OpenVMS Command Definition, Librarian, and Message Utilities Manual

This manual describes three utility tools for the OpenVMS operating system:

• Command Definition Utility (CDU): Explains how to use CDU to create, modify, or delete command definitions in command tables. It covers writing command definition files (using statements like DEFINE VERB, DEFINE SYNTAX, and DEFINE TYPE), processing these files using the DCL SET COMMAND command, and using command language routines in programs.
• Librarian Utility (LIBRARIAN): Details how to create and maintain various types of libraries (object, macro, help, text, and shareable image). It explains library structure, how to use qualifiers for library management (such as /CREATE, /INSERT, /EXTRACT, and /COMPRESS), and how to manage help files and modules.
• Message Utility (MESSAGE): Describes how to supplement OpenVMS system messages with custom messages. It covers constructing message source files using directives (like .FACILITY, .SEVERITY, and .IDENT), compiling and linking message object modules, using message pointers for flexible message management, and using the SET MESSAGE command.