ubuntu change lid action: ignore, suspend, hibernate

change_lid_action.sh

#!/bin/bash
if [[ $EUID -ne 0 ]]; then
   echo "This script must be run as root" 
   exit 1
fi

replace_var_in_file() {
  VAR=$1
  VALUE=$2
  FILENAME=$3
  grep -q "^$VAR=" ${FILENAME} && sed -i 's/^$VAR=.*$/$VAR=$VALUE/' $FILENAME || echo "$VAR=$1" >> $FILENAME
}

PARAM=$1

case $PARAM in
  ignore | suspend | hibernate )
    echo "changing lid to $PARAM"
    ;;
  *)
    echo $"Usage: $0 {ignore|suspend|hibernate}"
    exit 1
esac

replace_var_in_file "HandleLidSwitch" $PARAM "/etc/systemd/logind.conf"
service systemd-logind restart
echo "Done."