mpd_watchdog.rb

require "socket"

loop do
  begin
    socket = TCPSocket.new("localhost", 6600)

    time = nil

    loop do
      socket.puts "status"
      message, addrinfo = socket.recvmsg
      status = Hash[message.split("\n").map { |line| line.split(": ", 2) }]
      `/etc/init.d/mpd restart` if status["state"] == "play" && time == status["time"]
      time = status["time"]
      sleep 30
    end
  rescue
    sleep 60
  end
end