Re: Meaning of .org xxx - C / C++ / MFC Discussion Boards

Re: BYTE* to char* or BYTE* to CString ?

neliocc29-May-05 4:25

29-May-05 4:25

You cannot cast a BYTE* to char* or CString, but you can convert it to char* whit this method:

char* CAST(BYTE* bytes,int numberOfBytes)
{
char *result=new char[numberOfBytes];
for(int i=0;i

Re: BYTE* to char* or BYTE* to CString ?

Bob Stanneveld29-May-05 5:48

Bob Stanneveld

29-May-05 5:48

A BYTE is the same size as a char, hence you can cast a BYTE pointer to a char pointer.
You can even do the following:

<br />
DWORD d[4] = {0};<br />
char* p = (char* d );<br />

The code isn't going to be more nice with such casts, but you can still get away with it..

Blog[^]

get ype of control

rgchezhian28-May-05 1:15

rgchezhian

28-May-05 1:15

I have the Id of a control for IDC_NUM1.

how to identify its type using the ID.

advance thanks if anybody let me know

Regards
Chezhian

Re: get ype of control

Jack Puppy28-May-05 1:48

Jack Puppy

28-May-05 1:48

Use GetDlgItem to get the window handle/object.

Use GetClassName to retrieve the class name.

Pssst. You see that little light on your monitor? That's actually a government installed spy camera. Smile and wave to big brother!

Drag & Drop Controls

laiju28-May-05 0:04

laiju

28-May-05 0:04

Iam using MDI Doc-View architecture.
MY application displays customized controls (not derived from windows controls)on a tool bar.
I need to click on the of the control and drag and drop the control on the client area of the window.
When i drag the cursor should appropriately change to indicate drag operation.
I dont know it should be done in the LbuttonDown and Mouse Move event handlers.But I dont know the exact implementation.I need to know if any articles on this are available.
Please give me the URL.
Thanx in advance

laiju

Meaning of .org xxx

Franz Klein27-May-05 23:21

Franz Klein

27-May-05 23:21

I have been going through some assembly code and have seen the following directive:
.org 497
What does it mean? MASM help says something about a location counter. Is this a register, the EIP or what?

D'Oh! | :doh:

I am the handsome one in the crowd.

Re: Meaning of .org xxx

Gary R. Wheeler28-May-05 2:16

Gary R. Wheeler

28-May-05 2:16

The assembler converts your source statements to machine code, which you can think of as an image of what will get loaded into memory. The .ORG directive sets the next location in that image that the assembler will generate instructions or deposit data. The 'location counter' is the how the assembler keeps track of where it is depositing instructions/data in that image. It is not related to a physical register, and in fact does not exist at runtime.

Software Zen: delete this;

Re: Meaning of .org xxx

Toby Opferman28-May-05 13:57

Toby Opferman

28-May-05 13:57

To further note, "ORG" I believe stands for "ORIGIN" and that yes all code from that point forward will be assembled to that offset location.

So what's it used for? Well, it was most commonly used for what was known as "COM" files (Since they commonly used .COM extension, although the loader does not make a distinquish between EXE and COM extensions themselves it uses image signatures) since they are raw image data that is loaded to offset 256 (The PSP is before this) so ".ORG 256" or ".ORG 100h" is commonly seen in some assembly programs.

The other common practice would be for some type of alignment. As an example for boot sectors the last two bytes around 510 need to be 55h and aah as I remember.

To take a guess at what you're looking at, if you are seeing "ORG 497" perhaps you are looking at a boot sector that is putting some variables before this signature.

8bc7c0ec02c0e404c0cc0680f7018827ebee

converting C++ to VC++

Member 200054927-May-05 18:38

Member 2000549

27-May-05 18:38

i am new in this Sigh | :sigh:

i was studying C++ Unsure | :~

and i studied enough but now we have a project that we should do in visual . i chose DVD rental program there is no internet connecttion or anything i was reading through a visual book there are many forms which one i choose MFC ATL or ActiveX.
thanks in advance

Re: converting C++ to VC++

John M. Drescher27-May-05 21:47

John M. Drescher

27-May-05 21:47

Of the choices above MFC is your best bet.

