QBuffer bytesWritten() problem

[QAlex]

Thanks for the reply!
I apologize for my presumption... you are right!
But I told so, since a friend of mine has the same problem.
We found yesterday a possible workaround of this problem... It seems that connecting the two signals bytesWritten and readyRead, the signal bytesWritten is emitted:

socket = new QBuffer(&pckBuffer,this);
    connect(socket,SIGNAL(bytesWritten(qint64)),pCl,SLOT(SendPck(qint64)));
    connect(socket,SIGNAL(readyRead()),this,SLOT(dummy()));

socket = new QBuffer(&pckBuffer,this);
    connect(socket,SIGNAL(bytesWritten(qint64)),pCl,SLOT(SendPck(qint64)));
    connect(socket,SIGNAL(readyRead()),this,SLOT(dummy()));

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where dummy can be also a slot that does nothing, just like this:

void classname::dummy()
{
}

void classname::dummy()
{
}

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With this configuration, the code works for me and also for my friend.
We don't know exactly why, but the code really works!!! Maybe we will check the reason in the Qt source, as suggested by you!

Best Regards,
Alessandro

[wysota]

I somehow doubt connecting a slot to another signal will start making this signal work.

If you had looked into Qt's source code you would have noticed a construction like this:

#ifndef QT_NO_QOBJECT
    d->writtenSinceLastEmit += len;
    if (d->signalConnectionCount && !d->signalsEmitted && !signalsBlocked()) {
        d->signalsEmitted = true;
        QMetaObject::invokeMethod(this, "_q_emitSignals", Qt::QueuedConnection);
    }
#endif

#ifndef QT_NO_QOBJECT
    d->writtenSinceLastEmit += len;
    if (d->signalConnectionCount && !d->signalsEmitted && !signalsBlocked()) {
        d->signalsEmitted = true;
        QMetaObject::invokeMethod(this, "_q_emitSignals", Qt::QueuedConnection);
    }
#endif

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From this it's obvious you need to return to the event loop for the signal to be emitted. Other signals and slots have nothing to do with this. Also if you took a look at _q_emitSignals() you'd notice that bytesWritten() and readyRead() are always emitted together regardless of actual read and write operations (which makes sense because if you write something to the buffer it can be read back from the buffer immediately). Now inspect your code and determine what is going on there instead of using silly workarounds.