[Qt-interest] Can two thread share a QAbstractSocket?

[Gabriele Kahlout]

> A socket descriptor is not a QAbstractSocket. It's like comparing a byte to
> a
> QString.
>

Okay. Qt forbids:
*Note:* It is not possible to initialize two abstract sockets with the same
native socket descriptor.

This is a very subtle note/warning of what I requested to be in the
documentation.

>
> First, I have to question why you need a thread at all. What kind of
> operations do you plan on doing that require a thread?
>

Transfer images. So a client may tell the server, send this image/screenshot
(QByteArray?) to X. Who should receive and serve this call? In the
arcitecture I'm familiar to (the java code) a separate thread handles all of
that.
1. Single thread serving all requests: slow, while a client requested only
to 'login' or a small image, it must wait before a long one of another is
sent. Also, confusing.

2. Spawning  a thread with QtConcurrent.run to serve requests, is the same
as I'm trying to do, only that the thread lives only once.


>
> > The java is:
> >
> > public void run() {
> >  while (true) {
> >                 Socket clientSocket = listener.accept();
> >                 new ClientHandler(clientSocket);
> > }
>
> UDP has no "accept". So I will assume you meant TCP servers.
>

True this code is TCP. However, I'd like to use UDP now, hoping to exploit
that "QAbstractSocket's API unifies most of the differences between the two
protocols".

>
> void SomeObject::slotNewConnection()
> {
>        QTcpSocket *clientSocket = listener->nextPendingConnection();
>        ClientHandler *handler = new ClientHandler;
>
       clientSocket->moveToThread(handler);


 handler->start(); // in my code i put this at the end of the constructor.
Not recommended?

> }
>
> > -----
> > ClientHandler
> >
> > public void run() {
> >  while (true) {
> >
> >             String msg = receive();
> > }
>
> void ClientHandler::run()
> {
>        SomeOtherObject obj;
>
//Why is this needed? Wouldn't  " this-> " do too?

>        obj.connect(clientSocket, SIGNAL(readyRead()),
> SLOT(slotReadyRead()));
>
//or waitForReadyRead().

>        exec();
> }
>
> void SomeOtherObject::slotReadyRead()
> {
>        QByteArray msg = clientSocket->readAll();
> }
>
> Note that the threading bits in my code are completely unnecessary.
>
// u mean the  SomeOtherObject stuff?

>
> PS: please exercise quoting in your replies to emails.
>

What do you mean? I know quoting to mean using quotes "", and to cite
authors of works I refer to. What's the issue here?

> --
> Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
>  Senior Product Manager - Nokia, Qt Development Frameworks
>      PGP/GPG: 0x6EF45358; fingerprint:
>      E067 918B B660 DBD1 105C  966C 33F5 F005 6EF4 5358
>
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>
>


-- 
Regards,
K. Gabriele

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