开启背光灯：sl on  或者 sl ON

 关闭背光等：sl off  或者 sl OFF

#!/bin/bash  if [ "$1" = "on" ] ||[ "$1" = "ON" ]; then     xset led  named 'Scroll Lock' elif [ "$1" = "off" ] ||[ "$1" = "OFF" ]; then     xset -led named 'Scroll Lock' else     echo "Usage: $0 on/off"     exit 1 fi exit 0