C / C++ / MFC

Tomasz Sowinski30-Jul-01 9:38

30-Jul-01 9:38

DAMAGE: After Normal block (#17) at 0x00A60DC0

This sounds like heap corruption - the bytes after allocated memory block have been overwritten by your application. In debug mode you're only getting the message, in release this would be probably the application crash. You should use BoundsChecker or Purify to pinpoint the problem.

Tomasz Sowinski -- http://www.shooltz.com

30-Jul-01 16:15

Where would I get BoundsChecker or Purify, and are they free?

Christian Graus30-Jul-01 16:31

Christian Graus

30-Jul-01 16:31

BoundChecker is at www.numega.com, I guess ( i.e. Numega make it ) and your guess on price is out by about a grand ( in Australia anyhow ).

Christian

#include "std_disclaimer.h"

The careful application of terror is also a form of communication.

Eagles may soar, but weasels don't get sucked into jet engines.

Matt Gullett30-Jul-01 17:52

Matt Gullett

30-Jul-01 17:52

The most common cause for this problem is a buffer overflow condition. You probably have either an array or dynamically allocated memory somewhere in your app which you are writing-past in your application.

Example:

char szTemp[20];

for (int iX = 0; iX <= 20; iX++)
{
szTemp[iX] = ' ';
}

This will write past the end of the array and corrupt the stack at offset (szTemp + 20)

should be

char szTemp[20];

for (int iX = 0; iX < 20; iX++)
{
szTemp[iX] = ' ';
}

31-Jul-01 10:50

Ok, that's what my first assumption was also. The problem is that i have almost a hundred arrays doing various things. Do you know of any tricks to help find the location of a memory overwrite/leak in a source file?

Matt Gullett31-Jul-01 13:31

Matt Gullett

31-Jul-01 13:31

Off the top of my head, I can think of 3 things you can try.

1) Make sure your warning level is set to level 4. This will probably not find the error, but its worth a shot and is always a good place to start.

2) If you have access to Purify or BoundsChecker, either will almost always find this kind of problem.

3) This is also not guaranteed, but has proven succesful for me on ocassion. It requires modifying your code, but makes for a simple and performance sensitive check. If you get in the habbit of coding this way, it can solve problems later.

When you have code which reads like below.

char szBuffer[20];

for (int iX = 0; iX < 20; iX++)
{
}

change the code to be

char szBuffer[22];
szBuffer[20] = 0; szBuffer[21] = 255;

for (int iX = 0; iX < 20; iX++)
{
}

ASSERT(szBuffer[21] = 255);

This also mean that when allocating blocks of memory, you will always need to allocate 1 or 2 extra bytes and set the last byte to some value which is unlikely to properly exist in the data. Then before freeing the data, check the value of the last byte for the value you gave it, if its not what you set it to, you just overan your memory.

Note: This is not a guaranteed check because it is possible that the value written into the check byte was the value you put there to begin with, but its still a good preaution.

When is m_wndToolBar initially sized inplace?

Matt Gullett31-Jul-01 13:33

Matt Gullett

31-Jul-01 13:33

oops!

ASSERT(szBuffer[21] = 255);

should have been

ASSERT(szBuffer[21] == 255);

Kristian Nilssen30-Jul-01 7:50

Kristian Nilssen

30-Jul-01 7:50

My CMainFrame class has code to position my docking control bars in OnCreate(). When my app is activated as an active document server, the control bars are created in OnCreateControlBars(). The code to dock each control bar requires m_wndToolBar.GetWindowRect(). The result of GetWindowRect()is silly when called from OnCreateControlBars(). Does anyone know where I should create and position docking control bars when activated as an active doc server?

Remove icon from taskbar

Sreejumon30-Jul-01 7:15

Sreejumon

30-Jul-01 7:15

hi,
I want to remove my mfc application icon from the taskbar.It must be present only in the process list of task manager.ie it must not appear in the application in taskmanager.

Mad | :mad:

Tomasz Sowinski30-Jul-01 7:26

30-Jul-01 7:26

Check KB article Q205158.

Tomasz Sowinski -- http://www.shooltz.com

Sreejumon30-Jul-01 7:33

Sreejumon

30-Jul-01 7:33

Could you please tell the exact location of this article(KB article )

Tomasz Sowinski30-Jul-01 7:38

30-Jul-01 7:38

Search for Q205158 in your VC help or in msdn.microsoft.com. This is the article ID, you should get only relevant hits when searching.

