Binary File - C / C++ / MFC Discussion Boards

Sam_c5-Aug-07 23:00

5-Aug-07 23:00

how does Dlg.CaptureImage() return the image data?

by value?

i'm not sure about the error if that isnt the problem.
would need to have access to a compiler which i dont at the moment Sigh | :sigh:

Code Project Lounge 101 by John Cardinal
Beer | [beer]

Re: Heap Corruption

yaminisridaran5-Aug-07 23:31

yaminisridaran

5-Aug-07 23:31

I use delete to free the memory but when i execute delete the exection goes to winheap

S.Yamini

Re: Heap Corruption

jk chan6-Aug-07 0:36

jk chan

6-Aug-07 0:36

Check the return pointer of CaptureImage , is that the same as the orginal (before calling CaptureImage ). Also Try Debugging CaptureImage. the problem is ur trying to delete a pointer which is not a valid head head. it can also happen in these case

int * p = malloc(100);
p+= nSomeValueLessthan100;
free(p);

So try to debug the function. rather than worrying. It will be ok.

If u can Dream... U can do it

Re: Heap Corruption

yaminisridaran6-Aug-07 0:37

yaminisridaran

6-Aug-07 0:37

ok i will try .Thanks

S.Yamini

Re: Heap Corruption

James R. Twine6-Aug-07 1:56

James R. Twine

6-Aug-07 1:56

yaminisridaran wrote:
Image=(unsigned char *)malloc(50000);
Image=Dlg.CaptureImage();
free(Image);

   In the first line, you are allocating memory into the Image pointer.

   In the second line, you are reassigning that pointer to some other value.

   In the third line, you are calling free(...) on the value obtained in the second line, not the value obtained in the first line, so you may be trying to free a invalid pointer.

   Peace!

-=- James
Please rate this message - let me know if I helped or not!<HR>If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
See DeleteFXPFiles

Re: Heap Corruption

yaminisridaran6-Aug-07 1:57

yaminisridaran

6-Aug-07 1:57

Can u give me any solution for this

S.Yamini

Re: Heap Corruption

James R. Twine6-Aug-07 2:07

James R. Twine

6-Aug-07 2:07

yaminisridaran wrote:
Image=(unsigned char *)malloc(50000);
Image=Dlg.CaptureImage();
free(Image);

Yes, if you skip step #2 and the error goes away, you have found the source of the problem. It seems that you are not passing the allocated memory to CaptureImage(...), and since we do not know what is going on inside of that function, there is little other help that we can provide.

Peace!

Binary File

vipin_nvk5-Aug-07 21:22

vipin_nvk

5-Aug-07 21:22

What is a binary file ? How do u read / write into a binary file.

Thanx

Re: Binary File

Nelek5-Aug-07 22:01

Nelek

5-Aug-07 22:01

Take a look in MSDN about CFile

The modus to read/write is spcified during the creation of the object

Greetings.

--------
M.D.V.

If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?

Re: Binary File

cp98765-Aug-07 22:05

cp9876

5-Aug-07 22:05

Text mode treats end line characters differently. Check out the documentation.

Peter
"Until the invention of the computer, the machine gun was the device that enabled humans to make the most mistakes in the smallest amount of time."

Re: Binary File

toxcct5-Aug-07 22:19

toxcct

5-Aug-07 22:19

open it in notepad... if you find it readable, then it's probably a text file.
if it contains "hieroglyphs" or so, then it's a binary file, and you must know the format of how the data have been written in it to read them back

[VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

exe work but dll does not work?

George_George5-Aug-07 20:41

George_George

5-Aug-07 20:41

Hello everyone,

I have written two simple programs (source codes are the same),

1. In an exe, loading a class from another COM component by invoking CoCreateInstance;

2. In a COM DLL, loading a class from another COM component by invoking CoCreateInstance;

1 success but 2 fails. I am running in the same environment (machine) using Visual Studio 2005. Any ideas of this issue?

thanks in advance,
George

WideChar to Variant conversion

Suneet.035-Aug-07 20:29

Suneet.03

5-Aug-07 20:29

Can anyone tell how to convert a widechar string to VARIANT

I have an unsigned char* string , I am converting it to widechar using MultiByteToWideChar.

How to convert it to VARIANT ?

The data is getting lost if i use ColeVariant.

Re: WideChar to Variant conversion

Aamir Butt5-Aug-07 21:09

Aamir Butt

5-Aug-07 21:09

If you paste your code here, that would be more helpful but simply u can do it by setting the vt of variant to VT_BSTR and then create a bstr. Put the string in BSTR by using ::SysAllocString and set that BSTR in the variant.