John

Re: converting C++ to VC++

Trollslayer27-May-05 21:51

Trollslayer

27-May-05 21:51

MFC is, generally speaking, easier. Also, make full use of the articles in here and MSDN[^].
There are a lot of very useful examples in both.

Elaine Rose | [Rose]

The tigress is here Big Grin | :-D

Re: converting C++ to VC++

Member 200054928-May-05 6:56

Member 2000549

28-May-05 6:56

Thank u both for ur help Roll eyes | :rolleyes:

i appretiate it Big Grin | :-D

Image resizing algorithm (bilinear)

Budric B.27-May-05 18:01

Budric B.

27-May-05 18:01

Hi,
Can someone point me to some sites with a good explanation of the bilinear interpolation algorithm to resample images? My searches give me "features" web pages of graphics packages and libraries that implement it, but nothing that explains it well with some pictures and formulas =). I'm hoping someone with experience can point me to a good website on this matter.

What I"m trying to understand is the following quote:
"using bilinear interpolation with a pixel spacing of 1.5 in each direction."

Thanks.

Re: Image resizing algorithm (bilinear)

Andrew Kirillov27-May-05 22:03

Andrew Kirillov

27-May-05 22:03

Hello

Here is an article (the title is "Bicubic", but it's Bilinear):
http://astronomy.swin.edu.au/~pbourke/colour/bicubic/[^]
The approach is implemented in all libraries I've seen.

You can try tool look at Christian's article:
http://www.codeproject.com/cs/media/imageprocessing4.asp[^]

With best regards,
Andrew

Re: Image resizing algorithm (bilinear)

Christian Graus28-May-05 11:57

Christian Graus

28-May-05 11:57

Budric B. wrote:
using bilinear interpolation with a pixel spacing of 1.5 in each direction

Bilinear interpolation means when you do an operation that theoretically requires a pixel position that is not a whole number, you use the fractional part to work out what percentage of surrounding, actual, pixels to use to determine a colour for the pixel that doesn't really exist. As someone else said, I have an article that explains this further and has C# code showing how it is done.

Christian Graus - Microsoft MVP - C++

Re: Image resizing algorithm (bilinear)

C^hris L^osinger29-May-05 5:31

C^hris L^osinger

29-May-05 5:31

Christian Graus wrote:
you use the fractional part to work out what percentage of surrounding, actual, pixels to use to determine a colour for the pixel that doesn't really exist

that actually applies to nearly all interpolation methods. Smile | :)

bi-lin just means using linear interpolation in two dimensions.

(i know you know this - just filling-in)

Cleek | Image Toolkits | Thumbnail maker

Thanks for your replies (nt)

Anonymous29-May-05 4:40

Anonymous

29-May-05 4:40

Point on a line

rocky_pulley27-May-05 16:40

rocky_pulley

27-May-05 16:40

I'm trying to find out if my mouse position is on a specific line. I've tried using the slopes of the line and of the mouse position from the starting point but this doesn't work because when you get close to the starting point and the line is almost horizontal the slopes vary greatly.

Has anyone done this sort of thing before?

Thanks

-- Rocky Dean Pulley

Re: Point on a line

Jack Puppy27-May-05 17:33

Jack Puppy

27-May-05 17:33

I used this article to hit test a line:
Win32: Hit Testing Lines and Curves

Pssst. You see that little light on your monitor? That's actually a government installed spy camera. Smile and wave to big brother!

Re: Point on a line

rocky_pulley28-May-05 4:17

rocky_pulley

28-May-05 4:17

thanks a lot

-- Rocky Dean Pulley

Re: Point on a line

Ted Ferenc28-May-05 4:38

Ted Ferenc

28-May-05 4:38

I did this c. 30 years ago using Fortran, but I can't remember how we did it! and I still have the source code!

