Comment 57 for bug 199960

@seb128, part of a patch that I sent you earlier included a test for Xgl which I knew would break in this case - you rejected the patch because part of it was parsing Xorg.0.log. However the portion that tests for Xgl is independent and seems still valid. While I agree that xgl is not supported and should be discouraged, it seems like it would risk little to just include a check for it, and terminate xrandr stuff gracefully if they had it installed.

Attached is a short example program to demo the code that would be employed. If you are willing to accept a patch, I can prepare one using this test for gnome-settings-daemon and gnome-control-center. It will also require adding a build-dep against libxv-dev.

Fwiw, I have seen numerous other reports in the past of people who had inadvertently installed xserver-xgl back in Feisty days, which sometimes caused massive performance issues after upgrading to Gutsy. I'm not sure exactly what caused so many people to get xgl turned on, though.

@XGL users - if someone could compile and run this program and check that it does indeed detect Xgl, it would be appreciated.