The application creates and destroys the data container. Two methods, INIT and FREE, have been defined in the interface for this purpose.

The method INIT replaces the constructor and must be called by the application explicitly. There are two reasons why a constructor is not used: first, so that all data containers are initially called in the same way and second because INIT sends a return value.

The method FREE replaces the destructor but it must be called by the application explicitly.