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cassignment-operatorc11aggregate-initializationcompound-literals

Given a pointer to a structure, can I assign the structure the result of an aggregate-initializer in one line?

For example, given a structure S:

typedef struct {
  int a, b;
} S;

... and a method which takes a pointer to S, can I assign it the value of an aggregate initializer1 all in one line? Here's my existing solution which uses a temporary:

void init_s(S* s) {
  S temp = { 1, 2 };
  *s = temp;
}

I'm using C11.

1 For the very rare super-pedant who doesn't understand my question because somehow "aggregate initializer" wouldn't apply here because the LHS is not declaring a new object, I mean "aggregate-initializer-like syntax with the braces and stuff".

Solution

  • Yes, you can using the compound literals syntax:

    #include <stdio.h>

typedef struct {
  int a, b;
} S;

int main(void) {
    S s;
    S *p = &s;

    *p = (S){1,2};

    printf("%d %d\n", p->a, p->b);
    return 0;
}

    Demo