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I'm planning to use my 7" Android tablet as second screen via VNC.

Sharing my main screen works fine with x11vnc, but that is not what I want.

So I created a second screen using the xorg86-video-dummy driver and share this screen with x11vnc -display :1 which works but I don't get it managed to use xrandr "extending" this screen with the main screen... .

What am I doing wrong or is there a better solution? The driver for the main screen is the cs nvidia one.

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migrated from Jul 3 '11 at 14:22

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Can you try to clear up a few ambiguities for me? Where are you creating this second screen? I don't understand what you mean by "which works but I don't get it ma[n]aged to use xrandr 'extending' this screen with main screen" either. If you could clarify your question, I think you'd have a better chance at getting a good response. –  Jeff Welling Jul 3 '11 at 17:02
> but I don't get it mamaged to use xrandr "extending" this screen What did you try? What happenned when you tried it? What does xrandr --auto show? –  symcbean Jul 4 '11 at 12:35
user@Thinkpad-T61>xrandr --screen 1 xrandr: Failed to get size of gamma for output default Screen 1: minimum 320 x 240, current 1024 x 768, maximum 1024 x 768 default connected 1024x768+0+0 0mm x 0mm 1024x768 60.0* 800x600 60.0 56.0 640x480 60.0 512x384 60.0 400x300 60.0 56.0 320x240 60.0 –  Guido Krömer Jul 4 '11 at 20:39
caco@Thinkpad-T61>xrandr --screen 0 xrandr: Failed to get size of gamma for output default Screen 0: minimum 320 x 175, current 1440 x 900, maximum 1440 x 900 default connected 1440x900+0+0 0mm x 0mm 1440x900 50.0* 51.0 52.0 1024x768 53.0 54.0 55.0 56.0 57.0 ... –  Guido Krömer Jul 4 '11 at 20:40
But i can't set something like "xrandr --output VGA-0 --left-of LVDS" or in my case somethig like this "xrandr --output --Screen-1 --left-of -Screen-0"(If something is possible with Xrandr...) –  Guido Krömer Jul 4 '11 at 20:44

1 Answer 1

I think I have found a solution using xdmx instead of xrandr; I will try this on a virtual machine running two xservers (with dummy devices) plus xdmx as primary xserver.

My first try with two "dummy xservers":

Xorg :2 -config /etc/X11/xorg.conf.dummy & // my "real screen"
Xorg :3 -config /etc/X11/xorg.conf.dummy & // my "vnc screen"
Xdmx :4 +xinerama -display localhost:2 -display localhost:3 &
x11vnc -display :3 -noshm

Works, but now I have to tell slim to work with xserver number 4 and put this all together into a failsafe bash script.

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