+ switch (protocol) {
+ case PTHREAD_PRIO_NONE:
+ a->__attr &= ~8;
+ return 0;
+ case PTHREAD_PRIO_INHERIT:
+ pthread_once(&check_pi_once, check_pi);
+ if (check_pi_result) return check_pi_result;
+ a->__attr |= 8;
+ return 0;
+ case PTHREAD_PRIO_PROTECT:
+ return ENOTSUP;
+ default:
+ return EINVAL;
+ }