Something like:
BSTR bstrString = ::SysAllocString(str);
VARIANT var;
var.vt = VT_BSTR;
var.bstrval = bstrString;

Regards,

"Some people believe football is a matter of life and death.
I'm very disappointed with that attitude.
I can assure you it is much, much more important than that. -- Bill Shankly"

Re: WideChar to Variant conversion

Suneet.035-Aug-07 21:41

Suneet.03

5-Aug-07 21:41

I have sumthng like this

VARIANT getData()
{
unsigned char* puc_Data = " SOME TEXT ";

// I am converting the above unsigned char to whar_t* using

MultiByteToWideChar(CP_UTF8,..,puc_Data,len,wchar_t*,len);

// I want to take this wchar string and convert it to VARIANT
// Doing it thru COleVariant

ColeVariant var(wchar string );

// Data is getting lost sumwhere here ...

return var;

Can anyone suggest wat i m doing wrong??

Re: WideChar to Variant conversion

Roger Broomfield6-Aug-07 2:07

Roger Broomfield

6-Aug-07 2:07

Why not just do this and let COleVariant do what it is designed to do?

ColeVariant getData()
{
char* puc_Data = " SOME TEXT ";
ColeVariant var(puc_Data);
return var;
}

OCR example

Maynka5-Aug-07 20:00

Maynka

5-Aug-07 20:00

Hi all,
From where can i found OCR example(converting image into text) in VC++.

Regards

Re: OCR example

Shouvik Das5-Aug-07 21:12

Shouvik Das

5-Aug-07 21:12

Hope this helps you out
http://www.codeproject.com/cpp/OCRwithMODI.asp?df=100&forumid=378728&exp=0&select=2073309[^]

There are only two kinds of people who are really fascinating-people who know absolutely everything, and people who know absolutely nothing.
Oscar Wilde (1854-1900)
Regards...
Shouvik

Re: OCR example

ThatsAlok6-Aug-07 1:43

ThatsAlok

6-Aug-07 1:43

Maynka wrote:
From where can i found OCR example(converting image into text) in VC++.

it wholly depend on hardware you are using!..

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief

how do switching to ring0

zon_cpp5-Aug-07 19:55

zon_cpp

5-Aug-07 19:55

hi!
how do i switch to ring0 in my program, and i call sidt (asm instruction) for read and change an intrrupt address?

Zo.Naderi-Iran

Re: how do switching to ring0

henky@online-resource.org5-Aug-07 23:27

henky@online-resource.org

5-Aug-07 23:27

Ring0 is in kernel memory area. So, you must create your program
as part of kernel.
(I never create this such program, but as long as i know you must
create modularized program which is registered in OS). D'Oh! | :doh:

Henky Purnawan
henky@online-resource.org

CListCtrl is not display the information in 64-bit windows OS

ksrameshkanth5-Aug-07 18:58

ksrameshkanth

5-Aug-07 18:58

Hi,
I am customizing list control and building with x64 configuration, then testing on 64 bit windows xp professional edition listing of item is missing( Just blank). If any one come across this problem, can help me?

Re: CListCtrl is not display the information in 64-bit windows OS

prasad_som5-Aug-07 20:12

prasad_som

5-Aug-07 20:12

Debugging the code, you can find problem yourself. As we are not aware of code you are using.

Prasad
MS MVP - VC++

const keyword

lavanya815-Aug-07 18:48

lavanya81

5-Aug-07 18:48

Hi,
I am new to this forum>plz let me know which forum is suitable for 'C' language.
And my question is -
What are the possible ways of writing C codes using 'const' keyword. I have written some.I need few more.
Plz go thru and send me any other cases where we can use const keyword in C only not C++.Hope I will get reply as early possible.

const int degrees = 360;
int const degrees1 = 180;

const float pi = 3.14;
const char quit = 'q';

int * const var1;
const int * var2;
int const * var3

const char * const Var4;
char const * const Var5;

void test1() const;
const int * test2(); /* function returns a adress that
could not be modified */

void test3(const int *i);
const int arr1[]={1,2,3,4,5,6,7};

char const *arr="coderzone";
typedef struct member
{
char name[20];
long phno;
};
const struct member M1 = {"Marino" , 62627000};
struct member * const M2 = {"John" , 2786900};
const struct member * const M3 = {"Smith",57361777};

union single
{
int I1;
char C1;
};
const union single S1 = {97};
union single * const S2 = {'A'};
const union single * const S3 = {'0'};

Thank U..

Re: const keyword

Shouvik Das5-Aug-07 19:52

Shouvik Das

5-Aug-07 19:52

There is nothing better than a paper and ink bounded book to learn C or in that case any programming language. To start with C please use the The C Programming Language by Schaum Series and move onto The C Programming Language by Dennis Richie and Brian W Kerningham, Pearson Education Publication.

But if you still insist on online Sites, best would be to Google the keyword and choose the best site upto your understanding.

There are only two kinds of people who are really fascinating-people who know absolutely everything, and people who know absolutely nothing.
Oscar Wilde (1854-1900)
Regards...
Shouvik

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