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QSocketNotifier: Socket notifiers cannot be enabled or disabled from another thread

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qthreadqtcpserver
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  • D Dooham
    1 Apr 2019, 17:36

    @CP71 Yeah, seeing that socumntation, I think you are right, but I dont understand why appears that error. I wrote the same code that the example that I saw, and that worked , but when I adapted to my case it failed.

    C Offline
    C Offline
    CP71
    wrote on 1 Apr 2019, 18:53 last edited by
    #9

    @Dooham
    I have a dubt.
    Maybe I’m beeing wrong but I think that your server musn't create TcpSocket but it should waiting a new connection:

    In your server
    QObject::connect( this, SIGNAL(newConnection()), this, SLOT(newConnection()) );

    In newConnection:

    //////////////////////////////////////////////////////////////////////////////////////
    ///
    void MyServer::newConnection()
    {
    QTcpSocket *socket = server->nextPendingConnection();
    if ( socket )
    {
    … doing your procedure
    }
    }

    I don’t see where incomingConnection is called.

    But maybe it is already so.

    D 1 Reply Last reply 1 Apr 2019, 19:09
    1
    • C CP71
      1 Apr 2019, 18:53

      @Dooham
      I have a dubt.
      Maybe I’m beeing wrong but I think that your server musn't create TcpSocket but it should waiting a new connection:

      In your server
      QObject::connect( this, SIGNAL(newConnection()), this, SLOT(newConnection()) );

      In newConnection:

      //////////////////////////////////////////////////////////////////////////////////////
      ///
      void MyServer::newConnection()
      {
      QTcpSocket *socket = server->nextPendingConnection();
      if ( socket )
      {
      … doing your procedure
      }
      }

      I don’t see where incomingConnection is called.

      But maybe it is already so.

      D Offline
      D Offline
      Dooham
      wrote on 1 Apr 2019, 19:09 last edited by
      #10

      @CP71 I think that is not neccesary,because of the function incomingConnection. When I see this Code I had a similar doubt, but this function is a virtual function of QtcpServer that is called when a newConnection Signal appears. In this code,I just edit the function a bit.
      Maybe the trouble would be that I didnt called the write function from the run, and this could be problematic. In a while, I will try to rewrite the code un order to call the function that write the message from the run

      D C 2 Replies Last reply 2 Apr 2019, 07:32
      1
      • S Offline
        S Offline
        SGaist
        Lifetime Qt Champion
        wrote on 1 Apr 2019, 20:11 last edited by
        #11

        Hi,

        Are you trying to implement a threaded server ? If so, you can take a look at the threaded fortune server example.

        Interested in AI ? www.idiap.ch
        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

        D 1 Reply Last reply 1 Apr 2019, 20:39
        2
        • S SGaist
          1 Apr 2019, 20:11

          Hi,

          Are you trying to implement a threaded server ? If so, you can take a look at the threaded fortune server example.

          D Offline
          D Offline
          Dooham
          wrote on 1 Apr 2019, 20:39 last edited by
          #12

          @SGaist Thanks you, I think this example support my idea, that the trouble is that I dont call the function that write the message from the run function but from a external slot that, in theory dont interact with this routine. Am I right?
          On the other hand, do you know any method to initialize the serial port from the thread just one time (at the begginning of the program)? I have been thinking during the last hour but I dont archive any progress
          Thanks again

          1 Reply Last reply
          0
          • S Offline
            S Offline
            SGaist
            Lifetime Qt Champion
            wrote on 1 Apr 2019, 20:42 last edited by
            #13

            What is your exact use of QSerialPort ?

            Interested in AI ? www.idiap.ch
            Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

            D 1 Reply Last reply 1 Apr 2019, 21:10
            1
            • S SGaist
              1 Apr 2019, 20:42

              What is your exact use of QSerialPort ?

