CreateThread

[rafraf]

I do not understand why my program blocks when processing a long routine eventhough I use CreateThread...any clue??

m_hThread = CreateThread( 0,
0,
ThreadFunc,
(LPVOID)Param,
0,
&m_dwThreadID);

The ThreadFunc is accessed but my dialog remains blocked until the end of the process...

[NoHero]

Without seeing your full code me may won't find the problem. But use code tags when posting code!

[rafraf]

This is practically the whole thing I do to call this thread...from the main thread I call this funcion (funcA). Then I pass some parameters using Param.

HANDLE ThreadClass::funcA(BYTE node, WORD time) 
{
   DWORD Param;
   Param =(6<<24)|(node<<16)|(time);

   m_hThread = CreateThread (0,
                          0,
                          ThreadFunc,
                          (LPVOID)Param,
                          0,
                          &m_dwThreadID);

   if(!m_hThread)
   {
       // Could not create thread		
       return false;
   }
   return m_hThread;              
}


DWORD WINAPI ThreadClass::ThreadFunc(LPVOID pvParam)
{		
	BYTE func_nr = ((DWORD)pvParam>>24)&0xFF;
	ThreadEventFlag = TRUE;
	MathClass calc;		

	switch((BYTE)func_nr)
	{
	   case 0:
...continue...

[NoHero]

The calling code of where you call funcA might be more interesting. To see what happens after the thread was created.

Code Tags...

[rafraf]

here it goes

...
case ID_TH_SCAN_INJ:
{
   ThreadClass thread;
   int node = GetDlgItemInt(hDlg, IDC_COMBO_ELMB, NULL, NULL);
   int time = GetDlgItemInt(hDlg, IDC_TH_SCAN_TIME, NULL, NULL); // in milliseconds
						
   if(!thread.funcA(node, time))
      MessageBox(NULL, "Thread Error (thread.funcA)", "WRONG PARAMETER", MB_ICONEXCLAMATION | MB_OK);

   return TRUE;
}
break;
...

[rafraf]

I have found that the problem comes out when I use this code (see below) inside my ThreadFunc.
g_hElmbDialog = handle of the dialog I call the thread.
If intead of calling CreateDialog using g_hElmbDialog, I use NULL, it works!!
boh??

g_hWaitBox = CreateDialog(GetModuleHandle(NULL), MAKEINTRESOURCE(IDD_WAITBOX), g_hElmbDialog, (DLGPROC)About);
if(g_hWaitBox != NULL)
   ShowWindow(g_hWaitBox, SW_SHOW);
else
   MessageBox(g_hElmbDialog, "CreateDialog Returned NULL", "Warning!", MB_OK | MB_ICONINFORMATION);

Do you know why??

[NoHero]

I have found that the problem comes out when I use this code (see below) inside my ThreadFunc.
g_hElmbDialog = handle of the dialog I call the thread.
If intead of calling CreateDialog using g_hElmbDialog, I use NULL, it works!!
boh??

g_hWaitBox = CreateDialog(GetModuleHandle(NULL), MAKEINTRESOURCE(IDD_WAITBOX), g_hElmbDialog, (DLGPROC)About);
if(g_hWaitBox != NULL)
   ShowWindow(g_hWaitBox, SW_SHOW);
else
   MessageBox(g_hElmbDialog, "CreateDialog Returned NULL", "Warning!", MB_OK | MB_ICONINFORMATION);

Do you know why??

Because if you show a dialog which is the child of another the parent window get's disabled until the child window has finished. This is the same behaviour as you would display a modal dialog > even if you are in another thread the parent window get's blocked until the child window gets closed.

You see why posting full code?

[rafraf]

Yes...That the parent window gets disabled I knew but that it gets blocked is something new for me...

Thanks for your help!!!

[NoHero]

Yes...That the parent window gets disabled I knew but that it gets blocked is something new for me...

Thanks for your help!!!

You are welcome!