title: start /B doesn't start the task
body: <p>I'm currently launching an asynchronous job with PHP to perform some tests.</p>
  
  <p>To make it work, I found on SO some tips, like the use of <code>popen</code> and <code>start</code>:</p>
  
  <pre><code>$commande = "testu.bat";
  $pid = popen('start /B ' . $commande, 'r');
  $status = pclose($pid);
  </code></pre>
  
  <p>The <code>testu.bat</code>'s folder is in my user PATH.</p>
  
  <p>This script performs some task, and to control it's execution, it should generates a log file, but I never get it.</p>
  
  <p>Whereas if I just remove the <code>/B</code> option, it works fine and I get my log file.</p>
  
  <p>Did I miss something about background execution? How can I catch the error informations when it is running in the background?</p>