Close Thread which manage sockets

[theclem35]

Hello!

I've a multiwindows multithreaded program.
Into a thread, I open socket to receive data with infinite loop. This thread was created by : MyThread = CreateThread(NULL, 0, MySocketsFunction, &MyDatas, 0, NULL);

When user wants stop listening, he clicks on STOP button.
Which makes a : TerminateThread(MyThread,0);


The problem is my thread was listening (recvfrom) on port when it was stopped by TerminateThread.
But as function is suddently stopped, socket is not closed with closesocket(IdMonSocket); because this calling is at the end of the function

So, I can see with netstat -a, that my port is already opened, but thread was terminated.

How can I make to close socket when I terminate thread ?

Thank You!

[CommonTater]

There are lots of sane ways to close a thread... TerminateThread() isn't one of them.

If it has no message handler (i.e. is not tossing messages) the easiest way is to set a global variable ... ThreadStop or such... and use that as the condition in a while() statement... When the stop condition is met you exit your loop and let the thread function return normally.

// at global scope
BOOL ThreadStop = FALSE;

// inside the threadproc
while (!ThreadStop)
  {
      // do winsock stuff
   }
// here you close your ports
ExitThread(0);
}


// user clicks stop button (in main message loop)
case id_Stop :
   ThreadStop = 1;

Of course if the thread is tossing window messages you can just post a message to the message proc that tells it to exit.

[theclem35]

Hello!

Thanks for your answer !
My thread doesn't use tossing window messages.

I try to use global variable at least ! But as I can read, it seems to be the only solution???

How use tossing window messages with threads ?

[Codeplug]

>> the easiest way is to set a global variable ... ThreadStop or such
No, that isn't one of them either. When two or more threads access the same memory location, and at least one is a write access, then you must use synchronization primitives provided by the threading library/compiler.

Here is an example of using a Win32 event object to signal a thread to exit - at which point the thread can perform cleanup before exiting.
Odd Sleep() Within Thread Behavior

http://cboard.cprogramming.com/windows-programming/134597-odd-sleep-within-thread-behavior.html#post1002234

gg