cobol-syntax

name	cobol-syntax
description	COBOL language grammar, division and section structure, PIC clause syntax, level numbers, procedure division verbs, and language construct reference. Use when parsing, analysing, or explaining COBOL source code structure.

COBOL Syntax Reference

COBOL programs are divided into four mandatory divisions in fixed order. See DIVISIONS.md for detailed coverage. Key summary below.

The Four Divisions

1. IDENTIFICATION DIVISION — Program metadata

   • PROGRAM-ID (required), AUTHOR, DATE-WRITTEN, REMARKS

2. ENVIRONMENT DIVISION — System and file linkage

   • CONFIGURATION SECTION: SOURCE-COMPUTER, OBJECT-COMPUTER
   • INPUT-OUTPUT SECTION: FILE-CONTROL with SELECT/ASSIGN pairs

3. DATA DIVISION — All data definitions

   • FILE SECTION: FD entries (file descriptors)
   • WORKING-STORAGE SECTION: in-memory variables and records
   • LINKAGE SECTION: parameters from calling programs
   • LOCAL-STORAGE SECTION: thread-local data (CICS/modern COBOL)

4. PROCEDURE DIVISION — Executable logic

   • Organized into sections and paragraphs
   • USING clause lists LINKAGE SECTION parameters

Level Numbers

Level	Meaning
01	Top-level group item or record
02-49	Subordinate group or elementary items
66	RENAMES clause (aliases)
77	Standalone elementary item (no group)
88	Condition name (boolean flag for a parent item's value)

PIC Clause Quick Reference

Symbol	Meaning	Example
9	Numeric digit	PIC 9(8) = 8-digit number
X	Alphanumeric character	PIC X(40) = 40-char string
A	Alphabetic only	PIC A(10)
V	Implied decimal point	PIC 9(5)V99 = 99999.99
S	Signed number	PIC S9(7)V99
Z	Zero-suppress leading zeros	PIC ZZZ9
$	Currency sign (display)	PIC $$$9.99

Key Procedure Division Verbs

• PERFORM — Call a paragraph (structured GOTO equivalent)

  • PERFORM para-name — single call
  • PERFORM para-name THRU end-para — range
  • PERFORM para-name UNTIL condition — loop
  • PERFORM para-name VARYING x FROM 1 BY 1 UNTIL x > 10 — counted loop

• CALL — Invoke external COBOL program

  • CALL 'PROGRAM-NAME' USING param1, param2
  • CALL 'PROGRAM-NAME' USING BY REFERENCE param (pass by ref)
  • CALL 'PROGRAM-NAME' USING BY CONTENT param (pass by value)

• COPY — Include a copybook

  • COPY copybook-name — verbatim include
  • COPY copybook-name REPLACING ==OLD== BY ==NEW== — with substitution

• MOVE — Data assignment

  • MOVE value TO target
  • MOVE CORRESPONDING source TO target — field-name matching

• EVALUATE — Switch/case

  • EVALUATE TRUE WHEN condition1 ... WHEN condition2 ...
  • EVALUATE variable WHEN value1 ... WHEN OTHER ...

• READ/WRITE/OPEN/CLOSE/REWRITE/DELETE — File I/O verbs

• GOTO — Unconditional branch (legacy, avoid in modern COBOL)

• ALTER — Modifies a GOTO target at runtime (self-modifying, critical risk)

For more detail:

• Division deep dive: read DIVISIONS.md
• Data type details: read DATA-TYPES.md
• All procedure verbs: read VERBS.md