              D Offline
              D Offline
              Dooham
              wrote on 1 Apr 2019, 21:10 last edited by
              #14

              @SGaist I read the continuous message that a device (a Pixhawk). Every thing that I receive a package of message ( the serial port send me package of message) in form of QByteArray I send it to a client that can decode them

              1 Reply Last reply
              0
              • D Dooham
                1 Apr 2019, 19:09

                @CP71 I think that is not neccesary,because of the function incomingConnection. When I see this Code I had a similar doubt, but this function is a virtual function of QtcpServer that is called when a newConnection Signal appears. In this code,I just edit the function a bit.
                Maybe the trouble would be that I didnt called the write function from the run, and this could be problematic. In a while, I will try to rewrite the code un order to call the function that write the message from the run

                D Offline
                D Offline
                Dooham
                wrote on 2 Apr 2019, 07:32 last edited by
                #15

                @Dooham That didn't work, I dont know what is the trouble, I have seen that there are two different QThread ID, and that is probably the cause of the issue:
                0_1554190211682_3c2ed1b3-b00e-4493-9839-8182529d1966-image.png
                As you can see, I got the adress of the Thread that I generate with the incomingConnection but, in some point I create an Object that its parent is other QThread.
                I dont know what to do.

                1 Reply Last reply
                0
                • D Dooham
                  1 Apr 2019, 19:09

                  @CP71 I think that is not neccesary,because of the function incomingConnection. When I see this Code I had a similar doubt, but this function is a virtual function of QtcpServer that is called when a newConnection Signal appears. In this code,I just edit the function a bit.
                  Maybe the trouble would be that I didnt called the write function from the run, and this could be problematic. In a while, I will try to rewrite the code un order to call the function that write the message from the run

                  C Offline
                  C Offline
                  CP71
                  wrote on 2 Apr 2019, 08:34 last edited by CP71 4 Feb 2019, 08:36
                  #16

                  @Dooham
                  I think you don't call addPendingConnection or it seems so

                  0_1554194144567_013b5385-d81d-4dd1-be58-d950d072f8e1-image.png

                  1 Reply Last reply
                  0
                  • D Dooham
                    1 Apr 2019, 09:52

                    Hello,
                    I am having this trouble since two days ago and I am not sure how solve this error.
                    I made a code for a server that can handle multiple connections, my goal is to read in the server messages from a device in the serialPort, send this messages to all the clients connected to my server and, from the clients can send message to the device. To do this, I saw that I need programming a Thread that can handle the multiple connections.
                    I made this code:

                    myserver.cpp

                    #include "myserver.h"
                    
                    MyServer::MyServer(QObject *parent) : QTcpServer (parent)
                    {
                    
                    }
                    
                    void MyServer::startServer()
                    {
                        if(!this->listen(QHostAddress::Any, 9999)){
                    qDebug()<<"Server not started";
                        }else {
                    qDebug()<<"Server listening";
                        }
                    }
                    
                    void MyServer::startSerialPort()
                    {
                       mipuerto2 = new MySerialPort;
                       connect(mipuerto2, SIGNAL(msgChanged()), this, SLOT(getMens()));
                       mipuerto2->openSerialPort();
                    }
                    
                    void MyServer::getMens()
                    {
                        arr2=mipuerto2->getMensaje();
                    
                        emit mensChanged(&arr2);
                    }
                    
                    void MyServer::sendMens(QByteArray *arraySend)
                    {
                    mipuerto2->writeMsg(*arraySend);
                    }
                    
                    
                    void MyServer::incomingConnection(int socketDescriptor)
                    {
                    
                    qDebug()<<socketDescriptor<<"Connecting... ";
                    MyThread *thread=new MyThread(socketDescriptor, this);
                    connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater()));
                    connect(this, SIGNAL(mensChanged(QByteArray * )), thread, SLOT(getMsg(QByteArray *)));
                    connect(thread, SIGNAL(mensajeEnviar(QByteArray * )), this,SLOT(sendMens(QByteArray * )));
                    thread->start();
                    
                    }
                    

                    mythread.cpp

                    #include "mythread.h"
                    
                    MyThread::MyThread(int ID, QObject *parent) : QThread(parent)
                    {
                        this->socketDescriptor=ID;
                    
                    }
                    
                    void MyThread::run()
                    {
                    //thread start here
                        qDebug()<<socketDescriptor<< " Starting thread";
                        socket = new QTcpSocket();
                        if(!socket->setSocketDescriptor(this->socketDescriptor)){
                            emit error(socket->error());
                    
                        }
                    
                        connect(socket, SIGNAL(readyRead()), this, SLOT(readyRead()), Qt::DirectConnection);
                        connect(socket, SIGNAL(disconnected()), this, SLOT(disconnected()), Qt::DirectConnection);
                    
