TCP Two-Way Communication using Qt

I am trying to setup a TCP communication framework between two computers. I would like each computer to send data to the other. So computer A would perform a calculation, and send it to computer B. Computer B would then read this data, perform a calculation using it, and send a result back to computer A. Computer A would wait until it receives something from computer B before proceeding with performing another calculation, and sending it to computer B.

This seems conceptually straightforward, but I haven't been able to locate an example that details two-way (bidirectional) communication via TCP. I've only found one-way server-client communication, where a server sends data to a client. These are some examples that I have looked at closely so far:

I'm basically looking to have two "servers" communicate with each other. The synchronized approach above is, I believe, important for what I'm trying to do. But I'm struggling to setup a two-way communication framework via a single socket.

I would appreciate it greatly if someone could point me to examples that describe how to setup bidirectional communication with TCP, or give me some pointers on how to set this up, from the examples I have linked above. I am very new to TCP and network communication frameworks and there might be a lot that I could be misunderstanding, so it would be great if I could get some clear pointers on how to proceed.

Solution

#include <QAbstractSocket>
#include <QtNetwork>
#include <QTcpServer>
#include <QTcpSocket>

QTcpSocket*   m_pTcpSocket;

Connect to host: set up connections with tcp socket and implement your slots. If data bytes are available readyread() signal will be emmited.

void connectToHost(QString hostname, int port){
    if(!m_pTcpSocket)
{
    m_pTcpSocket = new QTcpSocket(this);
    m_pTcpSocket->setSocketOption(QAbstractSocket::KeepAliveOption,1);
}
connect(m_pTcpSocket,SIGNAL(readyRead()),SLOT(readSocketData()),Qt::UniqueConnection);
connect(m_pTcpSocket,SIGNAL(error(QAbstractSocket::SocketError)),SIGNAL(connectionError(QAbstractSocket::SocketError)),Qt::UniqueConnection);
connect(m_pTcpSocket,SIGNAL(stateChanged(QAbstractSocket::SocketState)),SIGNAL(tcpSocketState(QAbstractSocket::SocketState)),Qt::UniqueConnection);
connect(m_pTcpSocket,SIGNAL(disconnected()),SLOT(onConnectionTerminated()),Qt::UniqueConnection);
connect(m_pTcpSocket,SIGNAL(connected()),SLOT(onConnectionEstablished()),Qt::UniqueConnection);

if(!(QAbstractSocket::ConnectedState == m_pTcpSocket->state())){
    m_pTcpSocket->connectToHost(hostname,port, QIODevice::ReadWrite);
}
}

Write:

void sendMessage(QString msgToSend){
QByteArray l_vDataToBeSent;
QDataStream l_vStream(&l_vDataToBeSent, QIODevice::WriteOnly);
l_vStream.setByteOrder(QDataStream::LittleEndian);
l_vStream << msgToSend.length();
l_vDataToBeSent.append(msgToSend);

m_pTcpSocket->write(l_vDataToBeSent, l_vDataToBeSent.length());
}

Read:

void readSocketData(){
while(m_pTcpSocket->bytesAvailable()){
    QByteArray receivedData = m_pTcpSocket->readAll();       
}
}