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Document:	VAX/VMS Primer
Order Number:	AA-D030C-TE
Revision:	0
Pages:	102
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VAX/VMS
Primer
Order No. AA-DO30C-TE

VAX/VMS
Primer

Order No. AA-DO30C-TE

May 1982

This tutorial document introduces the DIGITAL Command Language, the EDT editor,
file manipulation, program development, and basic operating system concepts.

REVISION/UPDATE INFORMATION: This revised document supersedes the
VAX/VMS Primer (Order No. AA-DO30B-TE).

SOFTWARE VERSION:

VAX/VMS Version 3.0

digital equipment corporation - maynard, massachusetts

First Printing, August 1978
Revised, March 1980
Revised, May 1982

The information in this document is subject to change without notice and should not be con-

strued as a commitment by Digital Equipment Corporation. Digital Equipment Corporation
assumes no responsibility for any errors that may appear in this document.

The software described in this document is furnished under a license and may be used or copied
only in accordance with the terms of such license.

No responsibility is assumed for the use or reliability of software on equipment that is not
supplied by Digital Equipment Corporation or its affiliated companies.

Printed in U.S.A. |
A postpaid READER’S COMMENTS form is included on the last page of this document. Your
comments will assist us in preparing future documentation.
The following are trademarks of Digital Equipment Corporation:
DEC

DIBOL

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Edusystem

UNIBUS

TAS

VAX

DECsystem-10

MASSBUS

VMS

DECSYSTEM-20

PDP

DECUS

PDT

mflaflnan

DECwriter

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DEC/CMS
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Internal orders should be placed through the Software Distribution Center (SDC), Digital Equipment

Corporation, Northboro, Massachusetts 01532

10/82-14

Contents

Preface

Chapter 1

Accessing the System and Typing Commands
1.1

Terminals.

1.2

Keyboards.

1.3

LoggingIn.

Gaining Access to the System .

1.3.2
1.4

1.4.2
1.4.3

1.8

Chapter 2

...

.
. .
. .

. .
Command Prompting.
Abbreviating Commands .
Recovering from Errors . .

.
.

..
. L
. ..

.
.

Defaults . . . . . . . . . ... P I
Information Messages. .
Error Messages. . .. .

1.5.2
1.5.3
1.7

. .

System Responses . . . . . . . . o000 e

1.5.1
1.6

. ..

. .

Entering Commands.
1.4.1

1.5

. . . . . . . . . .

Getting the Terminal Ready.

1.3.1

000

00000

..o

.
.

. .

.
.

. . .
...

The HELP Command . . . . . I
.

LoggingOut.

For More Information

... o
. . . . ..

..o

...

Using an Editor: EDT
2.1

2.2

2.3

Files

..o

211

File Names.

2.1.2

FileTypes .

.«

o000

2.1.3

File Versions .

. e

Editors . . . . . . .
Introduction to EDT. .

)

e
.

e
o

...

2.4

2.5

2.6

2.7

241

TheGold Key

2.4.2

The HELP Command.

243

CreatingakFile.

24.4

EditingaPFile

2.4.5
24.6

ScanningaFile.

...

.. 2-3

oo 2-4

.. 2-4

...

.00 26

Manipulating the Cursor

2.4.7

Changing the Cursor’s Direction.

. .

2.4.8

Deleting and Restoring Text.

2.4.9

Locating Text

2.4.10

Moving Text .

2.4.11

Entering Line Comands in Keypad Mode

...

o000 2-4

... P 2-6

..o

L0 2-17

.. 2-8

.. 2-9

...

2-10

2-11

. - 2-13

2.4.12

Changing From Keypad to Line Editing . .

2-13

2.4.13

Subset of EDT Keypad-Editing Commands

. .

2-13

Line Editing in EDT.

2.56.1

The HELP Command.

252

CreatingalkFile.

2.56.3

EditingaPFile

...

2-14

...

2-15

...

2-15

..o

2-16

2.5.4

Specifying Ranges

... e

2-16

2.56.5

Inserting and Deleting Text .

2-17

2.5.6

Locating Text

2.5.7

Substituting Text.

2.5.8

Copying and Moving Text.

...

... ..

2-18

...

2-18

2.56.9

Changing from Line to Keypad Editing

2-18

2.5.10

Subset of EDT Line-Editing Commands .

2-19

...

Special Features of EDT .

2.6.1

Multiple Buffers

2.6.2

dJournal Files .

...

2-19

...

2.6.3

2-19

SET and SHOW Commands

. .

...

2-20

2.6.4

Start-up Command Files .

. .

.. L.

2220

2.6.,5

Defining Keys

..o

2.6.6

Defining Macros

...

... o 3-1
e

e, 3-1

e ' 3-2

For More Information

2-17

oo - 2-20

...

2-20
2-21

Commands to Manipulate Files
3.1

Identifying Files .

3.1.1

Nodes

3.1.2

Devices

3.1.3

Directories and Subdirectories.

. e 3-2

3.1.4

File Names, Types, and Versions

3.1.5

Wild Card Characters.

.. e e

Chapter 3

Keypad Editing in EDT .

.. e

.. 3-3

e 3-4

.o 3-5

3.2

Creating Files .

3.3

Deleting Files .

..., 3-5

3.4

Purging Files

...

3.5

Displaying Files at Your Terminal

3.6

Printing Files

3.7

Listing Files in a Directory.

3.8

Creating Subdirectories

... e
.

e 3-6

... 3-6

. P 37

... 3-8

...

.. 3-7

3.9

Changing Your Default Directory . . . . . . . . . . . . . . . . . . ..

3.10 Copying Files . . . . . . . . . . oo 3-9
e 3-10
3.11 Renaming Files . . . . . . . . . . . oo
.. 310
..
...
o
.
.
.
.
.
.
.
.
.
.
.
.
Information
More
3.12 For

Chapter 4

Program Development

4.1
4.2
4.3
4.4
45

Creating the Program . . . . . . . e 4-1
Compiling or Assembling the Program . . . . . . . . . . . . . .. .. 4-2
e e 4-3
e e
Linking the Object Module. . . . . . e
4-3
e
e
..
.
.
.
.
.
.
.
.
.
.
.
.
.
Executing the Program.
4-5
e
e
e
v
v
v
v
v
v
v
v
o
«
«
«
.
.
.
.
.
.
.
A FORTRAN Program
4-5
e e e e
4.5.1 Creating the Source Program . . . . . e
4-6
..
.
.
.«
.
.
.
.
.
.
.
.
.
.
.
.
452 The FORTRAN Command
4-8
e
..
.
.
.
.
.
.
.
Module
4.5.3 Linking the Object
4-8
o0
.
.
.
.
.
.
.
.
.
.
.
.
.
4.5.4 Running the Program.
4-9
...
.
.
.
.
.
.
.
.
.
.
.
.
.
.
Program
the
4.5.5 Debugging
e e e e 4-10
A MACRO Program . . . . . . . . . . .. e
4.6.1
46.2
4.6.3
4.6.4
4.6.5

4.7
Chapter 5

Creating the Source Program
The MACRO Command . .
Linking the Object Module .
Running the Program. . . .
Debugging the Program . . .

