title: how to create a RTSP streaming server
body: <p>So I am trying to create a RTSP server that streams music.<br>
  I do not understand how the server plays a music and different requests get what ever is playing at that time.<br>
  so, to organize my questions:<br>
  1) how does the server play a music file?<br>
  2) how does the request to the server look like to get whats currently playing?<br>
  3) what does the response look like to get the music playing in the client that requested the music?</p>