OpenVMS User's Manual
[Digital logo]

OpenVMS User's Manual

Order Number: AA--PV5JC--TK

November 1996

This manual describes how to use the OpenVMS operating system. The information contained in this manual is intended for all OpenVMS users and is applicable to all computers running the OpenVMS operating system.

Revision/Update Information: This manual supersedes the OpenVMS User's Manual, Version 7.0.

Software Version: OpenVMS Alpha Version 7.1 OpenVMS VAX Version 7.1

Digital Equipment Corporation Maynard, Massachusetts

November 1996

Digital Equipment Corporation makes no representations that the use of its products in the manner described in this publication will not infringe on existing or future patent rights, nor do the descriptions contained in this publication imply the granting of licenses to make, use, or sell equipment or software in accordance with the description.

Possession, use, or copying of the software described in this publication is authorized only pursuant to a valid written license from Digital or an authorized sublicensor.

Digital conducts its business in a manner that conserves the environment and protects the safety and health of its employees, customers, and the community.

© Digital Equipment Corporation 1996. All rights reserved.

The following are trademarks of Digital Equipment Corporation: Bookreader, CDA, CDD/Repository, DEC, DEC Ada, DEC C, DECdirect, DECdtm, DEC Fortran, DECnet, DECprint, DECram, DECspell, DECUS, DECwindows, DECwriter, DEQNA, Desktop--VMS, DEUNA, Digital, EDT, GIGI, HSC, LiveLink, LN03, MASSBUSS, MicroVAX, OpenVMS, OpenVMS Cluster, OpenVMS RMS, PrintServer 40, Q-bus, ReGIS, RSX, ULTRIX, UNIBUS, VAX, VAX BASIC, VAXBI, VAXcluster, VAX COBOL, VAX DOCUMENT, VAX FORTRAN, VAX MACRO, VAXserver, VAXstation, VMS, VMScluster, VT, VT100, VT220, VT300, WPS, WPS-PLUS, XUI, and the DIGITAL logo.

The following are third-party trademarks:

Adobe, Adobe Illustrator, Display POSTSCRIPT, and POSTSCRIPT are registered trademarks of Adobe Systems Incorporated.

BASIC is a registered trademark of Trustees of Dartmouth College, D.B.A. Dartmouth College.

Internet is a registered trademark of Internet, Inc.

Microsoft, MS, and MS--DOS are registered trademarks of Microsoft Corporation.

Motif, OSF, OSF/1, OSF/Motif, and Open Software Foundation are registered trademarks of the Open Software Foundation, Inc.

UNIX is a registered trademark in the United States and other countries, licensed exclusively through X/Open Company Ltd.

All other trademarks and registered trademarks are the property of their respective holders.


The OpenVMS documentation set is available on CD-ROM.



Intended Audience

This manual is intended for all users of the OpenVMS operating system.

A system manager performs the administrative tasks that create and maintain an efficient computing environment. If you are a system manager or want to understand system management concepts and procedures, refer to the OpenVMS System Manager's Manual.

Document Structure

This manual contains 19 chapters, 4 appendixes, and a glossary. Each chapter describes concepts and procedures for performing computing tasks. Basic information is presented first within each chapter; more complex concepts and procedures are presented last.

Getting Started

Refer to the following chapters to help you get started using the OpenVMS operating system:

Communicating with Other Users

Refer to the following chapters to learn about communicating with other users:

Manipulating Text and Records

Refer to the following chapters to learn about text processing and record sorting:

Using Devices

Refer to the following chapter to learn about devices:

Logical Names and Symbols

Refer to the following chapters to learn about logical names and symbols:


Refer to the following chapters to learn about writing programs and using programming functions:

Managing Processes

Refer to the following chapter to learn about managing processes:

Ensuring Security

Refer to the following chapter to learn about security:

Reference Sections

The following information is provided for reference:

Related Documents

For more information, refer to the following manuals:

For additional information on the Open Systems Software Group (OSSG) products and services, access the Digital OpenVMS World Wide Web site. Use the following URL: 

Reader's Comments

Digital welcomes your comments on this manual.

Print or edit the online form SYS$HELP:OPENVMSDOC_COMMENTS.TXT and send us your comments by:
Fax 603 881-0120, Attention: OSSG Documentation, ZKO3-4/U08
Mail OSSG Documentation Group, ZKO3-4/U08
110 Spit Brook Rd.
Nashua, NH 03062-2698

How To Order Additional Documentation

Use the following table to order additional documentation or information. If you need help deciding which documentation best meets your needs, call 800-DIGITAL (800-344-4825).


