OSF DCE Application Development Guide--Introduction and Style Guide

Errors and Messaging
may be using the same message catalog names.
Applications that need to guarantee a unique error number space among all DCE
applications should use a registered component number obtained from OSF. This is the
recommended procedure for applications that have public interfaces that are likely to be
called by other applications.
7.2.1 DCE Errors and DCE Messages
An application that wishes to use the DCE message facilities must organize all of its
message text into a separate file which is compiled by the sams utility to generate a
message catalog. The result of the sams compilation is that a set of DCE-consistent,
application-specific codes for all the messages (not only errors) is generated. Use of the
DCE facilities thus guarantees that application-specific status codes will be disjoint from
those used by DCE for fault and comm status values, and for API calls. The application
can then use exactly the same error handling and reporting strategy for application RPC
calls as for API calls.
Of course, generating the message catalogs is only one aspect of using the DCE
facilities. The DCE routines that access the message catalogs to output the messages
must also be used.
7.2.2 DCE Application Message APIs
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.
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