title: Command to refresh output of other command
body: <p>If I have a command that each time gives me a output, (a status, for example). How I can do it to refresh this output every 2 seconds, for example? I remember that there is one command which can do it.</p>
  <p>Example:</p>
  <pre><code>cat /proc/mdstat 
  
  [======&gt;..............]  resync = 30.8% (150544832/488383936) finish=65.8min speed=85472K/sec
  
  othercommand cat /proc/mdstat
  </code></pre>