C / C++ / MFC Discussion Boards

Shog⁹23-Jan-02 15:28

23-Jan-02 15:28

As Mr. Dunn mentioned above, Windows 98 is very sensitive to resource leaks. However, you can usually detect when this is happening on Windows 2000 by using the task manager. Display the processes page, use the View->Select Columns menu to display the GDI Objects column, and watch the number for your application. If there is a constant increase while it is running, then you've detected the resource leak (this is safer than running the app in Win95/Win98, since resource leaks can cause those OSs to become unstable).

Once you can quickly identify the resource leak, modify your code by commenting out lines that create and use GDI resources, one at a time. In this way you should be able to identify which resources are not being released.

The method you're describing sounds like it should be working; however, because you're relying on automatic deletion of the objects there is no easy way to verify that it is successful. Inserting temporary DeleteObject() calls before the objects go out of scope might also be a good way to narrow down the search:
VERIFY(gdiObj.DeleteObject());
If this line ASSERT()s, then you've found a problem.

And if you can reduce your problem to a few lines of code (i.e.

<br />
CPen pen(PS_SOLID, 1, RGB(0,255,0));<br />
int nSave = dc.SaveDC();<br />
dc.SelectObject(&pen);<br />
VERIFY(dc.RestoreDC(nSave));<br />
VERIFY(pen.DeleteObject());<br />

) then post it here, & someone will prolly figure it out.

farewell goodnight last one out turn out the lights

Smashing Pumpkins, Tales of a Scorched Earth

Re: Double Buffering vs. Private DC's

Michael Dunn23-Jan-02 19:24

Michael Dunn

23-Jan-02 19:24

So, you're still making a lot of GDI objects, since you repaint the controls often. First thing I'd suggest is to move the GDI objects so they're memeber variables of the control classes, so that you only create the objects once.
And btw, the problem doesn't appear on 2000 because NT doesn't have the 16-bit limitations that 9x does.

--Mike--
"COM didn't solve the old version of DLL hell - it just provided us with a new and improved version of hell."
-- John Simmons, 1/22/2002
My really out-of-date homepage
Sonork - 100.10414 AcidHelm
Big fan of Alyson Hannigan.

Re: Double Buffering vs. Private DC's

Mark Lenz23-Jan-02 11:22

Mark Lenz

23-Jan-02 11:22

I see the problem in Windows 98, but I can't duplicate it in Windows 2000.

Mark Lenz

CDROM Information

Adrian Metcalfe23-Jan-02 4:42

Adrian Metcalfe

23-Jan-02 4:42

Hi,

Does anybody know how to find out from the windows api's if a cdrom drive is a CDR/CDRW drive.

I have used GetDriveType( "D:" ) but this only shows that the drive is a CDROM.

Any ideas ??

Adrian

Re: CDROM Information

moliate23-Jan-02 15:29

moliate

23-Jan-02 15:29

I don't know if this works, but perhaps you could try GetFileAttributes on the drive root and see if the directory is read-only?

/moliate

AFX_EXT_CLASS no assure export

Franck George23-Jan-02 4:25

Franck George

23-Jan-02 4:25

Hello,

I want export a class in a MFC dll...

class AFX_EXT_CLASS CMyClass : public CMyOtherClass // in other dll linked
{
...
};

and after build:

CMyClass.cpp(19) : warning C4273: CMyClass::CMyClass': inconsistent dll linkage. dllexport assumed.
CMyClass_MSA.cpp(28) : warning C4273: CMyClass::~CMyClass': inconsistent dll linkage. dllexport assumed.
Linking...
Creating library ...
MyClass.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) const CMyClass::`vftable'" (__imp_??_7CMyClass@@6B@)

I don't understand. Please, help me!
Thank you.
Friendly.

Cry | :((

Re: AFX_EXT_CLASS no assure export

Joao Vaz23-Jan-02 4:43

Joao Vaz

23-Jan-02 4:43

Try this link from msdn

Re: AFX_EXT_CLASS no assure export

Joao Vaz23-Jan-02 4:46

Joao Vaz

23-Jan-02 4:46

The link didn't show up on reply Confused | :confused:

Again:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vccore98/HTML/_core_export_and_import_using_afx_ext_class.asp

Joao Vaz

Re: AFX_EXT_CLASS no assure export

Member 18414215-Jul-10 0:23

Member 184142

15-Jul-10 0:23

De poco sirve este enlace tronco.
Pure garbage!
Anybody fixed???

