Issues with QTcpSocket within QThread
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Thank you Volker for your timely response. I will be trying this very soon to see how it goes. I guess I am still a little boggled due to the fact that I need to flush the tcp buffer before my data actually sends. It might be due to the thread having an internal tcp port.
Hopefully I will have success! Thanks!
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So I apologize for the double post, but I ended up trying this out and this is how I have implemented the socket and thread.
in main cpp file this is how I initialize the signals and slots and my thread:
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connect(&incTcpSocket, SIGNAL(readyRead()), &testThread, SLOT(incTcpReadyReadSignal())); // ready read on tcp socket
connect(&incTcpSocket, SIGNAL(disconnected()), &testThread, SLOT(incTcpSocketDisconnected())); // socket disconnected
// start the tcp thread
incTcpSocket.moveToThread(&testThread); // move events to thread
testThread.start(); // start the thread
@So, I wanted my slots to run in my thread aka so tcp events happen within the thread its self.
The thing is, my tcpSocket has to be global between the two threads for to be able to read and write to the socket within the run() while loop in the QThread (if the tcp socket is defined in the main.cpp, or else the program wont compile and flag errors saying cannot fined object "incTcpSocket"). So instead I had to create a tcpSocket as an extern in a header globalexterns.hpp with a globalexterns.cpp denoted for the global declaration to share between the two threads.
Im am still not recieving the events on my tcp socket for some reason...
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Do you get any output on the console? Errors? Warnings?
Be careful with your testThread object - it is not in the new thread, but in the main thread (where it has been created).
Also, if you access the socket from two different threads, you must protect it with a [[Doc:QMutex]] against simultaneous access!
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So what I have resulting in doing is creating my tcp socket globally (using QMutex to protect the object from simultaneous accessing). My events are connected in the main thread to my main thread ready read slots.
Still, for some reason I have to tcpSocket->flush before all the data is sent out the socket. but if I dont flush, my return from my write function still says I sent the desired amount of byte I was trying to send out.
And my ready read signal is not being triggered for some reason.
Is there any restrictions on creating a socket globally? Or do I have to make a tcp socket a specific way in windows compared to linux (where I have always done them and have never had a problem like this...Ever).
EDIT: the tcp flush, and the tcp write are both being done within the while loop in the thread
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Hard to say what's going wrong.
The best approach would be to boil down your application to a very simple test project, just your main class and the thread and some glue logic, that demonstrates the error.
Just zip everything together (actually not everything but only the sources - .h. + .cpp, and the project file - .pro, no xxx.o or similar compiler output) and upload it somewhere so that we can grab it.s
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I have zipped a sample project which has the same idea what I am trying to accomplish. Hope this helps. Thank you again for your help.
Heres the download link.
http://www.filefactory.com/file/c2cb12e/n/tcpClientTest.rarClick the download link on the bottem...this was the first fileshare site I could find.
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I'll have a look later this week.
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I actually figured out a way around it...I needed a quick solution since this project needs to be done asap. Still not sure why the global tcp socket isn't working but my solution seems to be working. I kept the tcp socket local to the main thread, and used signals to call into my functions that connect, write, etc from my tcp thread. Its just a little complicated since instead of mutex's I had to use quite a bit of booleans to make sure the signals were not being accessed multiple times (for example, waiting to connect has a timeout, I dont want to loop in my thread unless and call the same signal until that whole connect slot has finished).
I would still like to see if I can get my example code to work. I'm finding out my skills with threading in c++ lacking. I thank you again for your time Volker.