How to Determine if LCD Monitor is Turned on From Linux Command Line

Question

How do you tell if a computer\'s monitor(s) are turned on/off from the command line in Linux? I\'ve traditionally thought of monitors as output-only devices, but I\'ve noticed t

Answer 1

When using xset it always returns xset: unable to open display ""

However, "xset dpms force off" & "xset dpms force off" commands actually turn my monitor off and on. I am using the script outlined here -

http://systembash.com/content/how-to-turn-off-your-monitor-via-command-line-in-ubuntu/