Re: Retrieving main thread handle or ID - C / C++ / MFC Discussion Boards

9-Nov-01 7:40

Hi,

I'm looking for a way to retrieve the handle or ID of a process main thread.
Can anybody here tell me how to do this?

Regards,

Sebastian

Re: Retrieving main thread handle or ID

Joel Lucsy9-Nov-01 7:47

Joel Lucsy

9-Nov-01 7:47

You mean GetCurrentThread() or GetCurrentThreadId(), or do you mean from a different process?

Joel Lucsy (jjlucsy@concentric.net)

Re: Retrieving main thread handle or ID

9-Nov-01 8:19

I mean the ID of the main thread in a different process.

Sebastian

Re: Retrieving main thread handle or ID

Tim Deveaux10-Nov-01 3:39

Tim Deveaux

10-Nov-01 3:39

If you can identify the main window of the process (bit of a trick in itself) you can call GetWindowThreadProcessId.

Re: Retrieving main thread handle or ID

10-Nov-01 5:46

Hi,

the problem is that I want to identify the main window of the process by comparing its owning-thread ID with the ID of the process main thread...
If you can tell me how to identify the main window, I won't need the main thread ID anymore...

Sebastian

Re: Retrieving main thread handle or ID

Tim Smith10-Nov-01 6:13

Tim Smith

10-Nov-01 6:13

There is no such thing as a 'main window' of a process. So what ever you are trying to do might be flawed by design.

A process can create 0 to N windows.

Tim Smith
Descartes Systems Sciences, Inc.

Re: Retrieving main thread handle or ID

Tim Deveaux10-Nov-01 7:54

Tim Deveaux

10-Nov-01 7:54

Well, I think of the top level window with the caption etc (i.e. CWinThread::m_pMainWnd in the MFC world) as being the 'main' window - the one to close to terminate the app - but I guess you could argue the point.

I've used ::GetTopWindow and ::GetNextWindow to get the top level windows on the desktop, and if you knew, say, the caption of the window you were looking for, you would be able to identify it with ::SendMessage(hwnd,WM_GETTEXT...(yes, keep in mind that there can be more than one 'top level' window in a process).

Given that nasty bit of strongly coupled heuristic hoop jumping through, you might want to add GetWindowThreadProcessId and GetWindowModuleFileName to the mix.

later...
Now that I think of it, for some apps you can eliminate some of the windows that don't return anything for WM_GETTEXT. But Tim has a point - identifying the 'main' window is tricky - you need to have a clue as to the caption or perhaps window class in order to pull this off, I think.

This is a question that's been seen here before, and I don't think a general solution has been proposed. Maybe if you posted more info about your current problem someone might have a specific fix you could use in your situation.

Re: Retrieving main thread handle or ID

10-Nov-01 10:53

First, thank you for your help so far.

Here's some more information about my problem:
I want to fill a list (box) with processes (represented through window titles) to terminate. To perform this task I'm using EnumWindows(). In the EnumWindowsProc I filter out invisible windows, windows without a title, certain window classes (tooltips etc.) and windows that don't return NULL for GetWindow(hWnd, GW_OWNER)...
This works fine if there's only one (top-level) window-owning thread per process. Otherwise more than one window per process passes my EnumWindowsProc. To avoid this I want to filter out all windows created by secondary threads...

Does anybody here know a solution?

Pass array or single HWND into function

9-Nov-01 7:16

Hi

I just wrote a function that hides multiple or a single window(s).
It looks like this:

void HideWindows(HWND wnds)
{...}

but it should work with HWND-arrays ( HWND wnds[20]) same as with a single variable (HWND window).

how can I accomplish this?

thanks in advance

Re: Pass array or single HWND into function

Tim Smith9-Nov-01 7:44

Tim Smith

9-Nov-01 7:44

void HideWindows (HWND *pwnds, int nCount)
{
}

If this is C++, you can add the helper function.

void HideWindows (HWND hWnd)
{
   HideWindows (&hWnd, 1);
}

Tim Smith
Descartes Systems Sciences, Inc.

Re: Pass array or single HWND into function

9-Nov-01 7:50

I can show you what the function does in fact:

void TaskbarOp(BOOL Add, BOOL Multiple, const int IfMultipleThenCount, const HWND *pWindows)
{
	CoInitialize(NULL);
	ITaskbarList *pDisp = NULL;
	CoCreateInstance( CLSID_TaskbarList, NULL, CLSCTX_SERVER, IID_ITaskbarList, (LPVOID *) &pDisp );

	if(Multiple)
	{
		for(int i = 0; i < IfMultipleThenCount; i++)
		{
			if(Add)
				pDisp->AddTab( pWindows[i] );
			else
				pDisp->DeleteTab( pWindows[i] );
		}
	}
	else
	{
		if(Add)
				pDisp->AddTab( pWindows );
			else
				pDisp->DeleteTab( pWindows );
	}

	pDisp->Release();
	CoUninitialize();
}

is there something I should change? There are some error at

else
	{
		if(Add)
				pDisp->AddTab( pWindows ); // error
			else
				pDisp->DeleteTab( pWindows ); // error
	}

Re: Pass array or single HWND into function

Carlos Antollini9-Nov-01 7:57

Carlos Antollini

9-Nov-01 7:57

The diference is that you are passing pWindows.
pWindows is a pointer to HWND and pWindows[i] is a HWND.

