hi there, im trying to save in a private member of my class, a pointer to a ordinary or global function (not a member/method one), so i can call is when certain events happen. for example: class Test { private: int number; void * ptr_to_func; //can i use void? this is the pointer to a global function public: Test() { this->number = 0; this->ptr_to_func = 0; } void set_callback( void (*callback)() ) //this is where i set the global func { this->ptr_to_func = &callback //store the adress } void add( int number ) //just a test method { this->number += number; if( this->number == 10 && this->ptr_to_func ) //is number == 10 and is the ptr_to_func valid? { this->callback(); //this should call the global function, instead it gives me a error C2064: term does not evaluate to a function taking 0 arguments } } }; void print() //our global function { std::cout << "the number is now 10!" << std::endl; } int main( int argc, char *argv[] ) //main function and setup { Test t; t.set_callback( print); //sets print as a callback function for( int i = 0; i < 10; i++ ) t.add( 1 ); //yes 1, not i, so the t.number gets to 10 return 0; }

the function name is the address. So you just store

this->ptr_to_func = callback

The other way you had it was a void **

Here is a quick sample application on how to accomplish what you want..



output:
I'm a useless function!

hth
moe.ron

it works now, guess i cant have a "void * func" as a pointer to a function but only a "void (*func)()"

thanks a lot :)

Quote:Original post by a2ps

it works now, guess i cant have a "void * func" as a pointer to a function but only a "void (*func)()"

thanks a lot :)

You guessed right. void * func is a pointer to a non-typed memory zone. It is not a pointer to a function at all.

Regards,

Quote:Original post by a2ps

it works now, guess i cant have a "void * func" as a pointer to a function but only a "void (*func)()"

thanks a lot :)

I would really suggest just using a typedef like I did. It makes it easier to read and its a lot less typing...