How to modify "Threaded Fortune Server Example" in order to...

...recieve from client the fortune phrase's index(an integer data es. 'i' for QStringList.at[i]) and the server to answer with the requested phrase at index 'i'.
Could you indicate, in your experience, a way to approach to that problem?
Do I need to re-implement the QTcpSocket class in thread method run()?

Code:

---

void FortuneThread::run()
{
    QTcpSocket tcpSocket;
//! [1] //! [2]
    if (!tcpSocket.setSocketDescriptor(socketDescriptor)) {
        emit error(tcpSocket.error());
        return;
    }
//! [2] //! [3]
 
    QByteArray block;
    QDataStream out(&block, QIODevice::WriteOnly);
    out.setVersion(QDataStream::Qt_4_0);
    out << (quint16)0;
    out << text;
    out.device()->seek(0);
    out << (quint16)(block.size() - sizeof(quint16));
//! [3] //! [4]
 
    tcpSocket.write(block);
    tcpSocket.disconnectFromHost();
    tcpSocket.waitForDisconnected();
}
//! [4]

---

What is the best solution to read data from socket and then write?

I really appreciate your help, thanks.