RPI Touchscreen Control

#!/bin/bash
export DISPLAY=:0

while getopts ":ofb:" opt; do
    case $opt in
        o) # on
        sudo sh -c "echo 0 > /sys/class/backlight/rpi_backlight/bl_power"
        ;;
        f) # off
        sudo sh -c "echo 1 > /sys/class/backlight/rpi_backlight/bl_power"
        ;;
        b) # brightness
        sudo sh -c "echo $2 > /sys/class/backlight/rpi_backlight/brightness"
        ;;
    esac
done