title: Sending keystroke to a process
body: <p>I want to write a seperate program that can receive commands from network and replay these commands to <code>omxplayer</code>. <code>omxplayer</code> is the video player on raspberry pi, we can control <code>omxplayer</code> via the keystroke. May anyone please suggest some approaches that we can send keystroke event to a running process?</p>
  
  <p>Any suggestions are appreciated. Thanks! </p>