The last time I did it I cheated and use PtInRect, I assume the mouse could be X pixels away from the line? If so then just create a bounding rectange and check if the mouse position is within the rectangle or if it must be on the line just make a 1 pixel rectangle.

You will need to 'cheat' slightly the docs state "A point on the right or bottom side is considered outside the rectangle." so make the rectangle 1 pixel too big on these axis.

"An education isn't how much you have committed to memory, or even how much you know. It's being able to differentiate between what you do know and what you don't." - Anatole France

Re: Point on a line

Christian Graus28-May-05 11:59

Christian Graus

28-May-05 11:59

If the line is curved, you need to know the rate of curve. otherwise, it's basic trigonometry.

Christian Graus - Microsoft MVP - C++

LoadFrame Fails on target machine

drallen127-May-05 12:28

drallen1

27-May-05 12:28

I have an MFC Winapp that runs fine on dev machine, but when I deploy to target machine (XP Pro and WinNT) the pMainFrame->LoadFrame(IDR_MAINFRAME) fails. I have a menu, icon and string associated with the resource ID IDR_MAINFRAME.

I have had a heck of a time trying to determine the difference between the dev machine besides the obvious (ie development studio).

Using IDE 2003, unmanaged project.

Any advice or help is much appreciated.

DRA

Throwing Exceptions during Message handling

Uwe Keim27-May-05 12:18

Uwe Keim

27-May-05 12:18

Strange things happen in my C++-MFC-application:

At this position on the call stack I throw a user-defined exception:

