A valid mq_attr structure is defined. A valid mq_close function is defined. A valid mq_getattr function is defined. A valid mq_notify function is defined. A valid mq_open function is defined. A valid mq_receive function is defined. A valid mq_send function is defined. A valid mq_setattr function is defined. A valid mq_timedreceive function is defined. A valid mq_timedsend function is defined.