PLEASE Help URGENT

Sonu Kapoor23-Jan-02 4:11

Sonu Kapoor

23-Jan-02 4:11

Hi Guys,

did somebody know how to list HTTP Directory.
Please Help its URGENT....

Thanx in advance

Best Regards

Sonu

Visual C++ & OpenGL

Rajveer23-Jan-02 3:16

Rajveer

23-Jan-02 3:16

How do I make a display window using visual C++ which shows OpenGL as a child to the application??

Is MFC thread-safe? DialogBar with DLGTEMPL?

HintiFlo23-Jan-02 2:21

HintiFlo

23-Jan-02 2:21

1.) Is MFC thread-safe by itself?
I played aruond with Joseph Newcomers (veryvery good) Queue-class and dicoverd, that it works fine without any syncs! So I used CLists directly in an MT-App and it works fine!

2.) Can I build a CDialogBAR from an in memory resource, a DLGTEMPLATE?
I prefer memorybased Dialogs then .rc-based one for several reasons and I wanna do so with DialogBars, too. Is it possible?

What do you think about DLGTEMPLATE-Dialogs at all, any pros or contras?

mfg HintiFlo

OnInitDialog called in Release, but not in Debug!

Jonnie White23-Jan-02 0:50

Jonnie White

23-Jan-02 0:50

I've inherited a class CMyPrintDialog from CPrintDialog, and it's initialisation happens in OnInitDialog(). OnInitDialog is only called in the release version. In the debug version, the dialog remains uninitialised!

Does anyone know why?

Thanks

Jonnie

Re: OnInitDialog called in Release, but not in Debug!

Alvaro Mendez23-Jan-02 9:37

Alvaro Mendez

23-Jan-02 9:37

Woah, you mean that if you put a breakpoint inside the OnInitDialog function, it never stops there? The only possible explanation is that it's using another class. Check and make sure you don't already have a class with the same name defined somewhere else. I got bitten by this problem a long time ago -- redefining a class somewhere else with the same name. I don't remember why the compiler or linker never caught it, but it drove me nuts for a long time before I discovered it.

Regards,
Alvaro

Re: OnInitDialog called in Release, but not in Debug!

Shog⁹23-Jan-02 15:38

Shog⁹

23-Jan-02 15:38

I've run into this problem in the past; it appears to be either a bug in some versions of MFC, or small version differences: debug EXEs compiled (and working) on one developer's machine would fail to work on another. Installing the latest service pack fixed it for me. You might also try just re-installing the version you have (if you don't have access to the latest service pack, or have a slow internet connection for instance), but i can't say whether this will have any effect or not.

farewell goodnight last one out turn out the lights

Smashing Pumpkins, Tales of a Scorched Earth

Re: OnInitDialog called in Release, but not in Debug!

Jonnie White24-Jan-02 0:21

Jonnie White

24-Jan-02 0:21

Thanks for your help. It was an MFC bug fixed in the Visual Studio 6.0 Service Pack 1. Works like a dream now.

Jonnie

RegisterClass() in 98..

Neha23-Jan-02 0:51

Neha

23-Jan-02 0:51

Hi,
I have the following code
WNDCLASS wc;

// Source window
wc.style = CS_HREDRAW | CS_VREDRAW;
wc.lpfnWndProc = NULL;//(WNDPROC)SourceWndProc;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;//UD_MAIN_WINDOW_EXTRA_BYTE;
wc.hInstance = A_hInst;
wc.hIcon = LoadIcon( A_hInst, MAKEINTRESOURCE(ICO_UMAXLOGO) );
wc.hCursor = LoadCursor( NULL, IDC_ARROW );
wc.hbrBackground = (HBRUSH) GetStockObject( LTGRAY_BRUSH );
wc.lpszMenuName = NULL;
wc.lpszClassName = kMAIN_WINDOW_CLASS; // define in TW_LAYOT.H
if( !RegisterClass( &wc ) )
return FALSE;

But RegisterClass() fails in windows 98.
Can anyone pl help me.
Neha

Re: RegisterClass() in 98..

Michael P Butler23-Jan-02 0:53

Michael P Butler

23-Jan-02 0:53

Apart from RegisterClassEx being a better function to use, what is the error returned from GetLastError when RegisterClass fails?

Michael Smile | :)

How to configure STLPort ?

Ravish23-Jan-02 0:48

Ravish

23-Jan-02 0:48

I have downloaded & unzipped the STLport library. There are several make files found.What needs to be done , so that I can start using it.

Thanks very much

Re: How to configure STLPort ?

