return __compare_and_swap ((long int *)lock, 0, 1) ? 0 : EBUSY;
return 0;
weak_alias (__pthread_spin_lock, pthread_spin_lock)int__pthread_spin_trylock (pthread_spinlock_t *lock){  return __compare_and_swap ((long int *)lock, 0, 1) ? 0 : EBUSY;}