title: php require() stops script, but the file exist
body: <p>There is script which stops when it achieves <code>require</code>. </p>
  
  <pre><code>$fileIsHere='';
  if(file_exists($directory . 'wp-load.php') and file_exists($directory . 'wp-admin/includes/plugin.php') )$fileIsHere='exist';
  file_put_contents('_501_plugins', $fileIsHere );
  require_once( $directory . 'wp-load.php' );
  require_once( $directory . 'wp-admin/includes/plugin.php');
  file_put_contents('_502_plugins', ''  );
  </code></pre>
  
  <p>So here the file <code>_502_plugins</code> not creates and <code>_501_plugins</code> contain 'exist' and I assume that require definitely stops script.  </p>
  
  <ol>
  <li>I've checked that files is in place with file_exist().</li>
  <li>Tried it with <code>try catch</code> but <code>catch()</code> not executing and I cant get error.</li>
  <li>Server log not shows errors.</li>
  <li>Code works on XAMPP, but fails on real server.</li>
  </ol>
  
  <p>PHP 7.2 (not in the safe mode)
  Why <code>require</code> can stop script?</p>