title: FFMPEG interactive Mode help options
body: <p>While streaming a simple command like below</p>
  
  <pre><code>ffmpeg -i "Alien.mkv" -f webm tcp://localhost:8080/listen.webm
  </code></pre>
  
  <p>if I press '?' ffmpeg seems to have an interactive mode with the below options</p>
  
  <pre><code>   ?      show this help
  
     +      increase verbosity 
  
     -      decrease verbosity 
  
     c      Send command to first matching filter supporting it 
  
     C      Send/Queue command to all matching filters 
  
     D      cycle through available debug modes
  
     h      dump packets/hex press to cycle through the 3 states 
  
     q      quit 
  
     s      Show QP histogram
  </code></pre>
  
  <p>I was curious about option 'c'</p>
  
  <p>Does this mean that I can execute further commands on the running stream? Say for instance seeking a new position in a running stream? (I realise you wouldn't normally do this)</p>
  
  <p>I don't really know anything about these and couldn't find much in the ffmpeg documentation or else where. If I press 'c' it suggests the syntax I should use is:</p>
  
  <pre><code>Enter command: &lt;target&gt;|all &lt;time&gt;|-1 &lt;command&gt;[ &lt;argument&gt;]
  </code></pre>
  
  <p>but I still don't really understand how to execute a command. Would someone please give a few examples? I suspect that this isn't used much. </p>