Implementing A "Future" (Cont.)

Here is the method to initialize a new future.

/* initialize an int future. gets a pointer to */
/* an allocated but uninitialized struct.      */
/* returns 0 on success, -1 on failure.        */
int int_future_init(struct int_future* f)
{
  int rc = 0;

  if (!f) {
    errno = EINVAL;
    goto int_future_init_ret;
  }