Problem with a UDP connection between two programs

[caduel]

a) You should separate the hardware dependent code from the network/server layer.
That way you can test the server part independently from the hardware part.

b) Have you tried the code at QUdpSocket? Does your "read-slot" get called? Ever?

[fraubrj]

OK, find attached files Test_A and Test_B in Test_A_B.zip
The slot " udpRxEvent() " of the program A is never called.

[fraubrj]

Here is the C# version of B program (without hardware dependent code)
You can verify that the program A (Qt) works perfectly with this program B (C#)

[fraubrj]

I finaly found solution all is on the run()

QTextStream out( stdout ); 
 
	QUdpSocket m_socket;
	QByteArray datagram;
	QHostAddress sender;
	quint16 senderPort;
	QString in_qstr;
	QString resp;
 
    if (m_socket.bind(QHostAddress::Any, 55667) == -1) {
        qDebug("Could not bind udp command_server socket...");
        m_thread_go = false;
    }
    else
        m_thread_go = true;
 
	while (m_thread_go) {
 
        if (m_socket.waitForReadyRead(100)) {
			if (m_socket.hasPendingDatagrams()) {
				datagram.resize(m_socket.pendingDatagramSize());
				m_socket.readDatagram(datagram.data(), datagram.size(), &sender, &senderPort);
				in_qstr = datagram.data();
 
				resp = ProcessCommand(in_qstr.toLower());
 
				datagram.clear();
				datagram.append(resp);
 
				if (m_socket.writeDatagram(datagram, sender, senderPort) == -1) {
					qDebug("dropped at write");
					m_socket.close();
					return;
				}
				if (resp  == "_exit_") {
					m_socket.close();
					m_thread_go = false;
					emit exitCommand();
				}
				m_socket.flush();
			}
		}
    }
    m_socket.close();
}

QTextStream out( stdout ); 
	
	QUdpSocket m_socket;
	QByteArray datagram;
	QHostAddress sender;
	quint16 senderPort;
	QString in_qstr;
	QString resp;

    if (m_socket.bind(QHostAddress::Any, 55667) == -1) {
        qDebug("Could not bind udp command_server socket...");
        m_thread_go = false;
    }
    else
        m_thread_go = true;
		
	while (m_thread_go) {
		
        if (m_socket.waitForReadyRead(100)) {
			if (m_socket.hasPendingDatagrams()) {
				datagram.resize(m_socket.pendingDatagramSize());
				m_socket.readDatagram(datagram.data(), datagram.size(), &sender, &senderPort);
				in_qstr = datagram.data();

				resp = ProcessCommand(in_qstr.toLower());
			
				datagram.clear();
				datagram.append(resp);

				if (m_socket.writeDatagram(datagram, sender, senderPort) == -1) {
					qDebug("dropped at write");
					m_socket.close();
					return;
				}
				if (resp  == "_exit_") {
					m_socket.close();
					m_thread_go = false;
					emit exitCommand();
				}
				m_socket.flush();
			}
		}
    }
    m_socket.close();
}

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