                        qDebug() << socketDescriptor<< " Client Connect";
                    
                    
                    
                        exec();
                    }
                    
                    void MyThread::readyRead()
                    {
                    
                        msgSend="";
                       // socket->waitForReadyRead(100);
                        msgSend=socket->readAll();
                    
                            qDebug()<<msgSend.toHex();
                    emit mensajeEnviar(&msgSend);
                    }
                    
                    void MyThread::disconnected()
                    {
                        qDebug() << socketDescriptor<< " Disconnected";
                    
                        socket->deleteLater();
                    
                        exit(0);
                    }
                    
                    void MyThread::getMsg(QByteArray * array)
                    {
                    
                        socket->write(*array);
                        socket->waitForBytesWritten(3000);
                    
                    }
                    

                    So everytime that, the serial port read a new group of messages, emit a signal to send them.
                    With this code, I can read the messages from the client and send message (I haven't probe with more connections yet), but when I read I get this error in the server console:

                    QSocketNotifier: Socket notifiers cannot be enabled or disabled from another thread

                    This error appears every time that a new messages arrives to the server from the serial port. Does anyone know what I can do to solve it?
                    Thanks.

                    D Offline
                    D Offline
                    Dooham
                    wrote on 2 Apr 2019, 08:40 last edited by
                    #17

                    @Dooham @CP71 @SGaist Finally I could "solve" the trouble that I had. I had to create other class that has the QTcpSocket, and create that class inside the run function of the thread as a local variable. However I found some trouble with the write method, I dont know how to solve it. The trouble is that dont read the client (with the previous code I could read, the messaged from the client). This is my code:

                    myserver.cpp

                    MyServer::MyServer(QObject *parent) : QTcpServer (parent)
                    {
                    
                    }
                    
                    void MyServer::startServer()
                    {
                        if(!this->listen(QHostAddress::Any, 9999)){
                    qDebug()<<"Server not started";
                        }else {
                    qDebug()<<"Server listening";
                        }
                    }
                    
                    void MyServer::startSerialPort()
                    {
                       mipuerto2 = new MySerialPort;
                      connect(mipuerto2, SIGNAL(msgChanged(QByteArray*)), this, SLOT(getMens(QByteArray*)));
                       mipuerto2->openSerialPort();
                    }
                    
                    void MyServer::getMens(QByteArray*array)
                    {
                    
                    
                    
                        emit mensChanged(array);
                    }
                    
                    void MyServer::sendMens(QByteArray *arraySend)
                    {
                    mipuerto2->writeMsg(*arraySend);
                    }
                    
                    
                    void MyServer::incomingConnection(int socketDescriptor)
                    {
                    
                    qDebug()<<socketDescriptor<<"Connecting... ";
                    MyThread *thread=new MyThread(socketDescriptor, this);
                    
                    qDebug()<<thread;
                    connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater()));
                    connect(this, SIGNAL(mensChanged(QByteArray * )), thread, SLOT(getMsg(QByteArray *)));
                    connect(thread, SIGNAL(mensajeEnviar(QByteArray * )), this,SLOT(sendMens(QByteArray * )));
                    
                    
                    
                    thread->start();
                    
                    }
                    
                    

                    myserialport.cpp

                    #include "myserialport.h"
                    #include <QObject>
                    #include <QtSerialPort/QSerialPort>
                    #include <QDebug>
                    
                    
                    MySerialPort::MySerialPort()
                    {
                        serial = new QSerialPort(this);
                        data= "";
                    
                        connect(serial, SIGNAL(readyRead()), this, SLOT(readData()));
                        openSerialPort();
                    
                    }
                    
                    void MySerialPort::openSerialPort()
                    {
                        serial->setPortName("COM4");
                        //serial->setBaudRate(QSerialPort::Baud9600);
                        serial->setBaudRate(QSerialPort::Baud115200);
                        serial->setDataBits(QSerialPort::Data8);
                        serial->setParity(QSerialPort::NoParity);
                        serial->setStopBits(QSerialPort::OneStop);
                        serial->setFlowControl(QSerialPort::NoFlowControl);
                        serial->open(QIODevice::ReadWrite);
                    
