using a second computer as a mere screen/monitor in X (VNC?)

Question

My goal is to use three monitors with my Linux system. It is a laptop, so adding another video card is not the easiest solution. (I have investigated a number of such options: getting a docking station with a PCI slot, USB/Cardbus vga adapters, etc, and for the time being don't want to go that way.)

I am wondering if using an older desktop+screen I have lying around as the third "monitor" might be the easiest solution, if only there is a way to get it to work as a seamless, integrated desktop.

I was wondering if I can use VNC or perhaps X itself (?) to achieve the following:

• computer A is my main computer; it has all my files, etc.
• computer B is used just to display on an additional screen
• keyboard+mouse are connected to computer A
• use VNC or X to connect the two so that computer B shows a X screen that is just as if it was a third physical screen connected to computer A.

I don't know if the last point is clear, but what I mean is that I would like to be able to:

• be able to have my window manager assign/move around virtual desktops on all three screens
• move windows back and forth between the screens attached to computer A and the screen of computer B
• be able to copy something in an app being shown on a screen of computer A and paste it into an app being shown on the screen attached to computer B
• access the filesystem on my main computer (A) when using applications that are being shown on the screen attached to computer B

Basically, I would like X to treat computer B just like it was nothing but a third physical screen...

Is this doable? : )

~lara

Solution 1

That's what DMX: Distributed Multi-head X is designed to do, unfortunately it's been broken in several X.Org releases, so you may have to work a bit to get it working.

Solution 2

Looking for an answer for myself (using an iPad instead of a computer), I found the best option to be using VNC, specifically tightvnc. See here: https://help.ubuntu.com/community/VNC/Servers#tightvncserver

Comments

[foraidt]

If you want to avoid buying extra hardware due to the costs, you should also take the power consumption of computer B into account. If B is quite power hungry, special hardware may be an economically better solution.