user@host:~$ xgamma
-> Red 1.000, Green 1.000, Blue 1.000
user@host:~$ xgamma --help
usage: xgamma [-options]
where the available options are:
-display host:dpy or -d
-quiet or -q
-screen or -s
-gamma f.f Gamma Value
-rgamma f.f Red Gamma Value
-ggamma f.f Green Gamma Value
-bgamma f.f Blue Gamma Value
If no gamma is specified, returns the current setting
user@host:~$ xgamma -gamma 0.6
-> Red 1.000, Green 1.000, Blue 1.000
<- Red 0.600, Green 0.600, Blue 0.600