.
.
.
.
.

For More Information . . . . . . . . . .

.
.
.
.
.

o .

.
.
.
.
.

.
«
.
.
.

. . . ...
« .« .« ..
. . . ...
. ...
. ...

4-11
4-12
4-13
4-13
4-14

oo e .. 4-15

Logical Names: Files for Prbgram Input/Output
5.1

5.2
5.3

5.4
5.5

Logical Names in Commands. . . . . . . . . e e 5-2

System Default Logical Names . . . . . . .
FORTRAN Input/Output. . . . . . . . . .
'5.3.1 Changing Default Logical Names . .
5.3.2 Logical Names for Unit Numbers . .
5.3.3 Logical Names in OPEN Statements

. . . . . .. e 5-3
o o v o 5-4
.«
. . . « v v v o v o v 5—4
. . . . . . . . . . .. .. 5-5
. . . . . . . . . . . . .. 5-6

e e 5-6
MACRO Input/Output. . . . . . . . . . . . . .. e
e 5-7
..
.
.
.
.
.
.
.
.
.
.
.
.
.
.
n
Informatio
For More

Chapter 6 Tailoring the Command Language
6.1
6.2

6.3
6.4
6.5
Glossary

Index

Symbols. . . . . . .o e 6-1
Command Procedures . . . . . . . . . . . .. oo P 6-2
6.2.1 Using Symbols in Command Procedures . . . . . . . . . . . . .63
6.2.2 Redefining System Commands . . . . . . . . . . . . . .« . . 6—-4
6.2.3 A LOGIN.COM File . . . . . . . . . o o v o o v v v v v v v 6-5
Batch Job Processing . . . . . . . . . . o oo e e e e e e 6-6
Programming Command Procedures . . . . . . . . . . . . . . . . 6-6
For More Information . . . . . . . . . « o« o o oo e e e e e 6-7

Tables
1

Sources of Information in VAX-11 Documentation.

2-1

Subset of EDT Keypad-Editing Commands .

. e

2-2

Subset of EDT Line-Editing Range Specifications .

2-3

Subset
of EDT Line-Editing Commands

1-1

The LA120 Terminal.

1-2

The VT100 Terminal.

1-3

The LA120 and VT100 Keyboard Layouts.

2-1

The VT52 and VT100 Keypads .

4-1

Steps in Program Development.

.
.

. viil

2-16

. .

. ..

2-19

.. e

. e

4-2

Commands for FORTRAN Program Development .

4-3

Commands for MACRO Program Development

5-1

Using Logical Names.

Figures

...

e 1-1

.. 1-2

e 1-3

...

.. 4-5

...

.. 2-3

... 4-4

4-10

.. 5-2

Preface

users
A primer is a book for beginners. The VAX/VMS Primer introduces new ence,

to the VAX/VMS operating system. Depending upon your prior experi
c details.

you may want to read this book carefully or just skim it for specifi

.
Between you and the computer 1s VAX/VMS, the operating itssystem
hard-

VAX/VMS allows users to share the resources of the computer and
ware devices, such as disks, tapes, terminals, and printers.

that you
Communication with the operating system consists of commands
that an
nds
sive it and messages that it gives in response. The set of comma
operating system recognizes constitutes its command language.

and lanDIGITAL Command Language, or DCL, is the name of the comm
ives of
guage you use to communicate with VAX/VMS. One of the main object
ge.
this primer is to introduce you to the DIGITAL Command Langua

VMS, its
Eventually, you will need to know more information about VAX/
ns encommand language, and its services than this primer presents. Sectio
these
rs;
chapte
ing
follow
titled “For More Information” conclude each of the
materi
about
ation
sections direct you to further sources of specific inform VAX-11 Informatioaln
discussed in the preceding chapter. In addition, the VMS software docuDirectory and Index provides a guide to the entire VAX/ ion organized by
ment set. See Table 1 for a list of VAX-11 documentat
subject.

vIL

Table 1: Sources of Inforniation in VAX-11 Documentation
For information on:

VAX/VMS Documentation
VAX/VMS Installation,

Management, and Operations:

Look in these manuals:

{

VAX-11 Information Directory and Index
VAX/VMS Release Notes
VAX-11/780 Software Installation Guide
VAX-11/750 Software Installation Guide
VAX-11/730 Software Installation Guide

VAX-11/782 User’s Guide

VAX/VMS System Management and Operations Guide
VAX/VMS UETP User’s Guide
DIGITAL Command Language

Program Development,
Testing, and Control

VAX/VMS Command Language User’s Guide
VAX/VMS Guide to Using Command Procedures
VAX-11 SOS Text Editing Reference Manual
EDT Editor Manual

VAX/VMS DIGITAL Standard Runoff User’s Guide
VAX/VMS Magnetic Tape User’s Guide
VAX-11 Linker Reference Manual

VAX-11 Symbolic Debugger Reference Manual

(

VAX/VMS Real-Time User’s Guide

VAX/VMS Guide to Writing a Device Driver
VAX/VMS System Messages and Recovery Procedures
Manual

File and Record Management

Introduction to VAX-11 Record Management

Services
VAX-11 Record Management Services Reference

Manual
|
VAX-11 Record Management Services Utilities
Reference Manual
VAX-11 Record Management Services Tuning Guide
Programming Utilities and
Development Tools

VAX-11 Utilities Reference Manual

VAX-11 PATCH Utility Reference Manual

VAX-11 SORT/MERGE User’s Guide

VAX/VMS System Services Reference Manual
VAX/VMS I/O User’s Guide
VAX-11 Run-Time Library User’s Guide

VAX-11 Run-Time Library Reference Manual
VAX/VMS System Dump Analyzer Reference Manual

(

VAX-11 Guide to Creating Modular Library

Procedures

VAX-11/RSX-11M Programmer’s Reference Manual

VAX-11/RSX-11M User’s Guide

Compatibility Mode
Programming

Vil

Table 1: (Cont.) Sources of Information in VAX-11 Documentation
Look in these manuals:

