title: How to tell if ffmpeg errored or not?
body: <p><strong>The Situation:</strong>
  I'm using ffmpeg (via .net) to save video files. I can get the output from ffmpeg but I dont know how can I customize the output to have better result.</p>
  <p><strong>My Problem:</strong>
  My problem is, there is no certain difference between successful and failed operation.</p>
  <blockquote>
  <p><strong>last line of success:</strong></p>
  <p>video:1006kB audio:134kB subtitle:0 global headers:0kB muxing overhead 0.943510%</p>
  <p><strong>last lines from fails</strong></p>
  <p>c:\x\test-9-8/30/2012-9:29:56-AM.mp4: Invalid argument</p>
  <p>rtmp://cdn.tv/cdn-live39/<em>definst</em>/stream01: Unknown error occurred</p>
  </blockquote>
  <p><strong>My Question:</strong>
  Is there an option (or command line parameter) to add some sort of return code (200: success, 500: error, etc)</p>
  <p>Thanks!</p>
  <p>PS: I saw this topic <a href="https://stackoverflow.com/questions/7390720/how-to-tell-if-ffmpeg-errored?rq=1">How to tell if ffmpeg errored?</a> but there is no number before/after last line. I think the last version doesnt have number anymore.</p>