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Override windows function in mixed c and c++ program

I have an application that has both c and c++ files. I have written some functions that I want to over ride some windows functions, namely Registry calls. For example i have a function called my_RegCreateEx and what I want is that when my code calls RegCreateEx I want the call to go to my_RegCreateEx and not the windows default RegCreateEx found in winreg.h.

I have created my_RegCreateEx() function call in a cpp file and used the extern "c" in the my header file, call it my_reg.h. Also in another header file, call it my_functions.h I have a defined as follows:
#define my_RegCreateEx RegCreateEx. Now in any cpp file that I have:
#include "my_functions.h"
#include "my_reg.h"
where I have a call to RegCreateEx() the code will go to my function my_RegCreateEx() as expected but in any C files where I have a RegCreateEx() call it goes to the windows function, which I do not want.

I need help where no matter what type of file, C or C++, the RegCreateEx call will always go to my_RegCreateEx call.

Thanks for you help

Infinity08

Can you show the exact header files you are using ?

Didn't you also mean :

#define RegCreateEx my_RegCreateEx

instead of :

#define my_RegCreateEx RegCreateEx

?

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rendaduiyan

you need to define a new function as RegCreateExA
//include both windows header file and your header file.
#include ....

#ifdef OWN_REGCREATE
#define RegCreateExA my_RegCreateEx
#else
#define RegCreateExA RegCreateEx
#endif

In your codes, call RegCreateExA directly and do not care about which one is called.

Pramod Bugudai

Hi atomicgs12,
this is one general idea that whenever you are using some c language function with some C++ type function you need to define like this:

#ifdef __cplusplus
extern "C"
{
#endif
//C type function
int add(int,int);
int multiply(int,int);
#ifdef __cplusplus
};
#endif