For information on:
Networking

DECnet-VAX System Manager’s Guide

VAX-11 Programming

VAX-11 BASIC Installation Guide and Release Notes
VAX-11 BASIC Language Reference Manual

Languages

DECnet-VAX User’s Guide

VAX-11 BASIC User’s Guide
BLISS Language Guide
BLISS Pocket Guide

VAX-11 BLISS-32 User’s Guide
VAX-11 BLISS-16 User’s Guide
Installing VAX-11 C

Programming in VAX-11 C

VAX-11 COBOL Installation Guide/Release Notes
VAX-11 COBOL Language Reference Manual
VAX-11 COBOL Pocket Guide

VAX-11 COBOL-74 Translator Utility
VAX-11 COBOL User’s Guide

VAX-11 COBOL-74 Installation Guide/Release Notes
VAX-11 COBOL-74 Language Reference Manual

'VAX-11 COBOL-74 User’s Guide

CORAL 66 Language Reference Manual

VAX-11 FORTRAN Installation Guide/Release Notes
VAX-11 FORTRAN Language Reference Manual
VAX-11 FORTRAN User’s Guide

VAX-11 MACRO Language Reference Manual
VAX-11 MACRO User’s Guide

VAX-11 PASCAL Installation Guide/Release Notes
VAX-11 PASCAL Language Reference Manual
VAX-11 PASCAL Primer

M,.-—-—-R\(

VAX-11 PASCAL User’s Guide

Introduction to VAX-11 PL/1
Programming in VAX-11 PL/I

VAX-11 PL/I Encyclopedia Reference

VAX-11 PL/I Guide to Program Debugging
VAX-11 PL/I Installation and System Management
Guide

VAX-11 PL/I Language Summary
VAX-11 PL/I User’s Guide

m
-

>
@)

These

o) (m
m| |

(st
R (50

Graphic Conventions Used in this Primer

symbols

indicate

that

you

press

the

ESCAPE,

RETURN, DELETE, or TAB key on the terminal.

These symbols indicate that you hold down the CTRL key
while you press a terminal key, for example, Y. These sym-

bols represent control key sequences. In some examples,
control key sequences are shown as a circumflex (7) and a
letter, for example "Y, because that is how the system dis-

plays them.

show

time

05 -JUN-1982

11:585:22

In examples of commands you enter and system responses,

all the lines you type are shown in red letters. Everything
the system prints or displays is shown in black letters.

tvPpe

myfile.dat

A vertical ellipsis in an example means that not all the data
the system would display in response to the particular command is shown; or that not all the data a user would enter is

shown.

All commands are

A word or phrase in bold indicates a term defined in the

Glossary at the end of this primer.

Chapter 1

Accessing the System and Typing Commands
To communicate with the VAX/VMS operating system you use a terminal
that is connected to the computer. You tell the operating system what to do
by typing a command or the terminal’s keyboard. The system responds by1t
executing your command. If the system cannot interpret what you type,
displays an error message at your terminal; when the command has been

successfully executed, you type another.

When you communicate with the system in this manner, you are an interactive user. A batch user, in contrast, communicates with the system by submitting all commands at one time in a batch job. This primer emphasizes how

to use VAX/VMS interactively. Chapter 6 shows how any of the commands
described can be submitted in a batch job.

1.1 Terminals

The terminals you can use to communicate with the VAX/VMS operating
system fall into two general categories: hard-copy terminals and video display
|

terminals.

Hard-copy terminals print on continuous forms of paper. Figure 1-1 shows one
type of hard-copy terminal, the LA120.

Figure 1-1:

The LA120 Terminal

1-1

Video display terminals display your typed input and system responses on a
screen similar to that of a television. Figure 1-2 shows an example of a video
display terminal, the VT100.

ZK-759-82

Figure 1-2:

The VT100 Terminal

1.2 Keyboards
Figure 1-3 shows the keyboard layouts of the LLA120 and VT100 terminals. All

terminal keyboards have the same basic configuration as typewriter key-

boards. However, a terminal has additional keys that provide special signals
to the operating system;
to use the terminal effectively, you should become
familiar with these keys.
In Figure 1-3, arrows point to the most commonly used of the special keys.

The symbols in the figure are used throughout this text as a shorthand notation to refer to pressing these special keys. For example, the symbol
text means that you press the key labeled RETURN.

®ED in

means that you

hold down the key labeled CTRL while you press another key. To issue a
CTRLY), for instance, hold the CTRL key down and press the Y key.

1.3 Logging In
\

To begin a session at the terminal, you must log in. Logging in consists of
getting the system’s attention and identifying yourself as an authorized user.
Before you can log in to the system, however, you must have an account.

Accounts are set up by the system manager, or whoever is responsible at your

installation for authorizing the use of the system. This person must provide
you with a user name and a password.
Your user name is a unique name that identifies you to the system and
distinguishes you from other users. In many cases, a user name is your first or

last name.

1-2

Accessing the System and Typing Commands

Your password, however, is for your protection. If you maintain 1ts secrecy,

other users cannot use system resources under your user name or gain access

to files you wish to keep private.

When you log in, you must enter both your user name and your password
before VAX/VMS allows you to begin typing commands.

ol o
‘-l— o o O ° & o o o 0 Ffil
LLLLLL

AL EET

ESC)

e |l@l@
o
; ]
ER L
R IR
FELP
Sci==ns
EllE @%llll@@ljl

(TAB)

LA120

LZ32sest JIUTAR FIFEE
=é=%
@llll.l..l@lll

l@@lll@@llll
353

= oo

o[ R

baio

@@@

o=t

VT100

Figure 1-3:

The LA120 and VT100 Keyboard Layouts

1.3.1 Getting the Terminal Ready
|

Before you use the terminal, be sure that:

e The terminal is plugged in and the power is turned on.

e If the terminal has a LOCAL/REMOTE switch, the switch 1s set to
REMOTE. (If you are using a dial-up connection, check installation
instructions for special procedures.)

The terminal should then be ready to accept your login. If you have any
problems with the login procedure describedin the next section, get help from

the system operator or system manager. The terminal may not be properly
connected to the computer, or the baud rate (the speed at which the terminal
transmits or receives characters) may not be correctly set.

