Intel Screen Backlight control

intel-backlight-control.sh

#!/bin/bash
# intel-backlight-control.sh [brightness-in/-decrease value]
# intel-backlight-control.sh +400
# intel-backlight-control.sh -400

folder="/sys/class/backlight/intel_backlight"

# the values can be read "/sys/class/backlight/intel_backlight/max_brightness"
max=24242
min=1000

currentValue=$(cat $folder/brightness)
addValue=$1
setValue=$(($currentValue + $addValue))

echo $setValue

if [ $setValue -lt 100 ]; then
 setValue=100;
elif [ $setValue -gt $max ]; then
  setValue=$max;
fi

echo $folder/brightness
echo -n $setValue > $folder/brightness