Adjust brightness on active display

Bin/brightness.sh

@@ -1,6 +1,7 @@
 #! /bin/bash
 
 CURRENT=`xrandr --verbose | grep -m 1 -i brightness | cut -f2 -d ' '`
+OUTPUT=`xrandr|grep ' connected'|grep 'primary'|cut -d' ' -f 1`
 GAP=0.1
 NEWVALUE=${CURRENT}
 
@@ -16,7 +17,8 @@ case $1 in
     ;;
     read)
         echo "${CURRENT}*100/1"|bc
+        exit 0
     ;;
 esac
 
-xrandr --output eDP-1 --brightness ${NEWVALUE}
+xrandr --output ${OUTPUT} --brightness ${NEWVALUE}