Accessing the System and Typing Commands

1-3

1.3.2

Gaining Access to the System

Press

to signal the system that you want to log in. The system

responds by prompting you for your user name. Enter your user name and
press @ED. The system displays your user name as you type it. After you enter
your user name and press ®ED, the system prompts you to enter your pass-

word. When you type the password, the system does not display it; this
preserves the secrecy of your password.
The login sequence looks like this:
RET)
sername:

MALCOLMEED

assword:

RED
TO

VAX/UMS

VERSION

3.0

WELCOME

The dollar sign is a symbol the system uses as a prompt. When VAX/VMS
displays this character in the left margin, it indicates that the login was
successful and that you can begin entering commands to the system.
Note that if you type your user name or your password incorrectly, the system
displays an error message. When an error message appears, you must repeat
the login procedure.

1.4 Entering Commands
All commands to the system are words, generally verbs, that describe the
functions they perform. You can type them in upper or lower case. For
example:
%

show

time®ED

The system responds to this command by displaying the current date and
time, as follows:
17-JUL-1982

11:55:40

The commands are part of the DIGITAL Command Language (DCL), which
has its own vocabulary of keywords and rules of grammar. The vocabulary
consists of commands, parameters, and qualifiers. The grammar consists of
rules for using these keywords.

Command parameters define what the command will act upon, and command

qualifiers further define how that action will occur. For instance, the PRINT
command below requires an object, or parameter, to indicate what is to be

printed:
%

myfile.lis@®D

In this command, MYFILE.LIS is a parameter for the PRINT command,
indicating the name of the file to be printed. A space separates the command

and its parameter.

1-4

Accessing the System and Typing Commands

Command qualifiers restrict or modify the function the command is to perform. For example:
%

print/copies=2

myfile.lis@®ED
—

In this command, /COPIES=2 is a qualifier that indicates how many copies of
the file MYFILE.LIS you want printed. A slash character (/) precedes the
qualifier.

The entire command string, including the command and any parameters or

qualifiers it may have, is called the command line. The keywords (commands, qualifiers, and parameters) that make up the DIGITAL Command
Language have predefined meanings; therefore, you must use them exactly as
defined, in some cases supplying a value to complete them. For example, the
/COPIES qualifier for the PRINT command requires a value: you supply the
number of copies you want printed.

The rules of grammar for the DIGITAL Command Language (that is, the
order of the words, the spacing, and the punctuation) are also strictly defined.
The VAX/VMS Command Language User’s Guide contains a dictionary of
DCL commands and discusses the rules of grammar.

1.4.1

Command Prompting

When you enter a command at the terminal, you do not need to enter the
entire command on one line. If you enter a command without specifying
required parameters, the system prompts you for the additional data it requires, as shown below:
%

print@D

$_Files:

@ET
myfile,dat

In this example, no parameter was entered, so the system prompted for the
name of the file to be printed.

If a command requires two or more parameters, it prompts for each parameter. In response to each prompt, you can enter just the prompted parameter or
all the remaining parameters. For example:
$

cCoOpPY ‘@J

$_From:

filel.dat@®D

% _Tos

file2.dat
@D

In this example, each file name is entered separately. You could, however,
enter both file names after the first prompt, as shown below:
%

copy @D

% _From:

filel.,.dat

fileZ.dat
@D

You could also enter the entire command line on one line.
$

copy

filel.dat

@ED
fileZ.dat

Accessing the System and Typing Commands

1-5

1.4.2

Abbreviating Commands

When you type commands, qualifiers, or parameters you do not always need
to type the full word. In fact, you never have to type more than the first four
characters, and in many cases you can type only one or two characters. The
rule to follow is: you must type at least the minimum number of characters
necessary to make the command unique.

For example, the SET, SEARCH, and SHOW commands all begin with the
letter “S.” To make the SHOW command unique, you must type at least two
characters, SH. To make the SET and SEARCH commands unique, you must
type three characters, SET and SEA respectively.

The examples in this primer show full commands so that you can become
familiar with the commands and what they do.

1.4.3

Recovering from Errors

Some of the keys noted on the keyboard in Figure 1-3 provide editing func-

tions that you can use to correct mistakes you make while typing commands.
These keys are:
DEL

Backspaces over one character typed on the current line, then deletes the

character. Most video display terminals actually move the cursor (an underline or block that marks your position) backward and erase the character
when you press OfD. Otherwise, the terminal prints a backslash character (\ ),
then each deleted character, then another backslash before it prints the next
character you enter. On some terminals, the key that performs the delete
function is marked RUBOUT.
CTRL/U

Ignores the current line and performs a return so you can reenter the entire

line. Use CRLU

when a line contains a number of mistakes and it would be

tedious to use 0ED.
CTRL/R

Performs a return and displays the current line, leaving the print element or

cursor at the end of the line so you can continue typing input. Use

when

you have deleted a lot of characters on a line, and cannot read the line easily

promynoNint muNu\yCRLUR)

because of the backslash characters. For example:

Print my

CTRLIO

and CTRLY

Cancel an entire command, regardless of how many lines were used to enter it.

1-6

Accessing the System and Typing Commands

to interrupt the system while it is executing a
or
You can also use
command. Such an interruption is useful in cases when you have entered a
(or €TRLC)) and then issue the
command and you want to stop it. Press
STOP command, as shown below:
$

type

mvfile.lis@E

CTRLIY)
% stor@ED
&

In this example,

interrupted the typing of a long file and the STOP

command terminated the output.
and CTALQ

To suspend and resume the upward movement, or scrolling, of the terminal
and €9. To temporarily stop the display from scrolling,
display, use
press CALS); to continue the scrolling, press €A. (The NO SCROLL key on
VT100 terminals performs the same function.)

1.5 System Responses

The system can respond to your command in several ways. It can execute the
command, indicating successful completion with the dollar sign prompt. It
can execute the command and inform you in a message of what it has done. It
can, if execution is not successful, inform you of errors you have made. It can
even act for you, supplying values that you have not supplied yourself.
1.5.1

Defaults

A default is the value supplied by the operating system when you do not
specify one yourself. For instance, if you do not specify the number of copies
as a qualifier for the PRINT command, the system uses the default value of 1.
By not explicitly stating a choice, you imply the default. VAX/VMS supplies
default values in several areas, including command qualifiers and parameters.
The defaults used with individual commands are specified with each command’s description in the VAX/VMS Command Language User’s Guide.
1.5.2

Information Messages

The system responds to some commands by giving you information about
what it has done. For example, when you use the PRINT command, the
system displays the job identification number it assigned to the print job and
shows the print queue the job has entered.
$

Jobh

mvfile.lis@®ET

210

entered

sueus

SYSEHEFPRINT

Accessing the System and Typing Commands

1-7

Not all commands display informational messages; in fact, successful completion of a command is most commonly indicated by a dollar sign prompt for
another command. Unsuccessful completion is always indicated by one or
more error messages.

