DIBOL-83

This document is the DIBOL-83 Compatibility Guide, published in May 1983, with Order No: AA-V810A-TK.

Its primary purpose is to help developers create transportable DIBOL applications by detailing the specific differences in how DIBOL-83 statements and Universal External Subroutines function across various Digital Equipment Corporation (DEC) operating systems. It is intended to be used alongside the DIBOL Language Reference Manual and relevant DIBOL system user guides.

The guide applies to the following DIBOL-83 implementations:

• CTS-300 V8.0
• RSTS/E DIBOL V5.0
• VAX/VMS DIBOL V2.0
• Professional Tool Kit DIBOL V1.5

The document covers compatibility considerations in these key areas:

1. Compiler Directives: Differences in how compiler options behave.
2. Language Elements: Variations in character sets, statement syntax, labels, array subscripting, literals, substrings, and decimal expressions.
3. Data Division Statements: Specific behaviors of RECORD, COMMON, Field Definitions, Array Definitions, and SUBROUTINE statements.
4. Procedure Division Statements: Details on the functionality and any system-specific nuances of numerous DIBOL commands (e.g., ACCEPT, OPEN, READ, WRITE, SEND, STOP, XCALL).
5. Universal External Subroutine Library: Explanations of how various subroutines (e.g., ASCII, DATE, FLAGS, RUNJB, PAK, UNPAK) operate across different systems.
6. File Migration: Comprehensive procedures for transferring DIBOL source and data files between systems using either DECnet or transfer media (disks, diskettes, magtape), including necessary steps for file format conversion.