I wanted to exclude certain clients from connecting to a QTcpServer. In my server, I use the following code:

Qt Code: 
  1. void Server::incomingConnection(int socketDescriptor)
  2. {
  3. 	socket_ = new QTcpSocket(this);
  4.  
  5. 	//Only perform a host look-up, do NOT establish a connection
  6. 	if (!socket_->setSocketDescriptor(socketDescriptor, QAbstractSocket::HostLookupState)) 
  7. 	{
  8. 		emit error(socket_->error());
  9. 		return;
  10.     }   
  11.  
  12. 	QString name = socket_->peerName();
  13.  
  14. 	if (socket_->peerName() == QString("A certain hostname"))	
  15. 	{
  16. 		emit finished();
  17. 		socket_->close();
  18. 		return;
  19. 	}
  20.  
  21. 	//Close socket anyway to be able to establish a connection
  22. 	socket_->close();	
  23.  
  24. 	if (!socket_->setSocketDescriptor(socketDescriptor)) 
  25. 	{
  26. 		emit error(socket_->error());
  27. 		return;
  28.     } 
  29. }
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On the client side:

Qt Code: 
  1. void Client::establishConnection()
  2. {
  3. 	foreach(QString server, servers_)
  4. 	{			
  5. 		socket_->connectToHost(server, port_);
  6.  
  7. 		if (socket_->waitForConnected(100))
  8. 		{
  9. 			connect(socket_, SIGNAL(readyRead()), this, SLOT(readyRead()));
  10.  
  11. 			emit connectionEstablished(server);			
  12.  
  13. 			break;
  14. 		}		
  15. 	}
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Now it seems that waitForConnected returns true when only performing the host look-up. I do not want a connection to be established at the client side, if there is no real connection. This does not seem to be the behavior one would expect.

I can off course check of the socket is open afterwards, but shouldn't waitForConnected() only return true when a complete connection has been established?