OpenVMS Command Definition, Librarian, and Message Utilities Manual

This manual provides detailed instructions for programmers and general users on using three specific OpenVMS utilities:

• Command Definition Utility (CDU): Used for creating, deleting, or modifying command definitions in command tables, which the command language interpreter (CLI) uses to parse and evaluate DCL commands. It covers writing command definition files, processing them using the SET COMMAND utility, and using command language routines.
• Librarian Utility (LIBRARIAN): Describes how to create, access, and maintain various types of libraries, including object, macro, help, text, and shareable image libraries. It details library structures, character case handling, and management of library modules.
• Message Utility (MESSAGE): Explains how to create and supplement system messages with custom messages. It covers constructing message source files, compiling them, linking them, and using message pointers to manage message text.

The manual includes formatting conventions, usage summaries for each utility, comprehensive descriptions of command qualifiers and file statements, and examples for practical implementation.