title: Can PHP tell if the server os is 64-bit?
body: <p>I am dealing with Windows here.</p>
  
  <p>I know you can use the <code>$_SERVER['HTTP_USER_AGENT']</code> variable to detect the OS of the browser viewing the page, but is the any way that PHP can detect the server's OS?</p>
  
  <p>For my program's UI I am using a PHP webpage.  I need to read a key in the registry that is in a different location on a 64-bit OS (It is under the <code>Wow6432Node</code> Key).</p>
  
  <p>Can PHP tell what OS it is running on?  Can PHP tell if the OS is 64-bit or 32-bit?</p>