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C++ object method called from C

Posted on 1998-12-10
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Last Modified: 2010-04-02
I have to mix up C library functions and C++ objects.
At some point I wish that a C function calls a C++ method.

The problem is that the C functions is called from a .c compiled file.

This is an example of the cf function called from a function defined in a .c file.
cf( void* p ){
   ((Class*)p)->method();
}

Apparently it is possible to call C functions from C++ but not the reverse.

Any help would be warmly welcomed.
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Question by:meessen
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3 Comments
 
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stsanz earned 800 total points
ID: 1179818
Try defining an exported C function in your C++ files to wrap up the object method, so you can call C from C.

Declare this wrapper function as :
extern "C" MyWrapperFunction (...)
{ ... }


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Author Comment

by:meessen
ID: 1179819
Ok. Just found out my self in the same time.
You gave the right answer.

I thought that using extern "C" would disallow to use method calls from within the encapsulated function. But apparently not. My test work.

Enjoy the points and the grade ;-)

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Expert Comment

by:stsanz
ID: 1179820
extern "C" only defines how external parameters and return values are passed through, and how exported functions are named (the latter is different between C and C++)

Nevertheless, your extern "C" function is still C++ because it is defined in a CPP file.


 
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