when_to_set
if (variant->when_to_set == BEFORE_REUSEPORT)
if (variant->when_to_set == BEFORE_LISTEN)
if (variant->when_to_set == AFTER_LISTEN)
if (variant->when_to_set == AFTER_ALL_LISTEN) {
int when_to_set;
.when_to_set = BEFORE_REUSEPORT,
.when_to_set = BEFORE_LISTEN,
.when_to_set = AFTER_LISTEN,
.when_to_set = AFTER_ALL_LISTEN,