title: Symfony Process run as who?
body: <p>When we using <code>Symfony\Component\Process\Process</code>, the command run as who?</p>
  
  <p>I tried the command <code>whoami</code> through <code>Process</code>, but it return void???</p>
  
  <pre><code>$return = exec('whoami');
  echo $return."\n"; // return [myname]
  $process = new Process('whoami'); // The symfony process
  echo $process-&gt;getOutput(); // return nothing @_@
  </code></pre>