Arch Dual Monitor configuration

03-07-21 8:31 simon

I have two monitors and only ever use one at a time, I have a script and keyboard shortcut to switch between them but at the moment 99% of my time is at one monitor.

When I login I have script switch the other monitor off but after putting the machine to sleep they both wake up. I can manually run the script to turn the unneeded one off but because I cannot see it I often forget.

So here is my solution.

I created a file 

/usr/lib/systemd/system-sleep/monitor.sh

and in it has 

#!/bin/sh
case $1/$2 in
  pre/*)
    ;;
  post/*)
    sleep 5
    export DISPLAY=:0
    sudo -u simon xrandr --output HDMI-0 --off > /tmp/randr.dbg 2>&1
    ;;
esac

The script must be executable so 

sudo chmod +x /usr/lib/systemd/system-sleep/monitor.sh
The sleep part is needed to wait until both displays are awake, otherwise the command fails.

The sudo to my user is the extra piece that took some finding, a special thanks to this thread for pointing out a solution.

If you need a different option you can use any xrandr command and it will work.