bash script to toggle a secondary monitor on or off

dualhead.sh

#! /bin/bash

# DUALHEAD.SH - automatic script that toggles the secondary screen on and off
# 				requires xrandr and optionally feh to set the background image
#				for the desktop(s).

###		LVDS1 is the main screen on my laptop
###		HDMI1 is the secondary screen attached via hdmi and is hanging on the wall
###		above the laptop

# if the file doesn't exists we can assume the secondary screen is off
if [[ ! -r /tmp/dualhead ]]; then
	echo 0 > /tmp/dualhead
fi

readstatus () {
	if [[ $(cat /tmp/dualhead) -eq 0 ]]; then
		startstop start
	else
		startstop stop
	fi
}

startstop () {
case $1 in
  start ) xrandr --output LVDS1 --mode 1366x768 --output HDMI1 --mode 1360x768 --above LVDS1
          source ~/.fehbg
          echo 1 > /tmp/dualhead
        ;;
  stop  ) xrandr --output HDMI1 --off
		  echo 0 > /tmp/dualhead
        ;;
esac
}

readstatus
exit 0