trilarian · #8 11-04-2009, 11:37 AM

Quote:

Originally Posted by retsaw

xmove is still available from the Debian repositories, just not for the latest version.

Yea, I dug through my old notes - basically text files dumped into a directory to remind me of odd things I do. It seems in the past I did use xmove, but with limited success. This box in particular is my desktop, so runs Sid. There is a major bug documented on the Debian Bug List for that program with the versions of X on Testing and Unstable. With the programmer MIA, the package has been permanently removed unless someone picks the project up. So it seems I am out of luck unless I want to pick the project up myself, which I'll admit, is probably more than I can handle right now with two jobs.

Quote:

Originally Posted by retsaw

Alternatively you may want to run a FreeNX session which you can move between machines, this should perform better than VNC does.

Heh, you read my mind. I did a search for 'linux vnc alternative' and FreeNX popped up along with NoMachine. I'm gonna play around with both and see if either do what I need.

Quote:

Originally Posted by retsaw

Another solution for your bittorrent example would be to use a bittorrent client with a web-interface, or one with a curses interface that you could run in "screen".

That would be great, except I have a laundry list of things I want to do remotely. 99% of them really can be done with just SSH and SCP, but as I'm going to be spending more and more time away from home now I've developed a need to connect to the existing X server to make changes. Finding a text version or output of every program just seems tedious and unnecessary in this day and age. It just seems all the tools are there, just a few interconnecting wires are missing. I guess those couple of wires are significant or there would be a working program already.

I'll check out FreeNX and NoMachine - one of them should get me by.

furrycat · #9 11-07-2009, 02:46 PM

No Machine is a good choice for launching a session which you can connect to from anywhere. I run Pidgin like this and connect to it from home and work.

To solve the immediate problem you need only check out this familiar looking thread: http://justlinux.com/forum/showthread.php?t=152101

trilarian · #10 11-09-2009, 11:38 AM

Quote:

Originally Posted by furrycat

No Machine is a good choice for launching a session which you can connect to from anywhere. I run Pidgin like this and connect to it from home and work.

To solve the immediate problem you need only check out this familiar looking thread: http://justlinux.com/forum/showthread.php?t=152101

HA!! I knew I worked this problem out before...

Thanks for the reminder since I seem to have forgotten where my search button went.

EDIT => Even more amusing is that I asked the same question only 3 days apart from a year ago. I must get extra forgetful in November.