The name of the OpenVMS AXP operating system has been changed to the OpenVMS Alpha operating system. Any references to OpenVMS AXP or AXP are synonymous with OpenVMS Alpha or Alpha.

VMScluster systems are now referred to as OpenVMS Cluster systems. Unless otherwise specified, references to OpenVMS Clusters or clusters in this document are synonymous with VMSclusters.

In this manual, every use of DECwindows and DECwindows Motif refers to DECwindows Motif for OpenVMS software.

The following conventions are also used in this manual:
Ctrl/ x A sequence such as Ctrl/ x indicates that you must hold down the key labeled Ctrl while you press another key or a pointing device button.
PF1 x or
A sequence such as PF1 x or GOLD x indicates that you must first press and release the key labeled PF1 or GOLD and then press and release another key or a pointing device button.

GOLD key sequences can also have a slash (/), dash (--), or underscore (_) as a delimiter in EVE commands.

[Return] In examples, a key name enclosed in a box indicates that you press a key on the keyboard. (In text, a key name is not enclosed in a box.)
... Horizontal ellipsis points in examples indicate one of the following possibilities:
  • Additional optional arguments in a statement have been omitted.
  • The preceding item or items can be repeated one or more times.
  • Additional parameters, values, or other information can be entered.
Vertical ellipsis points indicate the omission of items from a code example or command format; the items are omitted because they are not important to the topic being discussed.
( ) In command format descriptions, parentheses indicate that, if you choose more than one option, you must enclose the choices in parentheses.
[ ] In command format descriptions, brackets indicate optional elements. You can choose one, none, or all of the options. (Brackets are not optional, however, in the syntax of a directory name in an OpenVMS file specification or in the syntax of a substring specification in an assignment statement.)
{ } In command format descriptions, braces indicate a required choice of options; you must choose one of the options listed.
text style This text style represents the introduction of a new term or the name of an argument, an attribute, or a reason.

This style is also used to show user input in Bookreader versions of the manual.

italic text Italic text indicates important information, complete titles of manuals, or variables. Variables include information that varies in system output (Internal error number), in command lines (/PRODUCER= name), and in command parameters in text (where device-name contains up to five alphanumeric characters).
UPPERCASE TEXT Uppercase text indicates a command, the name of a routine, the name of a file, or the abbreviation for a system privilege.
Monospace type Monospace type indicates code examples and interactive screen displays.

In the C programming language, monospace type in text identifies the following elements: keywords, the names of independently compiled external functions and files, syntax summaries, and references to variables or identifiers introduced in an example.

- A hyphen at the end of a command format description, command line, or code line indicates that the command or statement continues on the following line.
numbers All numbers in text are assumed to be decimal unless otherwise noted. Nondecimal radixes---binary, octal, or hexadecimal---are explicitly indicated.

Chapter 1
Introduction: OpenVMS Concepts and Definitions

1.1 Overview

OpenVMS is an interactive virtual memory operating system. While you are logged in to the computer, you and the system conduct a dialogue using the DIGITAL Command Language (DCL). You use DCL by entering commands, which the system reads and translates. You enter a command by typing it from your keyboard and pressing the Return key; the system responds by executing the command or by displaying an error message on the screen if it cannot interpret what you entered.

This chapter describes basic concepts about the OpenVMS operating system and its components. It includes introductory information on the following topics:

1.1.1 Differences in Your Local Environment

Note that this manual covers standard DCL commands only. System managers at your site may tailor your system to support the local environment. A system manager might decide to:

1.1.2 References

Additional information about the commands discussed in this chapter can be obtained from:

1.2 Logging In to the System

Logging in consists of gaining access to the system and identifying yourself as an authorized user. When you log in, the system creates an environment from which you can enter commands. This environment is called your process.

Chapter 2 describes how to log in to and out of the system.

1.2.1 Accounts

To interact with the operating system, you must log in to a user account. An account is a name or number that identifies you to the system when you log in. That name or number tells the system where your files are stored and the type of access you have to other files.

Your system manager (or whoever authorizes system use at your installation) usually sets up accounts and grants privileges according to your needs. The type of access rights and privileges enabled for your account determine whether you have access to files, images, or utilities that might affect system performance or other users.

1.2.2 Access Requirements

To access your account, you need to enter your user name and password. Your system manager usually provides you with your user name and initial password. Your user name identifies you to the system and distinguishes you from other users. In many cases, a user name is your first or last name. Your password is for your protection. If you maintain its secrecy, other users cannot use system resources under your user name.