                    
                    }
                    
                    void MySerialPort::closeSerialPort()
                    {
                        if(serial->isOpen()){
                            serial->close();
                        }
                    }
                    
                    void MySerialPort::readData()
                    {
                    
                       data = serial->readAll();
                        dataAux=data.toHex();
                        emit msgChanged(&data);
                    
                    }
                    
                    QByteArray MySerialPort::getMensaje()
                    {
                        return data;
                    }
                    
                    void MySerialPort::writeMsg(QByteArray datos)
                    {
                    
                        serial->write(datos);
                    
                    }
                    
                    

                    mythread.cpp

                    #include "mythread.h"
                    #include "mysocket.h"
                    MyThread::MyThread(int ID, QObject *parent) : QThread(parent)
                    {
                        this->socketDescriptor=ID;
                    
                    
                    }
                    
                    void MyThread::run()
                    {
                        qDebug()<<socketDescriptor<< " Starting thread";
                        MySocket socket2(this->socketDescriptor);
                        //Revisar mas tarde
                        /*if(!socket2.setSocketDescriptor(this->socketDescriptor)){
                            emit error(socket->error());
                    
                        }*/
                    
                        /*connect(socket2, SIGNAL(readyRead()), this, SLOT(readyRead()), Qt::DirectConnection);*/
                    
                    
                        connect(this, SIGNAL(mensajeRecibido(QByteArray*)), &socket2, SLOT(getMsg(QByteArray*)));
                        connect(&socket2, SIGNAL(disconnected()), this, SLOT(disconnected()));
                        connect(&socket2, SIGNAL(mensajeEnviarSocket(QByteArray*)), this, SLOT(readyRead(QByteArray*)));
                        qDebug() << socketDescriptor<< " Client Connect";
                    
                    
                    
                        exec();
                    }
                    
                    void MyThread::readyRead(QByteArray*arraySent)
                    {
                    
                    
                        qDebug()<<arraySent->toHex();
                        emit mensajeEnviar(arraySent);
                    }
                    
                    void MyThread::disconnected()
                    {
                        qDebug() << socketDescriptor<< " Disconnected";
                    
                        //socket->deleteLater();
                    
                        exit(0);
                    }
                    
                    void MyThread::getMsg(QByteArray * array)
                    {
                        emit mensajeRecibido(array);
                    
                    
                    }
                    

                    mysocket.cpp (This is the new class)

                    #include "mysocket.h"
                    
                    MySocket::MySocket(int socketDescriptor)
                    {
                    socket= new QTcpSocket;
                    socket->setSocketDescriptor(socketDescriptor);
                    connect(this, SIGNAL(disconnected()), this, SLOT(desconexion()));
                    connect(this, SIGNAL(readyRead()), this, SLOT(leerMsg()));
                    qDebug()<<"Hola";
                    }
                    
                    void MySocket::leerMsg()
                    {
                        msgSend="";
                        // socket->waitForReadyRead(100);
                        msgSend=socket->readAll();
                    
                        qDebug()<<msgSend.toHex();
                        emit mensajeEnviarSocket(&msgSend);
                    }
                    
                    void MySocket::desconexion()
                    {
                       socket->deleteLater();
                    }
                    
                    void MySocket::getMsg(QByteArray *array)
                    {
                    
                        arr=*array;
                        //qDebug()<<arr;
                       // qDebug()<<"server a thread";
                        socket->write(arr);
                        socket->flush();
                        socket->waitForBytesWritten(3000);
                    }
                    
                    

                    mysocket.h

                    #ifndef MYSOCKET_H
                    #define MYSOCKET_H
                    
                    #include <QObject>
                    #include <QTcpSocket>
                    
                    class MySocket:public QTcpSocket
                    {
                        Q_OBJECT
                    public:
                        MySocket(int socketDescriptor);
                    signals:
                        void mensajeEnviarSocket(QByteArray *arraySend);
                    
                    public slots:
                        void leerMsg();
                        void desconexion();
                        void getMsg(QByteArray *array);
                    private:
                        QTcpSocket *socket;
                        QByteArray arr;
                        QByteArray msgSend;
                    };
                    
                    #endif // MYSOCKET_H
                    

                    With this code, I can read the serial port and sending to the client without troubles (I also tried with the telnet command and two connections, and this could with them). But I can read the messages sent. Another trouble that I saw, is that, when I disconect the client, in the server appears the following error: QAbstractSocket::waitForBytesWritten() is not allowed in UnconnectedState

                    Does anyone knows how I can solve this issues?
                    Thanks for your help.