>	ProducerUD.exe!Gui::Dialogs::BuildDialog::OnCancel()  Zeile 604	C++
 	mfc71ud.dll!_AfxDispatchCmdMsg(CCmdTarget * pTarget=0x0013ee04, unsigned int nID=0x00000002, int nCode=0x00000000, void (void)* pfn=0x7c295980, ....)  Zeile 89	C++
 	mfc71ud.dll!CCmdTarget::OnCmdMsg(unsigned int nID=0x00000002, int nCode=0x00000000, void * pExtra=0x00000000, AFX_CMDHANDLERINFO * pHandlerInfo=0x00000000)  Zeile 396 + 0x27	C++
 	mfc71ud.dll!CDialog::OnCmdMsg(unsigned int nID=0x00000002, int nCode=0x00000000, void * pExtra=0x00000000, AFX_CMDHANDLERINFO * pHandlerInfo=0x00000000)  Zeile 88 + 0x18	C++
 	mfc71ud.dll!CWnd::OnCommand(unsigned int wParam=0x00000002, long lParam=0x00460622)  Zeile 2550	C++
 	mfc71ud.dll!CWnd::OnWndMsg(unsigned int message=0x00000111, unsigned int wParam=0x00000002, long lParam=0x00460622, long * pResult=0x0013d9e8)  Zeile 1759 + 0x1c	C++
 	mfc71ud.dll!CWnd::WindowProc(unsigned int message=0x00000111, unsigned int wParam=0x00000002, long lParam=0x00460622)  Zeile 1745 + 0x1e	C++
 	zlzwfud.dll!Zeta::Windows::Forms::Specialized::DialogBase::WindowProc(unsigned int message=0x00000111, unsigned int wParam=0x00000002, long lParam=0x00460622)  Zeile 221	C++
 	mfc71ud.dll!AfxCallWndProc(CWnd * pWnd=0x0013ee04, HWND__ * hWnd=0x0116057a, unsigned int nMsg=0x00000111, unsigned int wParam=0x00000002, long lParam=0x00460622)  Zeile 241 + 0x1a	C++
 	mfc71ud.dll!AfxWndProc(HWND__ * hWnd=0x0116057a, unsigned int nMsg=0x00000111, unsigned int wParam=0x00000002, long lParam=0x00460622)  Zeile 389	C++
 	mfc71ud.dll!AfxWndProcBase(HWND__ * hWnd=0x0116057a, unsigned int nMsg=0x00000111, unsigned int wParam=0x00000002, long lParam=0x00460622)  Zeile 209 + 0x15	C++
 	user32.dll!_InternalCallWinProc@20()  + 0x28	
 	user32.dll!_UserCallWinProcCheckWow@32()  + 0xb7	
 	user32.dll!_DispatchClientMessage@20()  + 0x4d	
 	user32.dll!___fnDWORD@4()  + 0x24	
 	ntdll.dll!_KiUserCallbackDispatcher@12()  + 0x13	
 	user32.dll!_NtUserMessageCall@28()  + 0xc	
 	user32.dll!_SendMessageW@16()  + 0x49	
 	comctl32.dll!_Button_NotifyParent@8()  + 0x3d	
 	comctl32.dll!_Button_ReleaseCapture@8()  + 0xd7	
 	comctl32.dll!_Button_WndProc@16()  + 0x842	
 	user32.dll!_InternalCallWinProc@20()  + 0x28	
 	user32.dll!_UserCallWinProcCheckWow@32()  + 0xb7	
 	user32.dll!_DispatchMessageWorker@8()  + 0xdc	
 	user32.dll!_DispatchMessageW@4()  + 0xf	
 	user32.dll!_IsDialogMessageW@8()  + 0xdb	
 	mfc71ud.dll!CWnd::IsDialogMessageW(tagMSG * lpMsg=0x001640e8)  Zeile 200	C++
 	mfc71ud.dll!CWnd::PreTranslateInput(tagMSG * lpMsg=0x001640e8)  Zeile 4512	C++
 	mfc71ud.dll!CDialog::PreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 83	C++
 	zlzwfud.dll!Zeta::Windows::Forms::EnhancedDialog::PreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 194	C++
 	mfc71ud.dll!CWnd::WalkPreTranslateTree(HWND__ * hWndStop=0x004b09e4, tagMSG * pMsg=0x001640e8)  Zeile 3129 + 0x12	C++
 	mfc71ud.dll!AfxInternalPreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 238 + 0x12	C++
 	mfc71ud.dll!CWinThread::PreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 795 + 0x9	C++
 	mfc71ud.dll!AfxPreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 257 + 0xf	C++
 	mfc71ud.dll!AfxInternalPumpMessage()  Zeile 183 + 0x18	C++
 	mfc71ud.dll!CWinThread::PumpMessage()  Zeile 916	C++
 	ZpCommonCoreud.dll!Common::Gui::CoreGuiHelper::Pump(const bool throwStopException=true)  Zeile 286 + 0x1e	C++
