Further Reading: Pointer and Reference Modification

IBM Documentation

  • Enterprise COBOL for z/OS: Language Reference — Section on Reference Modification (SC27-1408). Covers all syntax rules, restrictions, and interactions with other features.

  • Enterprise COBOL for z/OS: Programming Guide — Chapter on String Handling, including STRING, UNSTRING, reference modification, and pointer usage patterns (SC27-1412).

  • z/OS Language Environment Programming Reference — Coverage of pointer interoperability between COBOL, C/C++, and Assembler. Essential reading for inter-language pointer passing.

Textbooks

  • Murach, M. Murach's Mainframe COBOL. Chapter on string handling provides practical examples of reference modification in business contexts.

  • Stern, N., Stern, R., & Ley, J. COBOL for the 21st Century. Coverage of reference modification with comparison to INSPECT, STRING, and UNSTRING.

Standards and Formats

  • ANSI X12 EDI Standards (www.x12.org) — The official reference for EDI segment, element, and sub-element structures. Essential background for understanding the MedClaim EDI parsing examples.

  • ASC X12 837 Professional Implementation Guide — Detailed specification for healthcare claim EDI format, including segment definitions and element-level rules.

  • Chapter 17: STRING and UNSTRING — The higher-level string operations that complement reference modification.
  • Chapter 20: Intrinsic Functions — FUNCTION LENGTH, FUNCTION TRIM, and other functions that work naturally with reference modification.
  • Chapter 33: Interfacing with External Systems — Production EDI and data interchange processing using the parsing techniques from this chapter.
  • Chapter 35: Inter-Language Communication — Advanced pointer usage for calling C functions and Assembler routines from COBOL.