home/bin/monitor-brightness

   1 #! /bin/bash
   2
   3 _get() {
   4     sudo ddcutil getvcp 10 | grep -o ' current value = \+[0-9]\+' | awk '{print $4}'
   5 }
   6
   7 _set() {
   8     sudo ddcutil setvcp 10 "$1"
   9 }
  10
  11 args="$*"
  12
  13 case "$args" in
  14     '') _get;;
  15     *)
  16         if [[ "$args" =~ ^[0-9]+$ && "$args" -gt -1 && "$args" -lt 101 ]]; then
  17             _set "$args"
  18         else
  19             printf 'Error: expected a numeric argument between 0 and 100, but given "%s"\n' "$args" >&2
  20             exit 1
  21         fi
  22 esac