title: avformat_open_input return value, error code on NaCl Module
body: <p>I'm trying to port FFmpeg into my NaCl module.</p>
  
  <p>So far, my module linked ffmpeg and SDL libraries.</p>
  
  <p>It already can play YUV format video which is directed load into memory and copy into YUVOverlay buffer (it's very easy).</p>
  
  <p>Now, I want to use ffmpeg to decode video, but when I call the function <strong>avformat_open_input</strong> it returns <code>-5</code> when input is <em>URL string</em>, such as <code>rtmp://</code> or <code>mmsh://</code>; it returns <code>-1052488119</code> when input is <em>file name</em>, such as <code>/saved/tmp</code> (I mount the file system - html5fs).</p>
  
  <hr>
  
  <p>There are some questions:</p>
  
  <ol>
  <li>What means of -5 and -1052488119?</li>
  <li>If file can't open by avformat_open_input, is it possible the input type is from <em>buffer</em> <strong>not</strong> from <em>file name</em> or <em>url string</em>?</li>
  </ol>
  
  <hr>
  
  <p>If I'm not clearly about my question or description, you can tell me.
  If you are doing the same thing or having the same problem, we can discuss together.</p>
  
  <p>Thanks,
  Jar</p>