program17-2.c

// Copiling in Debug Code

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

int process(int i1, int i2)
{
    int val;

#ifdef DEBUG 
    fprintf(stderr, "process(%i, %i)\n", i1, i2);
#endif

    val = i1 * i2;

#ifdef DEBUG
    fprintf(stderr, "return %i\n", val);
#endif

    return val;
}


int main(int argc, char *argv[])
{
    int arg1 = 0, arg2 = 0;

  if (argc > 1)
      arg1 = atoi(argv[1]);
    if (argc == 3)
        arg2 = atoi(argv[2]);

#ifdef DEBUG
      fprintf(stderr, "processed %i arguments\n", argc - 1);
      fprintf(stderr, "arg1 = %i, arg2 = %i\n", arg1, arg2);
#endif

    printf("%i\n", process(arg1, arg2));

    return 0;

}