1.5.3

Error Messages

If you enter a command incorrectly, the system displays an error message and

prompts for a command line as if no command had been entered:
%

capvy BED

YDCL-W-IVVERB:

unrecodnized

command

NCAPYA
&

The three-part code preceding the text of the message indicates that the

message is from DCL, the command interpreter; that it is a warning (W)
message; and that the mnemonic for this particular message is [IVVERB.
You can also receive error messages during command execution if the system
cannot perform the function you have requested. For example, if you type a
PRINT command correctly, but the file that you specify does not exist, the
PRINT command informs you of the error:
%

nofile.dat®D

YPRINT-W-0PENIN:
as

error

orpening

DBA1:IMALCOLMINOFILE
. .DAT S

input

~RMS-E-FNF:

file

not

found

The first message is from the PRINT command: it tells you it cannot open the
specified file. The second message indicates the reason for the first, that is,
the file cannot be found. “RMS” refers to the VAX/VMS filehandling facility, Record Management Services; error messages related to file
handling are generally VAX-11 RMS messages.

1.6 The HELP Command
When you use the VAX/VMS operating system, you may not always have a
reference manual available at your terminal, and you may want to see the
format of a command before you enter it. The HELP command is designed to
provide you with this information.

For example, to display a list of commands for which HELP is available, type:
%

help@ED

The system responds by displaying the list of commands and prompting for a
choice of topic.

1-8

Accessing g the System
and Typing
3
yping Commands

If you want information about a particular command, type that command
after the prompt. For instance, if you want information about the PRINT
command, type:
Toric?

Print@®ED

The information displayed includes a synopsis of what the PRINT command
does, the parameters it requires, and the qualifiers it can take.
If you want to know more about one of the PRINT command’s qualifiers,
respond to the prompt “PRINT subtopic?” with that qualifier. For example,
to display information about the /COPIES qualifier of the PRINT command,
type:

subtopic?

/cories@®ED

If you know the subtopic on which you need help to begin with, you can
simply type:
%

help

print/cories(@ET

When you have finished using HELP, type CRz). The dollar sign prompt will
appear in the left margin, indicating that VAX/VMS is ready to receive a
command.

1.7 Logging Out
When you have finished using the computer, use the LOGOUT command to
end the terminal session:
¢

lodout
RET

The system responds:
MALCOLHM

lodded

out

17-JUL-1898%

12:43:10.38

Note that neither shutting off your terminal, nor setting the REMOTE/-

LOCAL switch to LOCAL, automatically causes you to log out. To ensure
that you have logged out, you should use the LOGOUT command to end a
terminal session. If you shut a terminal off without logging out properly,
another user may be able to turn the terminal on later and use your account.

1.8 For More Information
The VAX/VMS Command Language User’s Guide is the primary reference
manual for information about the DIGITAL Command Language. The manual contains complete descriptions of DCL, commands, defines the grammar
of the DCL command language, and illustrates command usage with many
examples.

Accessing the System and Typing Commands

1-9

Chapter 2

Using an Editor: EDT

“\“,

Before you use the VAX/VMS operating system, you need to know how to
identify and create files. This chapter briefly describes file identification and
editing with the EDT editor. If you are familiar with editors, you may want to
3, Commands to Manipulate
skip this chapter and go directly to Chapter
|

Files.

2.1 Files

A file is the basic unit of storage for VAX/VMS. All user information 1s stored
in files, usually on auxiliary storage media such as magnetic tapes or disks. In

order to retrieve a file from storage or to create and store a new one, you must
be able to identify the file for the system.

te
VAX/VMS uses a unique file specification to identify each file. A complethe
file specification includes the user’s network node, the device on which
file is stored, the directory in which the file is cataloged, and the name, type,
and version of the file. Only the file name, type, and version are discuss3.ed
here. For a more complete explanation of file specifications, see Chapter
2.1.1

File Names

By taking advantage of defaults, you can identify a file by specifying only its
file name and file type in the format:
filename. LypPe

A
The file name can have up to nine characters selected from the lettersgive
can
you
files,
create
you
When
through Z and the numbers 0 through 9.

- them any names that are meaningful to you.

2.1.2 File Types

ed by a
The file type can be from zero to three characters and must be preced
rs 0
numbe
the
and
Z
h
period. Again, you can choose from the letters A throug

2-1

through 9 for the file type. However, the file type usually describes specifically
the kind of data in the file, and the system recognizes several default file types
used for special purposes. (See Sections 3.1.4 and 4.1 for tables of default file
types.)

2.1.3

File Versions

In addition to a file name and file type, every file also has a version number to
distinguish it from other copies of the file. The version number is the last item
in the file specification and is connected to the file type by a semicolon (;) or a

period (.). The following example shows the format for version two of the file
MYFILE.DAT:
myfile.dats?

The system supplies version numbers by default if you do not specify them
yourself. When you create a file, the system always assigns it a version number of 1. When you edit the file, its version number is automatically increased
by 1. If you refer to an existing file without specifying a version number, the
system always locates the most recent version (that is, the file with the highest version number).

You can override these default version numbers by explicitly specifying a
version number:
$

myfile.dat
i3

This PRINT command requests that the third version of the file MYFILE.DAT be printed.

2.2 Editors
To edit a file you use a program called an editor, which has its own set of
commands for modifying files. VAX/VMS supports four editors. (There may

be other editors in addition to these at your installation.) Two, SUM and
SUMSLP, are batch editors. To use a batch editor, you submit a list of the
changes you want made to the file and the editor makes the changes as a

batch job.
VAX/VMS also supports the SOS and EDT editors. With both, you conduct
an interactive editing session: you give an editing command to which the

editor responds. This interaction continues until you give the final command
to store or delete the edits you have made.

To invoke any of these editors type the EDIT command, specifying as a

qualifier the name of the editor you want to use and, as a parameter, the name
and type of the file you want to edit. For example, to invoke SOS to edit the

file MYFILE.DAT type:
$

2-2

edit/sos

Using an Editor:

EDT

myfile.dat

Because /EDT is the default qualifier for the EDIT command, you invoke the
EDT editor when you type:
myfile.dat

edit

2.3 Introduction to EDT
The DIGITAL Standard Editor, EDT, has a number of advanced features
that allow you to tailor it to your own needs. Some of these features are
mentioned in Section 2.6; however, most are beyond the scope of this primer.
For other sources of information about EDT and other editors, see Section 2.7.

