#include <stdio.h>

struct Dummy
{
    int a, b;
};

void
foo(struct Dummy dummy)
{
    dummy.a = 12;
    dummy.b = 34;
}

void
bar(struct Dummy *dummy)
{
    dummy->a = 12;  // indirect member access
    dummy->b = 34;  // indirect member access
}

int
main(void)
{
    struct Dummy d = { 1, 2 };

    foo(d);
    printf("After 'foo(d)': d.a = %d, d.b = %d\n", d.a, d.b);
    bar(&d);
    printf("After 'foo(d)': d.a = %d, d.b = %d\n", d.a, d.b);
}