                    D 1 Reply Last reply 2 Apr 2019, 09:01
                    0
                    • D Dooham
                      2 Apr 2019, 08:40

                      @Dooham @CP71 @SGaist Finally I could "solve" the trouble that I had. I had to create other class that has the QTcpSocket, and create that class inside the run function of the thread as a local variable. However I found some trouble with the write method, I dont know how to solve it. The trouble is that dont read the client (with the previous code I could read, the messaged from the client). This is my code:

                      myserver.cpp

                      MyServer::MyServer(QObject *parent) : QTcpServer (parent)
                      {
                      
                      }
                      
                      void MyServer::startServer()
                      {
                          if(!this->listen(QHostAddress::Any, 9999)){
                      qDebug()<<"Server not started";
                          }else {
                      qDebug()<<"Server listening";
                          }
                      }
                      
                      void MyServer::startSerialPort()
                      {
                         mipuerto2 = new MySerialPort;
                        connect(mipuerto2, SIGNAL(msgChanged(QByteArray*)), this, SLOT(getMens(QByteArray*)));
                         mipuerto2->openSerialPort();
                      }
                      
                      void MyServer::getMens(QByteArray*array)
                      {
                      
                      
                      
                          emit mensChanged(array);
                      }
                      
                      void MyServer::sendMens(QByteArray *arraySend)
                      {
                      mipuerto2->writeMsg(*arraySend);
                      }
                      
                      
                      void MyServer::incomingConnection(int socketDescriptor)
                      {
                      
                      qDebug()<<socketDescriptor<<"Connecting... ";
                      MyThread *thread=new MyThread(socketDescriptor, this);
                      
                      qDebug()<<thread;
                      connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater()));
                      connect(this, SIGNAL(mensChanged(QByteArray * )), thread, SLOT(getMsg(QByteArray *)));
                      connect(thread, SIGNAL(mensajeEnviar(QByteArray * )), this,SLOT(sendMens(QByteArray * )));
                      
                      
                      
                      thread->start();
                      
                      }
                      
                      

                      myserialport.cpp

                      #include "myserialport.h"
                      #include <QObject>
                      #include <QtSerialPort/QSerialPort>
                      #include <QDebug>
                      
                      
                      MySerialPort::MySerialPort()
                      {
                          serial = new QSerialPort(this);
                          data= "";
                      
                          connect(serial, SIGNAL(readyRead()), this, SLOT(readData()));
                          openSerialPort();
                      
                      }
                      
                      void MySerialPort::openSerialPort()
                      {
                          serial->setPortName("COM4");
                          //serial->setBaudRate(QSerialPort::Baud9600);
                          serial->setBaudRate(QSerialPort::Baud115200);
                          serial->setDataBits(QSerialPort::Data8);
                          serial->setParity(QSerialPort::NoParity);
                          serial->setStopBits(QSerialPort::OneStop);
                          serial->setFlowControl(QSerialPort::NoFlowControl);
                          serial->open(QIODevice::ReadWrite);
                      
                      
                      }
                      
                      void MySerialPort::closeSerialPort()
                      {
                          if(serial->isOpen()){
                              serial->close();
                          }
                      }
                      
                      void MySerialPort::readData()
                      {
                      
                         data = serial->readAll();
                          dataAux=data.toHex();
                          emit msgChanged(&data);
                      
                      }
                      
                      QByteArray MySerialPort::getMensaje()
                      {
                          return data;
                      }
                      
                      void MySerialPort::writeMsg(QByteArray datos)
                      {
                      
                          serial->write(datos);
                      
                      }
                      
                      

                      mythread.cpp

                      #include "mythread.h"
                      #include "mysocket.h"
                      MyThread::MyThread(int ID, QObject *parent) : QThread(parent)
                      {
                          this->socketDescriptor=ID;
                      