EDT provides two basic methods of editing: line and keypad editing. When
you use EDT’s line editor, you specify both the editing command and the
line(s) of text you want the command to affect. The EDT line editor is available on both hard-copy and video display terminals.

The EDT keypad editor is designed to be used on video terminals that display
the editing as it takes place. When you use EDT’s keypad editor, you move
the cursor directly to the text you want to change and press either one or two
keys to perform most of the commands.

If you use a video terminal, you can use both keypad and line editing in EDT.
If you use a hard-copy terminal, you should skip Section 2.4 and go to Section
2.5, Line Editing in EDT.

2.4 Keypad Editing in EDT

The keypad is the small group of keys to the right of the larger keyboard on
your terminal. Each key in the keypad performs at least one editing function;
most of the keys perform two.

As you can see in the figure below, the keypads of the V1100 and the VT52
differ slightly, so that the keys performing a particular command are not
always the same on both terminals. Therefore, the sample editing sessions
that follow generally refer to the command (WORD) and its function (moves
the cursor forward or backward in word units), rather than to the key itself
(key 1). To learn which functions the keys on your keypad perform, refer to
the diagrams below or the EDT Editor Reference Card.
coto

)

vp
oELL || semace
mor.

HELe

LeFT

J
Je
—

)

—

FNONXT
PAGE
commano || Fmo

aovance || sacxue

BOTTOM

WORD

oW
sect

oEL W
uNo W

RIGHT

oELC

SPECINS

uND C

—

LEFT

cut

cHnGease || DELEOL

PASTE

APPEND

——
[
LINE
OPEN LINE

16
seLeCT
RESET

21
ENTER
suss

e S

RIGHT

coLo

—

)

—

PAGE
command

Hew?

]

—

aovance || sacxue

cut

PASTE

TOP

BOTTOM

oELL
e

oeLC

uNoC

L__a ) L__a rDU
1

WORD

EoL

CcHAR

cuncease || oeLeol || seecins

LINE
OPEN LINE

16
SELECT
RESET

enten

suss

JuL__J

VvT100

V152

Figure 2-1:

)

avpeno || oeLw
repuace || unow

sect
FiLL

)

- Jt__J

FNONXT
sl

J
-

—————

x.762.82

The VT52 and VT100 Keypads

Using an Editor:

EDT

2-3

2.4.1

The Gold Key

As Figure 2-1 illustrates, most of the keys perform two editing functions. To

use the alternate, or lower, function of a key, press the GOLD key before you
press the second key. For example, key 1 (on both the VT52 and the VT100)
performs two functions: WORD and CHNGCASE (Change Case). To enter
the WORD command, press key 1; to enter the CHNGCASE command, press

the GOLD key first and then key 1.
In the examples that follow, small diagrams of the VT'52 and VT'100 keypads

highlight the keys that perform the command being described. The text to the
left of the diagrams displays the effect of the command. For example, the
CHNGCASE command is pictured as:

H000
oad
Jood
RO00
o0
VT52

RQO0
g
goog
BO0
g
VT100

Note that the GOLD key must be pressed before the second key in order to
invoke that key’s alternate function.

2.4.2

The HELP Command

The EDT keypad editor provides a HELP key that displays a diagram of the
keypad and the various key functions:

Oe0og

ooog
uotd
ooog
(I
VT52

o
g
d
N

[

VT100

If you want information about a specific key, press the HELP key and then
press the key in question. For example, if you want to know the function of the

WORD command, press the HELP key to find which key performs the WORD
function and then press key 1 for an explanation.

You can continue to get help on specific keys by pressing them. When you
want to return to your editing, type a space. EDT resumes the display of your

file, returning the cursor to its previous position.

2.4.3

Creating a File

To create a file with EDT, type the EDIT command, specifying the file’s
name as a parameter:

edit

Input

myfile.dat
file

[EOBI]
*

2-4

Using an Editor:

EDT

does

not

exist

The first line that appears is the message “Input file does not exist” telling

you that you have no existing file named MYFILE.DAT (since you are creat-

ing that file). The second line, “[EOB],” denotes the end of the buffer, the
temporary storage area in which you edit text before it is stored in a file. The
third line, the asterisk, is the EDT line editor prompt.

To use EDT’s keypad editor, type “C” (for the CHANGE command) after the
asterisk prompt and press RETURN. The screen goes blank with only [EOB]
in the upper left hand corner, indicating that there is nothing currently stored
in the buffer. (In keypad editing, EDT always displays the [EOB] symbol on
the line after the last character in the buffer.)

Using the main keyboard, type the following text to create a new file:
Hevs diddle diddle: G
the cat plaved the fiddle: @ED
the cow Jumped ouer the moon. G
This is the fourth line. G@ET
Use CTRL/Z to chande from @
kevepad

line

editing.

CEOBI]

What you type is not recorded in a file until you instruct EDT to copy what
you have entered from the temporary storage of a buffer to a file. You can then
retrieve the file at a later time and make changes to it, such as adding and
deleting text.

To save, or store, your edits, enter the EXIT command. First, invoke the line
mode prompt by typing €W®Uz). Then type EXIT after the asterisk and press
RETURN:

’

—

oo
T

ev: diddle diddle:
cat plaved the fiddle:
th
the moon.
¥ g cow Jumped over
is the fourth line.
h1 is
e CTRL/Z to chande from

ypad

E 081

line

editing.CRUZ

HITRED

When you enter the EXIT command, the system saves the contents of the
buffer in a file named MYFILE.DAT;1, issues the message below, and returns

you to the DCL command level:

DEZ: [MALCOLMIMYFILE.DATI1

lines

4§

If you do not want to save the edits you have just made, type QUIT after the
asterisk prompt. EDT will delete the contents of the buffer without creating a
file and return you to the DCL command level.

Using an Editor:

EDT

2-5

2.4.4

Editing a File

You invoke EDT to edit an existing file the same way you do to create one:
type the EDIT command, specifying the file name as a parameter.

Heys

diddle

diddle:

The first line of the latest version of the file, as well as the line editor prompt,
will appear on the screen. (Note that if you type the wrong file name in the
EDIT command line, you can terminate EDT without altering that file by
using the QUIT command.)
Type “C” for the CHANGE command to switch from line to keypad editing:
EDT displays the first 22 lines of your file on your screen. (The ED'T keypad
editor does not display line numbers.)
Hevs

diddle

diddle:

the

cat

rplaved

the

cow

Jdumeed

over

This

kevepad

the
to

fourth

line

fiddle:

the

moon.

line.

editing.

[EOB]

You can now begin editing your file.

