DIBOL-83

This document is the DIBOL-83 Language Reference Manual, published by Digital Equipment Corporation in October 1983 (with a first printing in May 1983 and an update in October 1983).

It serves as a comprehensive reference for all aspects of the Standard DIBOL-83 programming language, designed for both new and experienced DIBOL programmers. It explicitly states that it does not include information on specific operating systems or their effects on DIBOL-83.

The manual is organized into five main chapters, along with an appendix, glossary, and index:

• Chapter 1: DIBOL-83 Language Elements – Covers the character set, statement types (compiler directives, declarations, data specification, data manipulation, control, intertask communications, input/output), program structure, statement line syntax, labels, array subscripting, literals, and decimal expressions.
• Chapter 2: Data Division – Describes statements for defining data in memory (RECORD, COMMON) and external subroutines (SUBROUTINE), including field and array definitions.
• Chapter 3: The DIBOL-83 Procedure Division Statements – Details a wide array of executable statements for value assignment, data conversion and formatting, I/O operations (e.g., ACCEPT, DISPLAY, READ, WRITE, OPEN, CLOSE, DELETE, STORE), program control (e.g., IF, FOR, GOTO, CALL, RETURN, BEGIN-END, DO-UNTIL, WHILE, USING), and intertask communication (SEND, RECV).
• Chapter 4: The DIBOL-83 Compiler Directives – Explains instructions for the compiler, such as conditional compilation (.IFDEF-.ENDC, .IFNDEF-.ENDC), file inclusion (.INCLUDE), and listing control (.LIST, .NOLIST, .PAGE, .TITLE).
• Chapter 5: Universal External Subroutines – Provides information on various utility subroutines for tasks including ASCII conversion, date/time retrieval, file management (DELET, RENAM), process control (RUNJB, SLEEP, WAIT), and system information (ERROR, FATAL, FLAGS, INSTR, JBNO, MONEY, PAK, RSTAT, SIZE, TNMBR, TTSTS, UNPAK, VERSN).

Each language element, statement, or subroutine is detailed with its function, format, rules, compiler/run-time error conditions, and examples. The appendix lists the DIBOL-83 Character Set, and a glossary defines key terms used in the manual.