kern_setrlimit
return (kern_setrlimit(td, which, &bsd_rlim));
kern_setrlimit(curthread, RLIMIT_STACK, &rlim_stack);
error = kern_setrlimit(td, uap->which, &lim);
error = kern_setrlimit(td, uap->which, &alim);
int kern_setrlimit(struct thread *, u_int, struct rlimit *);