#!/bin/sh

AVAHI=avahi-browse

while getopts "a:" option
do
  case $option in
  a) AVAHI="$OPTARG" ;;
  esac
done

cast_devices=
while IFS=";" read ip; do
  cast_devices="$cast_devices $ip"
done<<EOT
$($AVAHI -tpvlr _googlecast._tcp | grep "^=" | cut -d";" -f8 | sort)
EOT

echo "Cast responses from:$cast_devices"