Chapter 18: COPY, REPLACE, and Copybook Management -- Further Reading

Books

"Murach's Mainframe COBOL" by Mike Murach and Associates The chapter on copybooks in Murach's text provides an especially practical treatment of how COPY and REPLACING are used in real mainframe shops. The discussion of copybook library organization, naming standards, and the impact of copybook changes on production systems reflects genuine enterprise experience. The paired examples showing a copybook and the programs that consume it are among the clearest available. Available from the Murach website and major technical booksellers.

"Enterprise COBOL for z/OS: A First Course" by Robert C. Cain Cain's textbook includes a thorough chapter on copybook management that covers not only the syntax of COPY and REPLACING but also the organizational practices surrounding copybook governance in large shops. The exercises require readers to create copybooks, share them across multiple programs, and use REPLACING to customize prefixes, which builds practical fluency. Search for this title through university bookstores or technical publishers.

"Advanced COBOL for Structured and Object-Oriented Programming" by Gary DeWard Brown Brown's advanced text treats copybooks as a design tool, exploring how to architect copybook hierarchies that support multiple applications without creating maintenance nightmares. The discussion of nested COPY, version management, and the relationship between copybooks and DCLGEN output is particularly valuable for enterprise developers. Available through major online booksellers.

Online Resources

IBM Enterprise COBOL Language Reference -- COPY Statement The definitive syntax reference for the COPY statement, REPLACING phrase, and pseudo-text delimiters in Enterprise COBOL for z/OS. The syntax diagrams cover every permissible form, including the OF/IN library-name clause and the rules for partial-word replacement. Search for "Enterprise COBOL Language Reference" on the IBM Documentation website and navigate to the Compiler-Directing Statements section.

IBM Enterprise COBOL Programming Guide -- Using Copy Libraries The programming guide provides practical guidance on organizing copybook libraries, setting up the SYSLIB concatenation, and troubleshooting COPY-related compilation errors. It also documents the compiler listing sections that show expanded copybook text, which is essential for debugging REPLACING issues. Find this in the IBM Documentation portal under the Enterprise COBOL Programming Guide.

GnuCOBOL Programmer's Guide -- COPY and REPLACE For open-source COBOL developers, the GnuCOBOL documentation covers how COPY maps to file-system directories, how the -I compiler flag specifies copybook search paths, and any behavioral differences from IBM Enterprise COBOL. The guide includes practical examples of REPLACING with pseudo-text delimiters. Available through the GnuCOBOL project documentation on SourceForge.

IBM Documentation

IBM Redbook: "Batch Modernization on z/OS" This Redbook discusses copybook management in the context of modernizing batch COBOL applications. It covers strategies for consolidating duplicate copybooks, implementing version control for shared data layouts, and integrating copybook changes into CI/CD pipelines on z/OS. The practical case studies illustrate the real costs of poor copybook governance. Search for this title on the IBM Redbooks website.

"DCLGEN Reference" in IBM Db2 for z/OS Documentation DCLGEN generates COBOL copybooks from DB2 table definitions, making it one of the most important copybook-related tools in mainframe development. This reference explains how DCLGEN output is structured, how to customize the generated layouts, and how to incorporate DCLGEN members into programs using COPY and INCLUDE. Available in the IBM Db2 for z/OS documentation library.

Standards and Specifications

ISO/IEC 1989:2023 -- COBOL Standard, Compiler-Directing Statements The current COBOL standard defines the formal specification for the COPY statement, REPLACING phrase, and REPLACE statement. The standard's treatment of pseudo-text matching rules, library-name resolution, and the interaction between COPY and REPLACE is authoritative and resolves ambiguities that implementation-specific documentation may leave open. Available for purchase through ISO or national standards bodies.

"Managing COBOL Copybooks in Enterprise Environments" -- SHARE Conference Proceedings SHARE conference presentations frequently address copybook management challenges in large z/OS installations. Papers on this topic cover governance models, automated impact analysis tooling, and strategies for migrating copybooks when data layouts change. SHARE proceedings are available through the SHARE association website and provide real-world case studies from major enterprises.

"Source Code Management for z/OS" by IBM Systems Magazine This article series discusses how modern SCM tools like IBM Rational Team Concert, Endevor, and ChangeMan manage copybook libraries alongside program source. The focus on library promotion paths, concurrent development conflicts, and automated recompilation triggers is directly relevant to anyone maintaining shared copybooks. Search for back issues of IBM Systems Magazine or its successor publications.