title: File.mkdir or mkdirs return false - Reason?
body: <p>Why file.mkdir is returning false?</p>
  
  <p>Google indicates that there could be several reasons (e.g. security, permissions, pathname, etc). </p>
  
  <p>My questions:</p>
  
  <ol>
  <li>How to find the exact reason of returning false?</li>
  <li>If security/permissions is a reason, then why is SecurityException not thrown?</li>
  </ol>