title: Follow the symlink and get the absolute path with QFileInfo
body: <p>I'm coding with C++ and Qt.</p>
  
  <p>I want to follow the symlink and get the absolute path with <code>QFileInfo</code>.</p>
  
  <p>For example, <code>/usr/local/extra</code> is an symlink for <code>/home/extra</code>.
  Then I need to convert <code>/usr/local/extra/my_directory/</code> to <code>/home/extra/my_directory</code>.</p>
  
  <p>I tried <code>QFileInfo(path).canonicalPath()</code> but it returns the parent directory only.</p>