A function returns a structure

[xinwu]

Hi, everyone! Is it safe to let a function return a structure type? For example, which function is better in practice in the example below?

Thanks in advance!

#include <stdio.h>

struct abc {
  int i;
  float f;
};

static struct abc f1 (int, float);
static void f2 (struct abc *, int, float);

struct abc f1 (int i, float f) {
  struct abc a;
  a.i = i;
  a.f = f;
  return a;
}

void f2 (struct abc *a, int i, float f) {
  a->i = i;
  a->f = f;
}

int main (void) {
  int i = 10;
  float f = 12.3;
  struct abc a, b;
  a = f1 (i, f);
  f2 (&b, i, f);
  printf("a: %3d %5.2f\n", a.i, a.f);
  printf("b: %3d %5.2f\n", b.i, b.f);
  return 0;
}

[Bayint Naung]

>> Is it safe to let a function return a structure type?
Yes.
If the size of struct is big, passing by value and returning might be expensive.

[xinwu]

Thanks!
Does it mean that a function that returns a structure ACTUALLY returns the values of its every member?

[quzah]

Yes, just like any other data type. Typically you're better off passing a pointer to the structure you want and just filling it inside the function, or, dynamically allocating the structure inside the function and returning a pointer to it. But yes, you can return an actual structure.


Quzah.