User's Introduction to VAX DEC/CMS

This document serves as an introductory guide to VAX DEC/CMS (Code Management System) Version 2.0, designed for software engineers, technical writers, and managers using VAX/VMS Version 4.0 or later. It explains how CMS facilitates the software development cycle, tracks changes, records user access, and provides mechanisms for organizing project files.

The manual covers fundamental CMS concepts, including:

• Elements: The basic units (ASCII files) stored within a CMS library.
• Generations: Successive versions of an element, each representing a phase in its development.

It details the procedures for:

• Building a CMS Library: Creating and protecting a library directory, initializing it with CMS CREATE LIBRARY, and adding project files as elements using CMS CREATE ELEMENT.
• Accessing and Modifying Files: Commands like CMS SET LIBRARY to gain access, CMS RESERVE to retrieve a file for modification (marking it reserved), CMS UNRESERVE to cancel a reservation, CMS REPLACE to store modified files back into the library (creating a new generation), and CMS FETCH to retrieve read-only copies.
• Obtaining Library Information: Various CMS SHOW commands display lists of elements, current reservations, transaction history, and the evolution of specific element generations (ancestors and descendants).
• Managing Concurrent Development: Strategies for handling alternate development paths using variant lines of descent (/VARIANT qualifier) and merging changes from different paths (/MERGE qualifier), including resolving merge conflicts. It also addresses how CMS manages simultaneous work on the same element by multiple users.
• Project Organization: Utilizing CMS Groups to logically combine related elements and CMS Classes to organize specific element generations by project milestones or releases, ensuring precise control over product versions.
• Additional Utilities: Commands such as CMS ANNOTATE for line-by-line change history and CMS DIFFERENCES for comparing files.

The document highlights CMS's role in maintaining a complete historical record of project modifications, facilitating collaboration, and ensuring the integrity of the software development process. It also briefly discusses library storage methods and backup considerations.