@Mefil
Hello and welcome.

I don't really know what you have in mind. But QLocalSocket behaves just like a socket. It is not message-oriented, it is just a stream of bytes.

You can impose whatever of your own protocol on top if you wish, e.g. precede a "message" you want to send with a byte count. If both ends are using Qt you can use QDataStream to "pack/unpack" structured data.

@VRonin said in problem with QLocalSocket sending continues data to QLocalServer:

This is not correct.

Damn, and sorry! I thought that it had said that, but not. I may have confused with

readyRead() is not emitted recursively; if you reenter the event loop or call waitForReadyRead() inside a slot connected to the readyRead() signal, the signal will not be reemitted (although waitForReadyRead() may still return true).

Simply don't use the waitForFoo() functions to make sure you're running the eventloop. Use signals/slots instead.

@lolopolosko
Oh, I was just about to suggest you buffer all the received data. But as you've solved your problem then my suggestion is moot. I'm glad it works now.

Kind regards.

sender() returns the pointer to the object which emitted the signal (http://doc.qt.io/qt-5.6/qobject.html#sender).
In this case it is a pointer to QLocalSocket, so you need to cast it from QObject* to QLocalSocket* using qobject_cast

@LuGRU
Why not to use: QSharedMemory and You don't need to worry about message formatting.
Because I run process with different account.
First process run from System account and second from local account

When I read SharedMemory in another process I have error "QSharedMemory handle doesn't exist"