                      
                      }
                      
                      void MyThread::run()
                      {
                          qDebug()<<socketDescriptor<< " Starting thread";
                          MySocket socket2(this->socketDescriptor);
                          //Revisar mas tarde
                          /*if(!socket2.setSocketDescriptor(this->socketDescriptor)){
                              emit error(socket->error());
                      
                          }*/
                      
                          /*connect(socket2, SIGNAL(readyRead()), this, SLOT(readyRead()), Qt::DirectConnection);*/
                      
                      
                          connect(this, SIGNAL(mensajeRecibido(QByteArray*)), &socket2, SLOT(getMsg(QByteArray*)));
                          connect(&socket2, SIGNAL(disconnected()), this, SLOT(disconnected()));
                          connect(&socket2, SIGNAL(mensajeEnviarSocket(QByteArray*)), this, SLOT(readyRead(QByteArray*)));
                          qDebug() << socketDescriptor<< " Client Connect";
                      
                      
                      
                          exec();
                      }
                      
                      void MyThread::readyRead(QByteArray*arraySent)
                      {
                      
                      
                          qDebug()<<arraySent->toHex();
                          emit mensajeEnviar(arraySent);
                      }
                      
                      void MyThread::disconnected()
                      {
                          qDebug() << socketDescriptor<< " Disconnected";
                      
                          //socket->deleteLater();
                      
                          exit(0);
                      }
                      
                      void MyThread::getMsg(QByteArray * array)
                      {
                          emit mensajeRecibido(array);
                      
                      
                      }
                      

                      mysocket.cpp (This is the new class)

                      #include "mysocket.h"
                      
                      MySocket::MySocket(int socketDescriptor)
                      {
                      socket= new QTcpSocket;
                      socket->setSocketDescriptor(socketDescriptor);
                      connect(this, SIGNAL(disconnected()), this, SLOT(desconexion()));
                      connect(this, SIGNAL(readyRead()), this, SLOT(leerMsg()));
                      qDebug()<<"Hola";
                      }
                      
                      void MySocket::leerMsg()
                      {
                          msgSend="";
                          // socket->waitForReadyRead(100);
                          msgSend=socket->readAll();
                      
                          qDebug()<<msgSend.toHex();
                          emit mensajeEnviarSocket(&msgSend);
                      }
                      
                      void MySocket::desconexion()
                      {
                         socket->deleteLater();
                      }
                      
                      void MySocket::getMsg(QByteArray *array)
                      {
                      
                          arr=*array;
                          //qDebug()<<arr;
                         // qDebug()<<"server a thread";
                          socket->write(arr);
                          socket->flush();
                          socket->waitForBytesWritten(3000);
                      }
                      
                      

                      mysocket.h

                      #ifndef MYSOCKET_H
                      #define MYSOCKET_H
                      
                      #include <QObject>
                      #include <QTcpSocket>
                      
                      class MySocket:public QTcpSocket
                      {
                          Q_OBJECT
                      public:
                          MySocket(int socketDescriptor);
                      signals:
                          void mensajeEnviarSocket(QByteArray *arraySend);
                      
                      public slots:
                          void leerMsg();
                          void desconexion();
                          void getMsg(QByteArray *array);
                      private:
                          QTcpSocket *socket;
                          QByteArray arr;
                          QByteArray msgSend;
                      };
                      
                      #endif // MYSOCKET_H
                      

                      With this code, I can read the serial port and sending to the client without troubles (I also tried with the telnet command and two connections, and this could with them). But I can read the messages sent. Another trouble that I saw, is that, when I disconect the client, in the server appears the following error: QAbstractSocket::waitForBytesWritten() is not allowed in UnconnectedState

                      Does anyone knows how I can solve this issues?
                      Thanks for your help.

                      D Offline
                      D Offline
                      Dooham
                      wrote on 2 Apr 2019, 09:01 last edited by
                      #18

                      @Dooham I have solved the trouble with waitforBytesWritten with the function: waitforConnected() that return true if is connected so, I just read if the socket is connected. But I cant read yet.

                      C 2 Replies Last reply 2 Apr 2019, 12:41
                      1
                      • D Dooham
                        2 Apr 2019, 09:01

                        @Dooham I have solved the trouble with waitforBytesWritten with the function: waitforConnected() that return true if is connected so, I just read if the socket is connected. But I cant read yet.