2.4.5

Manipulating the Cursor

The right and left arrow keys move the cursor one character in the direction of
the arrow on the key. (When the left arrow is at the beginning of a line,
however, it moves vertically, and when the right arrow is at the end of a line of
text or the beginning of a blank line, it also moves vertically.) The location of
the arrow keys on your terminal depends on whether you have a VT52 or a
VT100:

Hnn |
BEN| |
00
VT52

2-6

Using an Editor:

EDT

HEEE

(000

O]
]
L]
B

m[EE

Hog
Hoog

BN
10

VTi00

K evpad

|:|[:][:]

calt

FPlayel

[

This is the fourth line.
to

line

editing.

CEOB]

DDDD
VT52

DDDD

Lhe

the cow Jumeped over the moon.

w00
|
| |
eJO0O00
(||
O

You can also move the cursor by larger units of text, such as words, lines,
sections, and pages. For example, give the WORD command to move the
cursor to the beginning of the next word:

(If your cursor does not move as described, it may be set to move backward
rather than forward. See Section 2.4.7 to change the cursor’s direction.)
There are several ways to move through a file by line. To move the cursor to
the end of the line, give the EOL (End Of Line) command:

Hevy digdle diddle,

0000

0ood

This is the fourth line.

DDDD

the oo sumred aver
the meon.
kevepad

line

editing.

OeHH

‘___]DD

CEOB]

VT52

UL
[—__H:]
VT100

(The BACKSPACE key on the main keyboard moves the cursor in the opposite direction — to the left margin.) To move up or down a line you can use the
up and down arrows, or you can use the LINE command, which moves the
cursor to the beginning of the next line:

the

cow

Jumped

ouver

the

moon:

This is t.hi; fourth 1i'rn3+H
kevepad

line

editing.

CEOB]

2.4.6

)

DDDD

-DD

-D

VT52

VT100

Scanning a File

In addition to moving the cursor by character, word, and line units, you can

scan several lines of text at a time with the SECT (Section) and PAGE

Using an Editor:

EDT

2-7

commands. SECT moves the cursor across a 16-line section of text; PAGE
moves the cursor across a page' of text.

Loy e

2
F

LEOB

line

editing.

DDDD

.DDD
DDD

(]

momowm

This is the fourth line.

VT52

—

Lre

the cow Jdumped over the moon.

. [ |
(|
1|
|
.
(I

Another way to move the cursor quickly through a large portion of text is to
move it directly to the beginning or end of the file. The BOTTOM command
moves the cursor to the line following the last character:

The TOP command moves it to the first character:

Hev,

diddle diddle,

)

TRE saw lbmesd D08
The mamn.

This is the fourth line:.
CEOE]

2.4.7

pO0Og

puod

oooo

VT52

VT100

D.DD

Changing the Cursor’s Direction

Many commands (including the CHAR, WORD, LINE, EOL, SECT, and
PAGE commands) move the cursor forward or backward unit by unit, depending upon whether you last set the direction of the cursor with the ADVANCE or BACKUP command. Each of these commands controls the cursor’s direction until you set the cursor in the opposite direction with the other
command.

To illustrate: give the BACKUP command to set the cursor in the backward
direction. (The cursor does not move when you set its direction.)
Hevs diddle
the

cat

diddle,

plaved

the

0000

Oogn

D.DD

VT52

VT100

fiddle
:

This is the fourth line.
CEOBI]

1. By default a PAGE is defined as the text between form feed characters (ASCII characters
that determine the start of each line printer page).

2-8

Using an Editor:

EDT

Now move the cursor one word (backward) with the WORD command:

This is the fourth line.

DDDD

kEevead

:]DD

C]D

line

editing.

CEOB]

VT52

Backur

past

tor

VT100

buffer

You should hear a bell (or buzzer) and see a message indicating that the
command requests EDT to backup past the top of the buffer. Now reset the
cursor’s direction with the ADVANCE command. (Again, the cursor does not
move.)

the ocow Jdumped ouver the moon.
Lhe

cat

L ay

Lie

1 e
s

This is the fourth line.
[EOB]

E)DDD

DDDD

VT52

VT100

[:IDD

.DDD

Move the cursor forward one word with the WORD command:

DDDD

[
I |[
(|

the cow Jdumeed over the moon.

This is the fourth line:.

[
0
[

VT52

VT100

DDDD

Eevra
CEOB]

This time the cursor moves forward to the beginning of the next word. The
cursor will remain set in this direction until you give the BACKUP command;
you can change the cursor’s direction whenever it is convenient.
2.4.8

Deleting and Restoring Text

The delete commands work in units similar to those that manipulate the
cursor: there are commands to delete by character, by word, and by line. The
deleted text is stored in a buffer so that you can restore it with an undelete
command.

Using an Editor:

EDT

2-9

The delete and undelete commands work in the same way: you can delete by
character (DEL C), word (DEL W), or line (DEL L); and you can restore that

character (UND C), word (UND W), or line (UND L). For example, enter the
DEL L (Delete Line) command:
Hev:

the

cat

This is the fourth line.

Use CTRL/Z to chande from
kevrpad

line

editing.

CEOBI]

OoOm0O
[][][j[]

[][][j[]

[::j[][j

[Qgos
[][][][]

[][][j
[::j[]

VT52

VT100

The deleted line disappears and is replaced on the screen by the line following
it. Now give the UND L (Undelete Line) command to restore the line:

the cow Jumred over the moon.

nUmC
moos
noog - 0o

Use CTRL/Z to chande from

[j[j[][]

This is the fourth line.
kevead

line

editing.

LEOB]

DDDD
[::Mj[]

DDDD

[j[][]

E:][j

VT52

VT100

The line reappears. The UND C (Undelete Character) and UND W (Undelete
Word) commands work in exactly the same way, allowing you to restore the
last character or word you deleted.

Note that the undelete commands restore only the corresponding units of text

that were most recently deleted. If you have deleted two lines of text with the
DEL L (Delete Line) command, for example, the UND L (Undelete Line)
command will restore only one line — the line most recently deleted.
2.4.9

Locating Text

In addition to scanning text, you can move the cursor to a specific location in

the file with the FIND and FNDNXT commands. The FIND command
searches for a particular character string between the current position of the
cursor and the beginning or end of the buffer, depending on whether the
ADVANCE or BACKUP command is in control. The FIND command is espe-

cially useful with long files that would be tedious to scan with other commands.

For example, if you want to edit a particular string of text, specify that string

and EDT will search for it. If EDT finds the string, the cursor will move to the
beginning of the string. If EDT cannot find the string, the bell will ring and
the message ‘‘String was not found” will appear on the screen.