Best Regards

Carlos Antollini.

Re: Pass array or single HWND into function

9-Nov-01 7:58

What should I pass then instead of pWindows?

Re: Pass array or single HWND into function

Tim Smith9-Nov-01 8:10

Tim Smith

9-Nov-01 8:10

You are WAY over designing your routine. How about something like this.

void TaskbarOp(BOOL Add, const int nCount, const HWND *pWindows)
{   
    ITaskbarList *pDisp = NULL; 
    CoCreateInstance( CLSID_TaskbarList, NULL, CLSCTX_SERVER, IID_ITaskbarList, (LPVOID *) &pDisp );
    
    for(int i = 0; i < IfMultipleThenCount; i++)        
    {           
        if(Add)             
            pDisp->AddTab( pWindows[i] );           
        else                
            pDisp->DeleteTab( pWindows[i] );        
    }   
    pDisp->Release();   
}

void TaskbarOp(BOOL Add, HWND hWnd)
{
    TaskbarOp(Add, 1, &hWnd);
}

Also, don't call CoInitialize/CoUninitialize like that unless you really really have to. Just call CoInitialize at program start and CoUninitialize at the end.

Tim Smith
Descartes Systems Sciences, Inc.

Thanks!!!

9-Nov-01 8:18

You are ingenious

Thanks a lot! Rose | [Rose]

Destroying / closing windows

ParaSwarm9-Nov-01 6:59

ParaSwarm

9-Nov-01 6:59

I'm writing a program in API (not MFC) and my current dillemma is destroying windows. I know DestroyWindow() destroys it, but then it processes WM_DESTROY and a PostQuitMessage(0) and the whole program exits. I just want to hide or quit the window without the whole program running. If I don't use PostQuitMessage(0), the window disappears but it still exists in the background and runs in the task manager though no windows are apparent, and I dont want that. Whats a good command or way to close or hide a window without quitting the program? Thanks - Dave

Re: Destroying / closing windows

Carlos Antollini9-Nov-01 7:21

Carlos Antollini

9-Nov-01 7:21

What About ShowWindow(SW_HIDE);?

best Regards

Carlos Antollini.

Re: Destroying / closing windows

Nish Nishant9-Nov-01 8:05

Nish Nishant

9-Nov-01 8:05

You can post a WM_CLOSE to that window.

Nish

Sonork ID 100.9786 voidmain

www.busterboy.org

Nish is a BIG fan of Goran Ivanisevic

Registry

Deian9-Nov-01 6:44

Deian

9-Nov-01 6:44

Hello I'm wondering if anyone can help me with the following:

If using RegSetValueEx, to set up a value which holds as hexidecimal this value: 0x00000019(25)-this is how it's supposed to be shown in the regedit. Since it's a dword value i have declared DWORD dw = 19; but it doesen't write it as 0x00000019 (25). When I use the regedit to add it manually it works perfect - I put 25 as decimal and when i change it to hex it's 0x00000019; Any example of doing that programatically?

Thanks,

Deian

PS: Please include everything, declaration of variables, initialization and everything needed Blush | :O

Re: Registry

Carlos Antollini9-Nov-01 7:02

Carlos Antollini

9-Nov-01 7:02

DWORD dwValue = 25;

::RegSetValueEx(m_hKey, (LPCSTR)lpValueName, 0, REG_DWORD, (LPBYTE)&dwValue, sizeof(DWORD))

Best Regards...

Green Alien | [Alien]

Today Is Friday!!! Party and Beer | [beer]

Carlos Antollini.

Is it possible to custom draw the scroll bar in CListCtrl?

RobJones9-Nov-01 3:58

RobJones

9-Nov-01 3:58

Is there a way to change the color of the scroll bar in a list control?

Rob

Disable Help button on the "Customize Toolbar" dialog box

9-Nov-01 3:45

I would disable Help button on the "Customize Toolbar" dialog box
but I wan't use the caption of the control for a code independent of the language.

Thank you for your collaboration. Smile | :)

Help....

sardinka9-Nov-01 3:42

sardinka

9-Nov-01 3:42

Why Insert and Delete is not working?
char *convert_char_modifier(char *Modifier)
{
int i;
char ch;

for (i=0; i < strlen(Modifier);i++)
{
ch = Modifier[i];
switch (ch)
{
case 'A':
//Delete(i);
//Insert(i,"01");
break; Cry | :((

sardinka

Re: Help....

Michael P Butler9-Nov-01 4:06

Michael P Butler

9-Nov-01 4:06

Apart from the fact they are commented out?

I think we'll need to see the code for Delete and Insert too.

Michael Smile | :)

Re: Help....

sardinka9-Nov-01 5:21

sardinka

9-Nov-01 5:21

I comment that line out, but even if I uncomment that line it will not work.
My code is below:
char *convert_char_modifier(char *Modifier)
{ int i;
char ch;
for (i=0; i < strlen(Modifier);i++)
{
ch = Modifier[i];
switch (ch)
{
case 'A':
Insert(i,"01");
break;
case 'B':
Delete(i);
Insert(i,"02");
break; }
}
return(Modifier);

Cry | :((

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