/*Passing Structures to Functions by CBR*/

#include <stdio.h>

// define a structure template
struct demo{
	int a;
	char *str;
	int *ptr;
};

//function prototype
void f1(struct demo parm, struct demo *parm_ptr);

int main(void)
{
	int value = 1;
	struct demo arg, *arg_ptr=&arg;

	arg.a = 100;
	arg.str = "hello";
	arg.ptr = &value;

	f1(arg, arg_ptr); //CBV & CBR		

	return 0;
}

void f1(struct demo parm, struct demo *parm_ptr)
{
	printf("%d %d %d %s %s %d %d\n", parm.a, parm_ptr->a, 
(*parm_ptr).a, 
(*parm_ptr).str, parm_ptr->str, *(parm_ptr->ptr), *((*parm_ptr).ptr));
}

/*Note: 
  1. When a pointer to a structure is passed to a function,
     only the address of the structure is pushed on the stack. 
     This makes for very fast function call.
  2. Passing a pointer makes it possible for the function to 
     modify the contents of the structure used as the argument.
*/