#include <QtNetwork/qabstractsocket.h>
#ifndef QABSTRACTSOCKET_H
class QAbstractSocket: public QIODevice{
   /* Some contents are skipped to improve readability */
   public: enum SocketType{
      TcpSocket = 0,
      UdpSocket = 1,
      UnknownSocketType = -1,
   };
   /* ... */
};
#endif // QABSTRACTSOCKET_H