Variable number arguments in a c function

Question

Possible Duplicate:
C/C++: Passing variable number of arguments around

How can I do a function that has a variable number of arguments. For example:

      typedef enum{
              Circle, /* has an int argument (int colour)*/
              Square /* has a char argument (char name)*/
      }things;

      /* if arg is a ball I want an int (with colour) argument in f*/
      /* if arg is a square I want a char (with name) argument in f*/
      void f (things arg, ...){
      }

Is this possible to do in the same function f? Thanks

Have you checked this:- http://stackoverflow.com/questions/205529/c-c-passing-variable-number-of-arguments-around ? — Rahul Tripathi, Dec 01 '12 at 08:37
@Zeta That question is about passing variable arguments to another function, not how to get variable arguments in the first place. — Barmar, Dec 01 '12 at 09:15

score 0 · Answer 1 · answered Dec 01 '12 at 08:39

0

Yes. Here is a example of how it is done.

answered Dec 01 '12 at 08:39

Ed Heal

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score 0 · Answer 2 · answered Dec 01 '12 at 08:39

Here is an example it is done, which finds the max of a variable number of numbers.

#include <stdlib.h>
#include <stdarg.h>
#include <stdio.h>

int maxof(int, ...) ;
void f(void);

main(){
        f();
        exit(EXIT SUCCESS);
}

int maxof(int n args, ...){
        register int i;
        int max, a;
        va_list ap;

        va_start(ap, n args);
        max = va_arg(ap, int);
        for(i = 2; i <= n_args; i++) {
                if((a = va_arg(ap, int)) > max)
                        max = a;
        }

        va_end(ap);
        return max;
}

void f(void) {
        int i = 5;
        int j[256];
        j[42] = 24;
        printf("%d\n",maxof(3, i, j[42], 0));
}

Variable number arguments in a c function

2 Answers2