 	ZpCommonCoreud.dll!Common::Gui::CoreGuiHelper::Pump()  Zeile 340 + 0x9	C++
 	ProducerUD.exe!Gui::Dialogs::BuildDialog::PumpMessages()  Zeile 492 + 0x8	C++
 	ProducerUD.exe!Gui::Dialogs::BuildDialog::Log(const ATL::CStringT<unsigned short,StrTraitMFC_DLL<unsigned short,ATL::ChTraitsCRT<unsigned short> > > & text={...})  Zeile 497 + 0xd	C++
 	ZpRenderingud.dll!Rendering::RenderEngine::Implementation::CheckForTemplateFileChanges()  Zeile 454 + 0x4a	C++
 	ZpRenderingud.dll!Rendering::RenderEngine::BuildProjectFolder(const long projectFolderID=0x0000006c)  Zeile 1097	C++
 	ProducerUD.exe!Gui::Dialogs::BuildDialog::OnStartProcessing(unsigned int p1=0x00000000, long p2=0x00000000)  Zeile 232 + 0x18	C++
 	mfc71ud.dll!CWnd::OnWndMsg(unsigned int message=0x00008003, unsigned int wParam=0x00000000, long lParam=0x00000000, long * pResult=0x0013ea40)  Zeile 2013 + 0x11	C++
 	mfc71ud.dll!CWnd::WindowProc(unsigned int message=0x00008003, unsigned int wParam=0x00000000, long lParam=0x00000000)  Zeile 1745 + 0x1e	C++
 	zlzwfud.dll!Zeta::Windows::Forms::Specialized::DialogBase::WindowProc(unsigned int message=0x00008003, unsigned int wParam=0x00000000, long lParam=0x00000000)  Zeile 221	C++
 	mfc71ud.dll!AfxCallWndProc(CWnd * pWnd=0x0013ee04, HWND__ * hWnd=0x0116057a, unsigned int nMsg=0x00008003, unsigned int wParam=0x00000000, long lParam=0x00000000)  Zeile 241 + 0x1a	C++
 	mfc71ud.dll!AfxWndProc(HWND__ * hWnd=0x0116057a, unsigned int nMsg=0x00008003, unsigned int wParam=0x00000000, long lParam=0x00000000)  Zeile 389	C++
 	mfc71ud.dll!AfxWndProcBase(HWND__ * hWnd=0x0116057a, unsigned int nMsg=0x00008003, unsigned int wParam=0x00000000, long lParam=0x00000000)  Zeile 209 + 0x15	C++
 	user32.dll!_InternalCallWinProc@20()  + 0x28	
 	user32.dll!_UserCallWinProcCheckWow@32()  + 0xb7	
 	user32.dll!_DispatchMessageWorker@8()  + 0xdc	
 	user32.dll!_DispatchMessageW@4()  + 0xf	
 	mfc71ud.dll!AfxInternalPumpMessage()  Zeile 188	C++
 	mfc71ud.dll!CWinThread::PumpMessage()  Zeile 916	C++
 	mfc71ud.dll!AfxPumpMessage()  Zeile 195 + 0xb	C++
 	mfc71ud.dll!CWnd::RunModalLoop(unsigned long dwFlags=0x00000004)  Zeile 4566 + 0x5	C++
 	mfc71ud.dll!CDialog::DoModal()  Zeile 527 + 0xc	C++
 	zlzwfud.dll!Zeta::Windows::Forms::EnhancedDialog::DoModal()  Zeile 113 + 0x8	C++
 	zlzwfud.dll!Zeta::Windows::Forms::Specialized::DialogBase::ShowModal()  Zeile 69 + 0x8	C++
 	ProducerUD.exe!Framework::ProducerMainWindow::ExecuteGuiBuild()  Zeile 1639 + 0x15	C++
 	ProducerUD.exe!Framework::ProducerMainWindow::OnBuild()  Zeile 1745	C++
 	mfc71ud.dll!_AfxDispatchCmdMsg(CCmdTarget * pTarget=0x03f18588, unsigned int nID=0x00008008, int nCode=0x00000000, void (void)* pfn=0x004031d4, ....)  Zeile 89	C++
 	mfc71ud.dll!CCmdTarget::OnCmdMsg(unsigned int nID=0x00008008, int nCode=0x00000000, void * pExtra=0x00000000, AFX_CMDHANDLERINFO * pHandlerInfo=0x00000000)  Zeile 396 + 0x27	C++
 	mfc71ud.dll!CFrameWnd::OnCmdMsg(unsigned int nID=0x00008008, int nCode=0x00000000, void * pExtra=0x00000000, AFX_CMDHANDLERINFO * pHandlerInfo=0x00000000)  Zeile 897 + 0x18	C++
 	mfc71ud.dll!CWnd::OnCommand(unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 2550	C++
 	mfc71ud.dll!CFrameWnd::OnCommand(unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 320	C++
 	mfc71ud.dll!CWnd::OnWndMsg(unsigned int message=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000, long * pResult=0x0013f4dc)  Zeile 1759 + 0x1c	C++