23-Jan-02 2:47

The procedure differs depending on your compiler. There are several good .html docs in the /doc subdirectory of your STLPort directory. For example to build the STLPort for Visual C++ 6, you would go to a command prompt, run VCVARS32.bat to register the build evnironment variables, then run

nmake /f vc6.mak clean all

and watch it compile (takes a few minutes)

In order to use it, you would need to set it in your include search path BEFORE any other paths which would contain another STL implementation.

Application Closing

Micheal John23-Jan-02 0:33

Micheal John

23-Jan-02 0:33

Hi,
Can Any one tell me how can i close one application from other one as i have the path of first application in the second application while sing registry....

Neo.

Re: Application Closing

Vladimir Georgiev23-Jan-02 1:15

Vladimir Georgiev

23-Jan-02 1:15

CWnd pwnd = FindWindow(LPCTSTR lpszClassName, LPCTSTR lpszWindowName );
PostMessage(pwnd->m_hWnd, WM_CLOSE, 0, 0);

You can find lpszClassName and lpszWindowName parameters of FindWindow() with the Spy++ utility from Visual Studio Tools

"Needless redundancy is the hobgoblin of software engineering." - Peter Darnell

Re: Application Closing

NormDroid23-Jan-02 4:38

NormDroid

23-Jan-02 4:38

... or WM_QUIT

Normski. - Professional Windows Programmer

Dynamic resource Declaration

User 2674023-Jan-02 0:00

User 26740

23-Jan-02 0:00

Hi All,
I wanted to defines some BITMAP resources dynamically. If I wanted to display a pre-determined bitmap in my dialogbox, then I define a BITMAP resource and calling LoadBitmap() in pannel of that dialog-box. The defination in project.rc file goes like

IDB_USER_BITMAP BITMAP DISCARDABLE "images_1\\user-pannel.bmp"

What I wanted to achieve here is something like
#define PRODUCT_IMAGE_PATH "images_1"

IDB_USER_BITMAP BITMAP DISCARDABLE PRODUCT_IMAGE_PATH+"\\user-pannel.bmp"

Thus at compile time it decide about resource-id and which resource to incorporate.
I wanted this to make smaller size of my executable as well as eleminating manual task of folders renaming.
Thanks.
-- Sumit

Sumit Pandya

-- modified 1-Aug-19 21:02pm.

Programmatically adding route (CreateIPForwardEntry)

Martijn22-Jan-02 21:54

Martijn

22-Jan-02 21:54

I've got a problem with the API "createipForwardEntry"). I'm trying to add a routing rule in the piece of code hereunder. It works just fine. However, if i use the IP address assigned to my ethernetcard as the "next hop" (thereby making it the default gateway for the particular network segment) it fails me. Can anyone help me out?

<br />
PMIB_IPFORWARDROW pRow = NULL;<br />
ULONG dwSize = 0;<br />
DWORD dwStatus = 0;<br />
<br />
// Allocate some memory to store the row in<br />
pRow = (PMIB_IPFORWARDROW)malloc(sizeof(MIB_IPFORWARDROW));<br />
<br />
if (!pRow) {<br />
MessageBox("Malloc failed, Out of Memory!\r\n");<br />
exit(1);<br />
}<br />
<br />
// changing dwForwardNextHop into anything else works...<br />
// 172.31.64.9 is the ip address assigned (through DHCP) to my ethernetcard.<br />
// route add 172.0.0.0 mask 255.0.0.0 172.31.64.9 metric 30 if 2<br />
// works just fine.<br />
pRow->dwForwardDest = inet_addr("172.0.0.0");<br />
pRow->dwForwardNextHop = inet_addr("172.31.64.9"); // --> this doesn't work, any other value does<br />
pRow->dwForwardMask = inet_addr("255.0.0.0");<br />
pRow->dwForwardIfIndex = 2;<br />
pRow->dwForwardType = 4;<br />
pRow->dwForwardProto = MIB_IPPROTO_NETMGMT;<br />
pRow->dwForwardAge = 0;<br />
pRow->dwForwardMetric1 = 30; <br />
<br />
// Create a new route entry for the default gateway.<br />
dwStatus = createipForwardEntry(pRow);<br />
<br />
if (dwStatus == NO_ERROR)<br />
MessageBox("Route Added Successfully\n");<br />
else if (dwStatus == ERROR_INVALID_PARAMETER)<br />
MessageBox("Invalid Parameter\n");<br />
else <br />
DisplayErrorMessage(dwStatus);<br />
<br />
// Free resources<br />
if (pRow)<br />
free(pRow); <br />

pretty please?

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