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copied!<p>Take a look at <a href="http://qextserialport.sourceforge.net/" rel="nofollow noreferrer">QextSerialPort</a>:</p> <blockquote> <p>QextSerialPort is a cross-platform serial port class. This class encapsulates a serial port on both POSIX and Windows systems.</p> </blockquote> <p><a href="http://qextserialport.sourceforge.net/qextserialport-1.1.x/" rel="nofollow noreferrer">QextSerialPort</a> inherits from <a href="http://doc.qtsoftware.com/4.5/qiodevice.html" rel="nofollow noreferrer">QIODevice</a> and makes serial port communications integrate more smoothly with the rest of the Qt API.</p> <p>Also, you could use a message passing scheme for communications between the I/O and GUI threads instead of shared memory. This is often much less error prone. You can use the <a href="http://doc.trolltech.com/4.5/qcoreapplication.html#postEvent" rel="nofollow noreferrer">QApplication::postEvent</a> function to send custom QEvent messages to a QObject to be processed in the GUI thread with the <a href="http://doc.trolltech.com/4.5/qobject.html#customEvent" rel="nofollow noreferrer">QObject::customeEvent</a> handler. It will take care of synchronization for you and alleviate your deadlock problems..</p> <p>Here is a quick and dirty example:</p> <pre><code>class IODataEvent : public QEvent { public: IODataEvent() : QEvent(QEvent::User) {} // put all of your data here }; class IOThread : public QThread { public: IOThread(QObject * parent) : QThread(parent) {} void run() { for (;;) { // do blocking I/O and protocol parsing IODataEvent *event = new IODataEvent; // put all of your data for the GUI into the event qApp->postEvent(parent(), event); // QApplication will take ownership of the event } } }; class GUIObject : public QObject { public: GUIObject() : QObject(), thread(new IOThread(this)) { thread->start() } protected: void customEvent(QEvent *event) { if (QEvent::User == event->type) { IODataEvent *data = (IODataEvent *) event; // get data and update GUI here event->accept(); } else { event->ignore(); } // the event loop will release the IODataEvent memory automatically } private: IOThread *thread; }; </code></pre> <p>Also, Qt 4 <a href="http://doc.trolltech.com/4.5/threads.html#signals-and-slots-across-threads" rel="nofollow noreferrer">supports queing signals and slots across threads</a>.</p>

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