 	ProducerUD.exe!CXTPFrameWndBase<CFrameWnd>::OnWndMsg(unsigned int message=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000, long * pResult=0x0013f4dc)  Zeile 177	C++
 	mfc71ud.dll!CWnd::WindowProc(unsigned int message=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 1745 + 0x1e	C++
 	ProducerUD.exe!Framework::ProducerMainWindow::WindowProc(unsigned int message=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 442	C++
 	mfc71ud.dll!AfxCallWndProc(CWnd * pWnd=0x03f18588, HWND__ * hWnd=0x004b09e4, unsigned int nMsg=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 241 + 0x1a	C++
 	mfc71ud.dll!AfxWndProc(HWND__ * hWnd=0x004b09e4, unsigned int nMsg=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 389	C++
 	mfc71ud.dll!AfxWndProcBase(HWND__ * hWnd=0x004b09e4, unsigned int nMsg=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 209 + 0x15	C++
 	user32.dll!_InternalCallWinProc@20()  + 0x28	
 	user32.dll!_UserCallWinProcCheckWow@32()  + 0xb7	
 	user32.dll!_CallWindowProcAorW@24()  + 0x51	
 	user32.dll!_CallWindowProcW@20()  + 0x1b	
 	XTP9510Libud.dll!CXTPHookManager::HookWndProc(HWND__ * hWnd=0x004b09e4, unsigned int message=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 106 + 0x1c	C++
 	user32.dll!_InternalCallWinProc@20()  + 0x28	
 	user32.dll!_UserCallWinProcCheckWow@32()  + 0xb7	
 	user32.dll!_CallWindowProcAorW@24()  + 0x51	
 	user32.dll!_CallWindowProcW@20()  + 0x1b	
 	ZpCommonCoreud.dll!Common::Gui::SubclassWindow::WindowProc(unsigned int msg=0x00000111, unsigned int wp=0x00018008, long lp=0x00000000)  Zeile 147 + 0x5c	C++
 	ZpCommonCoreud.dll!Common::Gui::HookWndProc(HWND__ * hwnd=0x004b09e4, unsigned int msg=0x00000111, unsigned int wp=0x00018008, long lp=0x00000000)  Zeile 219 + 0x19	C++
 	user32.dll!_InternalCallWinProc@20()  + 0x28	
 	user32.dll!_UserCallWinProcCheckWow@32()  + 0xb7	
 	user32.dll!_DispatchClientMessage@20()  + 0x4d	
 	user32.dll!___fnDWORD@4()  + 0x24	
 	ntdll.dll!_KiUserCallbackDispatcher@12()  + 0x13	
 	user32.dll!_NtUserTranslateAccelerator@12()  + 0xc	
 	mfc71ud.dll!CFrameWnd::PreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 203 + 0x1b	C++
 	ProducerUD.exe!CXTPFrameWndBase<CFrameWnd>::PreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 144 + 0xc	C++
 	ProducerUD.exe!Framework::ProducerMainWindow::PreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 1142	C++
 	mfc71ud.dll!CWnd::WalkPreTranslateTree(HWND__ * hWndStop=0x004b09e4, tagMSG * pMsg=0x001640e8)  Zeile 3129 + 0x12	C++
 	mfc71ud.dll!AfxInternalPreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 238 + 0x12	C++
 	mfc71ud.dll!CWinThread::PreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 795 + 0x9	C++
 	mfc71ud.dll!AfxPreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 257 + 0xf	C++
 	mfc71ud.dll!AfxInternalPumpMessage()  Zeile 183 + 0x18	C++
 	mfc71ud.dll!CWinThread::PumpMessage()  Zeile 916	C++
 	mfc71ud.dll!CWinThread::Run()  Zeile 637 + 0xb	C++
 	mfc71ud.dll!CWinApp::Run()  Zeile 701	C++
 	mfc71ud.dll!AfxWinMain(HINSTANCE__ * hInstance=0x00400000, HINSTANCE__ * hPrevInstance=0x00000000, wchar_t * lpCmdLine=0x00020dfc, int nCmdShow=0x00000001)  Zeile 49 + 0xb	C++
 	ProducerUD.exe!wWinMain(HINSTANCE__ * hInstance=0x00400000, HINSTANCE__ * hPrevInstance=0x00000000, wchar_t * lpCmdLine=0x00020dfc, int nCmdShow=0x00000001)  Zeile 25	C++
 	ProducerUD.exe!wWinMainCRTStartup()  Zeile 390 + 0x39	C
 	kernel32.dll!_BaseProcessStart@4()  + 0x23

