How to count the number of arguments passed to a function that accepts a variable number of arguments?

Question

How to count the no of arguments passed to the function in following program:

#include
#include
void varfun(int i, ...);
int m         


        

Answer 1

If you have a C99 compliant compiler (including the preprocessor) you can circumvent this problem by declaring a macro that computes the number of arguments for you. Doing this yourself is a bit tricky, you may use P99_VA_ARGS from the P99 macro package to achieve this.