xdriinfo -version (return code: 0)
xdriinfo 1.0.5
xdriinfo --help (return code: 1)
xdriinfo: unrecognized argument '--help'
Usage: xdriinfo [-display <dpy>] [-version] [command]
Commands:
nscreens print the number of screens on display
driver screen print the DRI driver name of screen
options screen|driver print configuration information about screen or driver
If no command is given then the DRI drivers for all screens are listed.