Now the exception is correctly catched by my application and it continues to work, but when leaving the main message handler at this point:

>	ProducerUD.exe!Framework::ProducerMainWindow::OnBuild()  Zeile 1748	C++
 	mfc71ud.dll!_AfxDispatchCmdMsg(CCmdTarget * pTarget=0x03f18588, unsigned int nID=0x00008008, int nCode=0x00000000, void (void)* pfn=0x004031d4, ....)  Zeile 89	C++
 	mfc71ud.dll!CCmdTarget::OnCmdMsg(unsigned int nID=0x00008008, int nCode=0x00000000, void * pExtra=0x00000000, AFX_CMDHANDLERINFO * pHandlerInfo=0x00000000)  Zeile 396 + 0x27	C++
 	mfc71ud.dll!CFrameWnd::OnCmdMsg(unsigned int nID=0x00008008, int nCode=0x00000000, void * pExtra=0x00000000, AFX_CMDHANDLERINFO * pHandlerInfo=0x00000000)  Zeile 897 + 0x18	C++
 	mfc71ud.dll!CWnd::OnCommand(unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 2550	C++
 	mfc71ud.dll!CFrameWnd::OnCommand(unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 320	C++
 	mfc71ud.dll!CWnd::OnWndMsg(unsigned int message=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000, long * pResult=0x0013f4dc)  Zeile 1759 + 0x1c	C++
 	ProducerUD.exe!CXTPFrameWndBase<CFrameWnd>::OnWndMsg(unsigned int message=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000, long * pResult=0x0013f4dc)  Zeile 177	C++
 	mfc71ud.dll!CWnd::WindowProc(unsigned int message=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 1745 + 0x1e	C++
 	ProducerUD.exe!Framework::ProducerMainWindow::WindowProc(unsigned int message=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 442	C++
 	mfc71ud.dll!AfxCallWndProc(CWnd * pWnd=0x03f18588, HWND__ * hWnd=0x004b09e4, unsigned int nMsg=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 241 + 0x1a	C++
 	mfc71ud.dll!AfxWndProc(HWND__ * hWnd=0x004b09e4, unsigned int nMsg=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 389	C++
 	mfc71ud.dll!AfxWndProcBase(HWND__ * hWnd=0x004b09e4, unsigned int nMsg=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 209 + 0x15	C++
 	user32.dll!_InternalCallWinProc@20()  + 0x28	
 	user32.dll!_UserCallWinProcCheckWow@32()  + 0xb7	
 	user32.dll!_CallWindowProcAorW@24()  + 0x51	
 	user32.dll!_CallWindowProcW@20()  + 0x1b	
 	XTP9510Libud.dll!CXTPHookManager::HookWndProc(HWND__ * hWnd=0x004b09e4, unsigned int message=0x00000111, unsigned int wParam=0x00018008, long lParam=0x00000000)  Zeile 106 + 0x1c	C++
 	user32.dll!_InternalCallWinProc@20()  + 0x28	
 	user32.dll!_UserCallWinProcCheckWow@32()  + 0xb7	
 	user32.dll!_CallWindowProcAorW@24()  + 0x51	
 	user32.dll!_CallWindowProcW@20()  + 0x1b	
 	ZpCommonCoreud.dll!Common::Gui::SubclassWindow::WindowProc(unsigned int msg=0x00000111, unsigned int wp=0x00018008, long lp=0x00000000)  Zeile 147 + 0x5c	C++
 	ZpCommonCoreud.dll!Common::Gui::HookWndProc(HWND__ * hwnd=0x004b09e4, unsigned int msg=0x00000111, unsigned int wp=0x00018008, long lp=0x00000000)  Zeile 219 + 0x19	C++
 	user32.dll!_InternalCallWinProc@20()  + 0x28	
 	user32.dll!_UserCallWinProcCheckWow@32()  + 0xb7	
