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    <p>If you have followed the fortune client/server examples, you should have a QTcpServer (<code>Rfserver</code>) with a QThread subclass (<code>Rfdevice</code>, its instance variable is called <code>thread</code> in the following code) that contains a QTcpSocket (<code>listenSocket</code>).</p> <p>Having said that, in your server class, listen for incoming connections, my setup looks like this:</p> <pre><code>void Rfserver::incomingConnection(int socketDescriptor){ if(thread){ //if thread exists, there is probably still an open connection if(thread-&gt;listenSocket){//if thread exists and the listenSocket is filled, there is definately an open connection if(thread-&gt;listenSocket-&gt;state() == QAbstractSocket::UnconnectedState){ //but alas, it could just be in the unconnected state, if so kill it. this-&gt;disconnect(); thread-&gt;terminate(); thread=0; connected=false; }//otherwise, do nothing, because the software is happily connected to a device } } if(!thread){ //if no thread exists, we are by no means connected thread = new rfdevice(socketDescriptor, this); //set up a new thread //this first connection communicates the string from your socket to the server parent...use it if you want. connect( thread, SIGNAL(RemoteButton(QString)),this,SLOT(remoteButton(QString)),Qt::BlockingQueuedConnection); connect( thread, SIGNAL(error(QTcpSocket::SocketError)),this,SLOT(tcpError(QTcpSocket::SocketError)),Qt::AutoConnection); connect( thread, SIGNAL(finished()), this, SLOT(threadZero())); //I have a threadZero function that deletes all the data then schedules the socket for deletion. thread-&gt;start(); connected=true; QString *welcome = new QString("Enter your password:\r\n"); echoCommand(welcome); //this is a function you will implement that sends the welcome message to the pending device. } } </code></pre> <p>Okay, so now, when a device tries to connect to the server the device is presented with <code>"Enter your password:\r\n"</code>. Your device will respond to this with a password and username perhaps. But the Qt side of things would look like this:</p> <pre><code>/* FUNCTION:read this is a polling runloop that listens for data as long as the socket is connected or connecting. If a write is ever scheduled, it will be called from this runloop.. */ void Rfdevice::read(void){ while((listenSocket-&gt;state() == QAbstractSocket::ConnectedState) || (listenSocket-&gt;state() == QAbstractSocket::ConnectingState)){ //if there is data available to send write it to the socket if(dataToSend) this-&gt;write(); if(listenSocket-&gt;waitForReadyRead(50)) readBytes(); //wait for 50ms for data from the device //if there is ever data available to be read, read it. } } </code></pre> <p>Your device responds with a username/password in the format <code>username---password\r\n</code>. Then the socket does this:</p> <pre><code>/* FUNCTION:readBytes this is like a callback function because it only gets called when there is data available for read. It basically converts the data to a string. */ void Rfdevice::readBytes(void){ QByteArray newData; newData = listenSocket-&gt;readAll(); QString *recieved = new QString(newData); QStringList userAndPass = recieved.split("---");//this is your delimiter QString username = userAndPass.at(0); QString password = userAndPass.at(1); //NOW, check the username and password vs your SQL or wherever it's saved. } </code></pre> <p>The pseudo-code is pretty complete on the particulars. Hopefully you can put it all together! Let me know if you need more code.</p>
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    1. COsweet ty that helped a lot :-)
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