Talk:Coding on the xo

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XTEST extension error

I've done the install with yum, (so fantastic that I can yum from the xo!) but in terminal if I try

 $ synergyc -n xo -f 192.168.2.12

I get "XTEST extension not available", and "cannot open secondary screen: unable to open screen"

is there a better way (or place) to start the client?

I'm having the same problem. When I run "synergyc" on the XO, I get the error:
DEBUG: CXWindowsScreen.cpp,840: XOpenDisplay(":0")
ERROR: CXWindowsScreen.cpp,851: XTEST extension not available
FATAL: synergyc.cpp,343: cannot open secondary screen: unable to open screen
If anyone knows how to fix, it would be greatly appreciated (and should perhaps be mentioned in the article).


I discovered how to fix this. The problem is that the XTEST extension is disabled by default on the OLPC (as a security precaution, since it can be used to hijack the mouse/keyboard). Enabling XTEST is quite easy. Edit the "xorg.conf" file:
su
nano /etc/X11/xorg.conf
Find the section marked "Extensions". You'll notice a line that says
Option "XTEST" "Disable"
Just comment-out the line by placing a # at the begging, so that the section looks like:
Section "Extensions"
#Option "XTEST" "Disable" # Mostly a debugging tool
#Option "SECURITY" "Disable" # CRASH!
Option "XC-APPGROUP" "Disable"
Option "XINERAMA" "Disable"
EndSection
Save the file (Ctrl+O), exit the text editor (Ctrl+X) and on the next reboot, XTEST should be loaded and synergy should work.

Another reason that can cause "cannot open secondary screen: unable to open screen" (but without the "XTEST extension not available") is that the synergyc is not able to authentize to X server because it is run from ssh client (and not from desktop) so that $XAUTHORITY is not defined in the shell an synergyc's xlib is not able to locate .Xauthority file (/tmp/.gdmBRAKUA on my system).