OpenVMS Programming Concepts Manual 2

This document, "OpenVMS Programming Concepts Manual, Volume II," dated April 2001, is the second of two volumes. It serves as a comprehensive guide for system and application programmers using OpenVMS Alpha Version 7.3 and OpenVMS VAX Version 7.3, detailing the programming features offered by the operating system.

The manual is structured into three main parts:

1. OpenVMS Programming Interfaces: Calling a System Routine: This part covers the documentation format for system routine calls, fundamental calling standard conventions (register usage, stack usage, argument lists, and passing mechanisms), and specific instructions for calling Run-Time Library (RTL) routines and system services. It also includes STARLET structures and definitions for C programmers.
2. I/O, System and Programming Routines: This extensive section delves into various aspects of I/O and system programming, including:
   • Run-Time Library Input/Output Operations: Discusses techniques for simple and complex user I/O, utilizing SMG$ routines for screen management, and performing special I/O actions like handling interrupts (Ctrl/C, Ctrl/Y), managing timeouts, and broadcasting messages.
   • System Service Input/Output Operations (QIO): Explains quotas, privileges, and protection, physical/logical/virtual I/O operations, channel assignment and deassignment, synchronizing and canceling I/O requests, device allocation, volume mounting/dismounting, mailboxes, and performance-enhancing features such as Fast I/O and Fast Path (Alpha systems only).
   • Accessing Operating System Components via RTL: Describes how to use RTL routines for system service access, Command Language Interpreter (CLI) functions, VAX machine instructions (e.g., bit field, integer, floating-point, queue, character string routines), process-wide resource allocation, performance measurement, output formatting control, and miscellaneous interfaces like file searching and binary trees.
   • System Time Operations: Details time formats, conversion, date/time manipulation, and timer routines, including Coordinated Universal Time (UTC).
   • File Operations: Covers file attributes, access strategies, protection, mapping files, and handling sequential files and user-open routines.
   • Distributed Transaction Manager: Introduces DECdtm services for managing atomic, distributed transactions.
   • Creating User-Written System Services: Provides guidance on developing privileged routines and shareable images, including the creation of Privileged Library Vectors (PLVs) for both VAX and Alpha architectures.
   • System Security Services: Explains the OpenVMS protection scheme, identifiers, rights databases, Access Control Lists (ACLs), persona and per-thread security (Alpha only), security auditing, and implementing site-specific security policies.
   • Logical Name and Logical Name Tables: Discusses their creation, usage, equivalence names, search lists, access modes, translation, attributes, quotas, and interprocess communication.
   • Image Initialization: Describes the process of image initialization, argument lists, and initialization routines.
3. Appendixes: This part provides supplementary information on generic macros for calling system services, OpenVMS data types, and the Distributed Name Service (DECdns) for VAX systems.

The manual frequently highlights differences and specific requirements between VAX and Alpha architectures for various programming concepts and services.