VAX-VMS Operating System, Version 1.0 SPD 25.1.2

This document describes the VAX/VMS Operating System, Version 1.0, a general-purpose, high-performance operating system designed for VAX-11/780 series systems. It supports multiuser timesharing, batch, and time-critical applications in various languages like BASIC, COBOL, FORTRAN, and assembly.

Key features include:

• Virtual Memory Management: Supports large programs, swapping, paging, and provides memory protection and sharing. Applications can control memory allocation, page protection, and swapping.
• Preemptive Priority Scheduling: CPU time and memory residency are allocated on a preemptive priority basis. Time-critical processes (top 16 priorities) do not compete with lower-priority processes and have their priorities fixed unless altered by a manager.
• Protection and Privilege: Implements system security and privacy through memory access protection (between and within processes using virtual address spaces and four access modes). Shared resources (memory, files, interprocess communication) are protected by User Identification Codes (Owner, Group, System, World) controlling access permissions. System services are controlled by assigned privileges and resource quotas.
• System Reliability and Maintenance: Features automatic machine and software consistency checks, auto-reboot on system failure, automatic power failure shutdown/restart, on-line disk backup/restore, user-mode diagnostics, and on-line error logging.
• Command Language: Offers two command interpreters (MCR, DCL) with English-like commands, logical names, and command procedures for creating new commands. Provides operator commands for managing batch and spool queues, system environment, and users.
• Batch Processing: Supports queued batch jobs and transparent line printer output spooling with operator control over job execution and queue management.
• Program Development Tools: Includes compilers for native mode (MACRO, FORTRAN IV-PLUS) and compatibility mode (BASIC-PLUS-2, ANS-74 COBOL), interactive/batch editors, a symbolic debugger, and a file differences utility.
• Record and File Management Services: Provides device-independent access to various storage types, supporting sequential, relative, and indexed file organizations. Features a robust on-disk structure with named directories, automatic space allocation, bad block detection, and concurrent file access. Supports multivolume magnetic tapes and is compatible with RSX/IAS file structures.
• File Sort Utility: Sorts binary/ASCII files in various formats and organizations, callable from COBOL programs, but lacks merge capability.
• Programmed System Services: Offers services for process/subprocess control, interprocess communication (mailboxes, shared memory, event flags), response control (locking memory, adjusting priority), and exception handling.
• Common Run-Time Procedure Library: A set of general-purpose and language-specific procedures, shared as a global section.
• RSX-11 Application Migration Executive (AME): Facilitates the migration of existing RSX-11 applications to VAX/VMS and cross-system development of RSX-11 tasks on VAX/VMS, with specified limitations.
• Installation and Configuration: Automatically configures the system to hardware I/O, allowing dynamic addition of devices/drivers and operator overrides.
• User Environment Test Package: Verifies the installation and readiness of major hardware and software components.

The document also details supported ANSI, FIPS, and ISO standards, minimum and optional hardware requirements, prerequisite and optional software, training credits, support categories (A, B, C), and update policies.