                        C Offline
                        C Offline
                        CP71
                        wrote on 2 Apr 2019, 12:41 last edited by
                        #19

                        @Dooham
                        Hi,
                        I quickly watch your code.
                        I see a thing that is a bit dangerous or I think so, you emit a pointer and not a copy of data without thread synchronization, don’t you?

                        D 1 Reply Last reply 2 Apr 2019, 14:29
                        1
                        • D Dooham
                          2 Apr 2019, 09:01

                          @Dooham I have solved the trouble with waitforBytesWritten with the function: waitforConnected() that return true if is connected so, I just read if the socket is connected. But I cant read yet.

                          C Offline
                          C Offline
                          CP71
                          wrote on 2 Apr 2019, 13:03 last edited by
                          #20

                          @Dooham
                          And more,
                          I think you must call addPendingConnection in your incomingConnection

                          void MyServer::incomingConnection(int socketDescriptor)
                          {

                          …

                          addPendingConnection( thread→GetQTcpSocketPointer() )

                          thread->start();

                          }

                          1 Reply Last reply
                          1
                          • C CP71
                            2 Apr 2019, 12:41

                            @Dooham
                            Hi,
                            I quickly watch your code.
                            I see a thing that is a bit dangerous or I think so, you emit a pointer and not a copy of data without thread synchronization, don’t you?

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                            Dooham
                            wrote on 2 Apr 2019, 14:29 last edited by
                            #21

                            @CP71 I dont know if this is dangerous or not, but it is easy to change, I think. So I will change it later to pass a QByteArray and not a QByteArray pointer. Related to pendingConnection, I don know if this is necessary or not. I am just going to have a few connection. I proved ths code with three clients and I didnt have troubles. With the exception that I cant send message to the serialport, but is a problem that dont depend of the number of connections. However I saw that the trouble is that the socket dont emit the signal readyRead in the socket of the server when I receive a message from a client.

                            C 1 Reply Last reply 2 Apr 2019, 17:28
                            1
                            • D Dooham
                              2 Apr 2019, 14:29

                              @CP71 I dont know if this is dangerous or not, but it is easy to change, I think. So I will change it later to pass a QByteArray and not a QByteArray pointer. Related to pendingConnection, I don know if this is necessary or not. I am just going to have a few connection. I proved ths code with three clients and I didnt have troubles. With the exception that I cant send message to the serialport, but is a problem that dont depend of the number of connections. However I saw that the trouble is that the socket dont emit the signal readyRead in the socket of the server when I receive a message from a client.

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                              CP71
                              wrote on 2 Apr 2019, 17:28 last edited by
                              #22

                              @Dooham
                              Ok,
                              When we have some problems we say, “the computer has always reason”, well almost always.
                              I’m joking ;)

                              I already done a TCP Server but I took another road and I hadn't got special problems, so now I haven’t ideas. :(

                              If I can, I suggest you to solve one problem at a time, I would start at the end, as per QtcpSocket, to try to understand why readyRead seems not working I should check the following checks:

                              • Check with Wireshark or other tools if TCP packets arrive to your device
                              • Check by debug text info about QTcpSocket that you have created (e.g. IP of the client)

                              Then climb up to TcpServer.

                              Sorry

                              D 1 Reply Last reply 2 Apr 2019, 17:36
                              1
                              • C CP71
                                2 Apr 2019, 17:28

                                @Dooham
                                Ok,
                                When we have some problems we say, “the computer has always reason”, well almost always.
                                I’m joking ;)

                                I already done a TCP Server but I took another road and I hadn't got special problems, so now I haven’t ideas. :(

                                If I can, I suggest you to solve one problem at a time, I would start at the end, as per QtcpSocket, to try to understand why readyRead seems not working I should check the following checks:

                                • Check with Wireshark or other tools if TCP packets arrive to your device
                                • Check by debug text info about QTcpSocket that you have created (e.g. IP of the client)

                                Then climb up to TcpServer.

                                Sorry

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                                D Offline
                                Dooham
                                wrote on 2 Apr 2019, 17:36 last edited by
                                #23

                                @CP71 Dont worry, you are helpful. I will tried to find the trouble, I know that must be in my Code of the server, because in the first Code that I published in this thread I could do It. And in a simpler Code for just one connection server-client It also worked.

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                                2 Apr 2019, 09:01

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