1.3 Networks

When computer systems are linked together, they form a network. Operating systems in a DECnet for OpenVMS network are able to communicate with each other and share information and resources. Each system in a network is called a network node and is identified by a unique node name.

1.3.1 Network Nodes

When you are logged in to a network node, you can communicate with other nodes in the network. The node at which you are logged in is called the local node; other nodes on the network are called remote nodes. If you have access to an account on a remote node, you can log in to that account from your local node and perform tasks on that node while remaining connected to your local node.

Chapter 2 describes how to log in to a remote node. Additional tasks you can perform on remote nodes are described in the appropriate chapters of this manual.

1.3.2 Executing Programs Over Networks

Because of support provided by DECnet software, programs can execute across the network as if they were executing locally. Because DECnet software is integrated within the operating system, it is easy to write programs that access remote files. To access a remote file in an application program, you need only include the name of the remote node and any required access control information in the file specification.

1.3.3 Task-to-Task Communication

Task-to-task communications, a feature common to all DECnet implementations, allows two application programs running on the same or different operating systems to communicate with each other regardless of the programming languages used. Examples of network applications are distributed processing applications, transaction processing applications, and applications providing connection to servers.

1.3.4 Proxy Acounts

In the examples of remote operations in this manual, proxy accounts enable users to perform operations on remote systems. Proxy accounts are one way users can access remote systems. For additional ways to access remote systems, see the OpenVMS System Manager's Manual.

1.4 DIGITAL Command Language (DCL)

DCL (DIGITAL Command Language) is a set of English-like instructions that tell the operating system to perform specific operations. DCL provides you with over 200 commands and functions to use in communicating with the operating system to accomplish computing tasks.

1.4.1 Usage Modes

You can use DCL in the following two modes:

1.4.2 Types of DCL Commands

When you enter a DCL command, it is read and translated by the DCL interpreter. The way the command interpreter responds to a command is determined by the type of command entered. The three types of DCL commands are as follows:

1.4.3 DCL Command Line

DCL, like any language, has its own vocabulary and usage rules. The vocabulary consists of commands, parameters, and qualifiers, which are put together in a way that DCL can interpret. The way in which the parts of a command line are put together is referred to as the command line syntax.

1.4.4 DCL Command Line Format

A DCL command line uses the following format:

[$] command [[/qualifier[=value]]...] [[parameter[=value][/qualifier...]]...] 


Items in brackets [ ] are optional and might not be required by a specific command.

For a complete description of the components of a DCL command line, see Section 3.3.1.

1.4.5 Lexical Functions

Lexical functions are command language constructs that the DCL interpreter evaluates and substitutes before it interprets a command string. Chapter 17 discusses lexical functions in more detail.

1.5 Files and Directories

A file is a system object that contains information. This information can be machine-readable data that the computer understands. It can also be text you enter and manipulate. The text in the file might be the text of a document, a program, or a list of addresses. You can examine the data in these files by displaying the files on a terminal screen or by printing them on paper.

Chapter 4 describes how to create and organize files to store information.

A directory is a special kind of file that contains the names and locations of files; files are listed in directories. For example, when the system manager creates a user account for you (see Section 1.2), you automatically have a directory with the same name as your user name. If your user name is JONES, the directory is [JONES].

Chapter 5 describes how to use directories to organize and manage files.

1.5.1 Hardware

Directory files are stored on disks. Disks are one type of hardware device that the operating system uses to store information.

1.5.2 File Specifications

Every file must have a file name or file type to identify it to both the system and you. A file also has a version number. You can have several versions of a file. Unless you specify a version number, the system uses the highest existing version number of a file. When you edit a file, the system saves the original file and produces a modified output file. By default, the output file has the same name and type as the original but the version number is incremented by one.

The file name, file type, and version number form a file specification. A full file specification:

1.5.3 Directory Structures

Each disk contains a main directory, which can be set up by a system manager or by the system itself. This main directory is called the master file directory (MFD) and contains a list of user file directories (UFDs). UFDs are files in the master file directory that point to top-level directories. Your top-level directory is usually your login or default directory. Unless your account has been modified to do otherwise, the system automatically places you in your top-level directory when you log in.

Next | Contents | [Home] | [Comments] | [Ordering info] | [Help]


  OSSG Documentation
  22-NOV-1996 13:16:30.26

Copyright © Digital Equipment Corporation 1996. All Rights Reserved.