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[SOLVED] QUDPSocket Help

  • All I am trying to learn QUDPSocket and attempting to write an application to push data back and forth across a network between laptops. Nothing fancy just messages, but I want to send a msg from one system and catch it on the other. I found a nice example on line and it works but it seems to write and read the datagrams on the same system. So I have tried to bind the IPs of the two systems and I get nothing. I am sure I am missing something. Here is my code.

    MyUDP::MyUDP(QObject *parent) : QObject(parent)

    socket = new QUdpSocket(this); 
    socket->connectToHost(QHostAddress(“”), 1234, QIODevice::ReadWrite); 
     connect(socket, SIGNAL), this, SLOT)); 


    void MyUDP::WriteData()


    QByteArray data;

    data.append(“Data In”);

    socket->writeDatagram(data, QHostAddress::LocalHost, 1234);

    //this writes and reads fine. 


    void MyUDP::WriteData(QByteArray inMessage)


    socket->writeDatagram(inMessage, QHostAddress(“”), 1234);


    void MyUDP::readyRead()
    QByteArray Buffer;
    Buffer.resize(socket->pendingDatagramSize()); //Pending DatagramSize is size of incoming data
    QHostAddress sender;
    quint16 senderPort;
    socket->readDatagram(Buffer.data(), Buffer.size(), &sender, &senderPort);
    //Process packets here.

    qDebug() << “Message from : “ << sender.toString();

    qDebug() << “Message Port : “ << senderPort;
    qDebug() << “Message : “ << Buffer;

  • Sorry the code is postings strange. I tried to edit it several times.

  • Qt Champions 2017

    Can you check the network setup ? Can you check whether client box and server box in same network ? Do you have reachability to both boxes ?Are they in same network ?Can you ping each IP address from each box ?

  • Yes I have pinged from both machines and they are on the same network. Once is connected through a wireless connection if that makes a difference, but I can still ping it.

  • Qt Champions 2017

    Difficult to see your code. I can send you the working code. Can you drop email to me ?

  • No problem what is your email?

  • Qt Champions 2017

    Just dropped an in mail for you. You can drop me an email.

  • I sent you a message with my email. Let me know if you received it.

  • I solved the issue. The server has to be set to LocalHost. then the client connects with the IP address. Everything seems to be listening properly.

  • I just sent another email

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