 	user32.dll!_DispatchClientMessage@20()  + 0x4d	
 	user32.dll!___fnDWORD@4()  + 0x24	
 	ntdll.dll!_KiUserCallbackDispatcher@12()  + 0x13	
 	user32.dll!_NtUserTranslateAccelerator@12()  + 0xc	
 	mfc71ud.dll!CFrameWnd::PreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 203 + 0x1b	C++
 	ProducerUD.exe!CXTPFrameWndBase<CFrameWnd>::PreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 144 + 0xc	C++
 	ProducerUD.exe!Framework::ProducerMainWindow::PreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 1142	C++
 	mfc71ud.dll!CWnd::WalkPreTranslateTree(HWND__ * hWndStop=0x004b09e4, tagMSG * pMsg=0x001640e8)  Zeile 3129 + 0x12	C++
 	mfc71ud.dll!AfxInternalPreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 238 + 0x12	C++
 	mfc71ud.dll!CWinThread::PreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 795 + 0x9	C++
 	mfc71ud.dll!AfxPreTranslateMessage(tagMSG * pMsg=0x001640e8)  Zeile 257 + 0xf	C++
 	mfc71ud.dll!AfxInternalPumpMessage()  Zeile 183 + 0x18	C++
 	mfc71ud.dll!CWinThread::PumpMessage()  Zeile 916	C++
 	mfc71ud.dll!CWinThread::Run()  Zeile 637 + 0xb	C++
 	mfc71ud.dll!CWinApp::Run()  Zeile 701	C++
 	mfc71ud.dll!AfxWinMain(HINSTANCE__ * hInstance=0x00400000, HINSTANCE__ * hPrevInstance=0x00000000, wchar_t * lpCmdLine=0x00020dfc, int nCmdShow=0x00000001)  Zeile 49 + 0xb	C++
 	ProducerUD.exe!wWinMain(HINSTANCE__ * hInstance=0x00400000, HINSTANCE__ * hPrevInstance=0x00000000, wchar_t * lpCmdLine=0x00020dfc, int nCmdShow=0x00000001)  Zeile 25	C++
 	ProducerUD.exe!wWinMainCRTStartup()  Zeile 390 + 0x39	C
 	kernel32.dll!_BaseProcessStart@4()  + 0x23

Something gets wrong and I end up with the following call stack:

>	cccccccc()	
	ntdll.dll!ExecuteHandler2@20()  + 0x26	
	ntdll.dll!ExecuteHandler@20()  + 0x24	
	ntdll.dll!_KiUserExceptionDispatcher@8()  + 0xe

Alternatively, when not installing a customer error handler with _se_set_translator, I end up with the following call stack:

>	cccccccc()

Which, of course leads to those ugly access violations and terminates my application.

Question:

Is anyone of you aware of some circumstances where it could be unsafe to throw exception during processing windows messages? Maybe I throw away some window handle where the associated WindowProc still tries to send messages to that window? Or something similar? Or something completely different?

I'm really really clueless Confused | :confused:

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Re: Throwing Exceptions during Message handling

Uwe Keim27-May-05 13:13

Uwe Keim

27-May-05 13:13

Replying to myself Smile | :)

Just found the following quote:

When programming for Windows, it is important to remember that exceptions cannot cross the boundary of a "callback." In other words, if an exception occurs within the scope of a message or command handler, it must be caught there, before the next message is processed.

Source: http://www.microsoft.com/msj/archive/S204D.aspx [^]

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