319 #define ENSURE_OPEN(iwkv_) \  argument
320   if (!(iwkv_) || !((iwkv_)->open)) return IW_ERROR_INVALID_STATE; \
321   if ((iwkv_)->fatalrc) return (iwkv_)->fatalrc
326 #define API_RLOCK(iwkv_, rci_) \  argument
327   ENSURE_OPEN(iwkv_);  \
328   (rci_) = pthread_rwlock_rdlock(&(iwkv_)->rwl); \
337 #define API_WLOCK(iwkv_, rci_) \  argument
338   ENSURE_OPEN(iwkv_);  \
339   (rci_) = pthread_rwlock_wrlock(&(iwkv_)->rwl); \
348 #define API_UNLOCK(iwkv_, rci_, rc_)  \  argument
349   rci_ = pthread_rwlock_unlock(&(iwkv_)->rwl); \