title: Convert short/dos style path name to full path name
body: <p>The title says it all. I've seen many solutions to execute the oposite operation but not this way.</p>
  
  <p>I'm using Qt to create a temporary file. If I get its name it will be something on the likes of: </p>
  
  <pre><code>QTemporaryFile tempFile;
  tempFile.open();
  qDebug() &lt;&lt; tempFile.fileName();
  // C:/Users/USERNA~1/AppData/Local/Temp/qt_temp.Hp4264
  </code></pre>
  
  <p>I have tried some solutions such as using QFileInfo:    </p>
  
  <pre><code>QFileInfo fileInfo(tempFile);
  qDebug() &lt;&lt; fileInfo.filePath()
  </code></pre>
  
  <p>And QDir:</p>
  
  <pre><code>QDir dir(tempFile.fileName());  
  qDebug() &lt;&lt; dir.absolutePath();
  </code></pre>
  
  <p>Without success.</p>
  
  <p>Is there any solution for this using purely Qt? I know I can navigate the directory tree to find the full name but I was trying to avoid this, especially because of the possibility of two folders with the same prefix.</p>