Printable View
I have a function that accepts a variable argument list. I would like to extend this function by adding a new argument to the beginning and then calling the original function but I am having trouble with the declaration. Can anyone help?
extern int OriginalFunction( int A, ... );
int NewFunction( char *psz, int A, ... )
{
// call original function
OriginalFunction( A, ??? );
}
how could someone else fill the ... for you???
No I don't have access to the original code and I wouldn't want to break it. I would like to use the polymorphic abilities of C++.
Is there no way to extend such a function without rewriting it or determining the number of arguments.
I was hoping for a way to extend the functionality by decending from it. Something like:
int NewFunction( char *psz, int A, ... ) : OriginalFunction( ??? )
inheritance doesn't work like that....
to do that you would need to encapsulate your function in a class and make it virtual. Then inherit another class from that one and override the virtual function. This would still require you to rewrite the function or do some additional processing and then call the base class version.