Tomasz Sowinski -- http://www.shooltz.com

Sreejumon30-Jul-01 8:05

Sreejumon

30-Jul-01 8:05

My application is dialog based one.Then how can I include WS_EX_TOOLWINDOW etc???

Tomasz Sowinski30-Jul-01 8:36

Re: CRichEdit & Mouse Move

30-Jul-01 8:36

In CYourApp::InitInstance change this...

CYourDlg dlg;
m_pMainWnd = &dlg;

... to this:

CWnd wndOwner;
static const char * szClass = AfxRegisterWndClass(0);
VERIFY(wndOwner.CreateEx(0, szClass, "x", WS_POPUP, 0, 0, 0, 0, NULL, NULL));
CYourDlg dlg(&wndOwner);
m_pMainWnd = &dlg;

Remove WS_EX_APPWINDOW in CYourDlg::OnInitDialog:

ModifyStyleEx(WS_EX_APPWINDOW, 0);

Tomasz Sowinski -- http://www.shooltz.com

CRichEdit & Mouse Move

AJ12330-Jul-01 6:35

AJ123

30-Jul-01 6:35

Hi,

What the best way of responding to a mouse move, over a CRichEdit.

Cheers

Richard

Kevin Cook30-Jul-01 7:42

Kevin Cook

30-Jul-01 7:42

m_richEditControl.SetEventMask(ENM_MOUSEEVENTS);

Then add this to your message map:

ON_NOTIFY(EN_MSGFILTER, INPUT_WINDOW_ID, MyMsgFilter) // change this line to use your own control ID and filter method name

then you add your method:

void CMyView::OnInputMsgFilter(NMHDR *pNMHDR, LRESULT *pResult)

I can go into more detail on these items, but they should get you pointed in the right direction as is.

VC Project File Format

Steve Thresher30-Jul-01 5:41

Steve Thresher

30-Jul-01 5:41

We currently have over a thousand programs which are currently compiled using command line tools from Borland. It would be nice to convert over to using VC (the DOS editor is getting to the point where it cannot handle the size of the programs!). Has anybody attempted to write a program that will generate the project/workspace files to go with existing source files.

Does anybody know if this is possible or whether there is a quick way to generate the project/workspace files given 2 C source files, a header file and a resource file.

Thanks in advance for any help you can provide.

Steve.

Carlos Antollini30-Jul-01 5:59

Carlos Antollini

30-Jul-01 5:59

File/New/Select Project Tab/win32 Console Application/click in OK
After this select File view. In the project name, make right click and select Add Files to project, add the files .c, the .h, and the .rc

And Ready.

Carlos Antollini.

Steve Thresher30-Jul-01 6:41

Steve Thresher

30-Jul-01 6:41

I know how to setup 1 project. I am looking for a way to setup project/workspace files for over 1000 projects. Fairly painful operation if I have to follow the instructions above that many times.

J Patel30-Jul-01 7:04

J Patel

30-Jul-01 7:04

Have a look at automating such a process, by using the msdev objects.

HTH

Jignesh

J Patel30-Jul-01 10:52

J Patel

30-Jul-01 10:52

I wrote a simple VBS script to automate such a process. This script assumes there are existing files in a certain directory.

This is what I meant by using msdev automation objects.

<br />
' Usage : cscript createproject.vbs<br />
Set objMSDEV = WScript.CreateObject("msdev.application")<br />
objMSDEV.addproject "test","c:\myprogs", "application", TRUE<br />
objMSDEV.ActiveProject.AddFile "test.cpp"<br />
objMSDEV.ActiveProject.AddFile "test.h"<br />
objMSDEV.ActiveProject.AddFile "test.rc"<br />
objMSDEV.Quit<br />
WScript.Echo "Done"<br />
' -----------------<br />
'	End of script<br />
' -----------------<br />

You can tweak this to recurse through numerous folders and add only certain kind of files, or anything else you want.

HTH

Jignesh

Tomasz Sowinski30-Jul-01 7:17

30-Jul-01 7:17

.dsp file is a text which has rather simple structure. You can create empty project and add one or two sources. You'll see that each source file is listed in 'SOURCE=' line. .dsp contains also compiler switches and other stuff which you can just copy - it does not depend on actual source files.

Tomasz Sowinski -- http://www.shooltz.com