extern int _wapi_shm_sem_lock (int sem);
extern int _wapi_shm_sem_trylock (int sem);
extern int _wapi_shm_sem_unlock (int sem);
extern int _wapi_shm_sem_lock (int sem);
extern int _wapi_shm_sem_trylock (int sem);
extern int _wapi_shm_sem_unlock (int sem);