title: Qt - Get hostname & MAC address from IP Adreess
body: <p>In my application I want to get the hostname &amp; MAC address from an IP address (in my LAN).
  I used this code to find the hostname, but nothing appeared in lineedit.</p>
  
  <pre><code>QHostInfo HI;
  QHostAddress HA("192.168.1.1");
  QList&lt;QHostAddress&gt; List;
  List.append(HA);
  HI.setAddresses(List);
  ui-&gt;ledHostname-&gt;setText(HI.hostName());
  </code></pre>