Message generation by distributed programs can be divided into two broad kinds:
· Normal (often user-prompted, client-generated) messages
· Server event messages, containing information about server activity, either normal or extraordinary
Similarly, DCE makes available to applications two messaging APIs:
· The DCE messaging interface
· The DCE serviceability interface
The DCE serviceability interface is designed specifically to output messages of the second (server event) type. Messages in the first category can be output using the DCE general purpose application messaging routines.
Although the two interfaces, broadly speaking, do the same general thing (that is, write messages), their functionality was designed to serve different needs, both of which occur in most distributed applications. Nevertheless, either interface can be used more or less exclusively of the other, if desired. Both interfaces use message catalogs (for the most part) to generate output; the catalogs themselves are generated by sams during compilation, as mentioned earlier.
The following topics describe some aspects of using the serviceability interface. Full discussions of both interfaces can be found in the OSF DCE Application Development Guide - Core Components.