Question

I have a function:

*Foo* create_foo();

where Foo is a struct with many fields:

typedef struct foo {
    int progr_num;
    char* size;
    char* account;
    int matric_num;
    int codex_grp;
    char* note;
} Foo;

What is the exactly return value of this function when I call it??

the function:

Foo create_foo() {
    Foo x;
    ...
    ...
    return x
}

I know that the return type is Foo, but if I invoke the function and want to test the return value, which is the correct value?? (for example if a funcion is an int type, the return is 0 or -1).

When I call the function what is the return correct value??

for example:

int main() {
    Foo foo_check;
    foo_check = create_foo();
    if(!foo_check)
    return ... **???**
}

Answer 1

Rather than passing the (large) struct back and forth on the stack, pass a pointer and use the stack for a status indicator.

struct foo { /* ... whatever ... */ };
int fxfoo(struct foo *pfoo) { /* ... whatever ... */ return ALLOK?0:1; }
int main(void) {
    struct foo objfoo;
    if (fxfoo(&objfoo)) /* error */;
}