Raspberry Pi: 'tv off' and 'tv on' function

rpi-tv-switch.sh

function tv () {
  if (which tvservice fbset xrefresh 2>/dev/null); then
	  case "${1}" in
	      off|OFF|Off|0) 
		      tvservice -o
		      ;;
  	    on|ON|On|1) 
		      tvservice -p
		      fbset -depth 8
		      fbset -depth 16
		      DISPLAY="${DISPLAY:-:0}" xrefresh
  		    ;;
	      *) echo "(no comprende: $1)" 1>&2;;
	  esac
	else
	  return 1
	fi
}