How to return and pass a struct to a function

main.c

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

typedef struct Point {
    double x, y;
} Point;

void getMiddlePoint(const Point* a, const Point* b, Point* out) {
    out->x = (a->x + b->x) / 2;
    out->y = (a->y + b->y) / 2;
}

int main(int argc, char* argv[]) {
    Point p1 = {
        .x = 1,
        .y = 1
    };
    Point p2 = {
        .x = 3,
        .y = 2
    };
    Point middle;
    getMiddlePoint(&p1, &p2, &middle);
    printf("%lf %lf\n", middle.x middle.y);
    
    return 0;
}