title: system('php file.php'); doesn't work, why?
body: <p>neither</p>
  
  <pre><code>&lt;?php system('php file.php'); ?&gt;
  </code></pre>
  
  <p>nor</p>
  
  <pre><code>&lt;?php system('/usr/bin/php file.php'); ?&gt;
  </code></pre>
  
  <p>worked. Why?</p>
  
  <p>I tried with <code>-q</code>, with <code>!#/usr/bin/php</code> etc.</p>