2-10

Using an Editor:

EDT

Assume you want to locate the word MOON. You could instruct EDT to
search for the string by first giving the FIND command to invoke the Search

line

editing.

VT52

0000w
]

[__—]DD

[EOB]

kevepad

D D

E].ED

the cow Jumped over the moon.

This is the fourth line.

(]|

prompt.

for:

Type MOON in response to the prompt and then press ADVANCE (since you

kevepad

the
to

fourth

line

the

moon.

line.

editing.

[EOB]

VT52

|
.

| [
|

This

fiddle:

[
(I

over

Jumped

cow

the

| (I
| [

plaved

diddle:

cat

O
I
| ¢

diddle

the

i0
[

Heys

want EDT to search in the forward direction).

When EDT finds the string, it positions the cursor at the first character in the
string. (In a long file the message “Working” may flash on the screen while
EDT searches for the string.)

To find the next occurrence of the same string, give the FNDNXT (Find
Next) command. If there is no other occurrence of the string (as in this
instance), EDT will issue the message ‘‘String was not found.”
Note that the directional setting of the cursor determines the outcome of the
search. You can use either ADVANCE or BACKUP to enter the search string,
depending on the direction in which you want the cursor to search. (You can
also use the ENTER command, which applies the current direction to the
search.)

2.4.10

Moving Text

Moving text from one place to another in a file is called “cutting and pasting”
in EDT: you cut out the text you want to move and paste it in the place where

you want it. The first step in this operation is to select the range of text you
want to move.

Using an Editor:

EDT

2-11

For example, to move the first line of text to the end of the file, move the

cursor to the beginning of line one and press SELECT. This marks the beginning of the select range.
ey,
He>

diddles

diddle

the

cat

eplaved

the

cow

Jumped

over

fiddle:
the

This is the fourth line:.

moovn.

Use CTRL/Z to chande from
kevepad

line

editing.

[EOB]

0ood

DDDD

l:].[:]
VT52

0doo
DDDD

DDDD

DDD
[:] ]
VT100

To mark the end of the select range, move the cursor to the end of line one. All
text between the select point and the cursor will be affected by the CUT
command. (A VT100 highlights the select range with reverse video.) Now
press CUT:

the cat Plaved the fiddle.
pE.
Use CTRL/Z to change from
the

cow

This

Jumeped
the

Keypad

over

fourth

line

the

moon.

line.

editing.

CEOB]

%%%E
0000
DD.D

[:'“:]D
VT52

The select range (in this case, line one) disappears from the screen. EDT holds
the text you delete with the CUT command in the PASTE buffer. To restore
it, move the cursor to the location where you want to place the text and enter
the PASTE command. For this example, move the cursor to the end of the

This is the fourth line.
L

guer

Lne

moon.

Use CTRL/Z to chande from
kevepad to line editing.

Hevs

diddle

diddles_

[EOB]

DDDD

DDDD
DD.D

DDD
VT52

[
a
i

OOmn)

Mo oow Gumeed Duer She wep

DE][:H:I
DDE]-

file. Now enter the PASTE command:

misl
VTxoo

You can continue to use the PASTE command wherever you wish, since the
text remains in the paste buffer until it is replaced by another CUT operation.
The CUT and PASTE commands are especially useful in moving large pieces
of text from one place to another in a file.

Select ranges are also used with other commands, such as the APPEND,
FILL, and SUBSTITUTE commands. If you make a mistake during the process of marking the select range (or any keypad command requiring a
sequence of keys), use the RESET command to cancel the first part of the
command and start over.

2-12

Using an Editor:

EDT

2.4.11

Entering Line Commands in Keypad Mode

Occasionally, you may want to use line editing commands without actually
changing from keypad to line mode. You can do so with the COMMAND

function.

For example, to give the SET QUIET line command (which suppresses the
ringing of the bell or buzzer when an EDT error occurs), first invoke the

cow

Use

CTRL/Z

over

chande

the

moon.

from

Kevead to line editing.

5%%%
DDDD

l:][:][j

Hev: diddle diddle:

VT52

LEOBI]

Command:

SET

Jumped

the

This is the fourth line.

mm
| |
||
|
eJ100]
1004

Command: prompt. Then type the command after the prompt.

QUIET_

Use ENTER to submit the command. (If you press RETURN by mistake, "M

the

moon.

This is the fourth line.
from
the

cow

.Jumped

over

Use CTRL/Z to chande

kevrpad to line editind.

Hevs diddle diddles
[EOB]

DDDD

HIRRE

J0OW
C
VT52

the cat rplaved the fiddle:

I [O [
Ooddd
=
I
|
.0

will appear. Delete the "M and press ENTER.)

You can also enter the EXIT and QUIT commands with the COMMAND
function.

2.4.12 Changing From Keypad to Line Editing

If at some point during keypad editing you want to change to line editing,
type €ML2). The line-editing prompt, an asterisk, will appear at the bottom of
the screen, indicating that EDT is ready to receive line-editing commands.
2.4.13 Subset of EDT Keypad-Editing Commands

Table 2-1 presents some of the most frequently used keypad commands and
the main function of each. For a complete list of EDT keypad commands, see
the EDT Editor Manual.

Using an Editor:

EDT

2-13

Table 2-1:

Subset of EDT Keypad-Editing Commands

Command

Function

ADVANCE

Sets cursor movement in forward direction

BACKUP

Sets cursor movement in backward direction

BOTTOM

-Moves the cursor to the bottom of the buffer

CHNGCASE

Changes the case of specified characters

CUT

Deletes specified text from the main buffer and stores it in the paste buffer

- DEL C
-

Deletes‘ the character at the cursor

DEL EOL

Deletes text from the cursor to the end of the current line

DEL L

Deletes text from the cursor through the end of the current line, moving
the following line up to the cursor

DEL W

Deletes text up to the first character of the next word

EOL

Moves the cursor to the end of the current line

FIND

Locates specified text

FNDNXT

Locates the next occurrence of specified text

HELP

Invokes EDT’s keypad help facility

LINE

Moves the cursor to the beginning of the next line

PAGE

Moves the cursor across one page of text

PASTE

Inserts the contents of the paste buffer at the cursor’s position

RESET

Cancels GOLD, SELECT, or any key sequence

SECT

Moves the cursor across 16 lines of text

SUBS

Deletes specified text and inserts the contents of paste buffer

TOP

Moves the cursor to the top of the current buffer

UND C

Restores the character deleted by the last DEL C

UND L

Restores the line deleted by the last DEL L

UND W

Restores the word deleted by the last DEL W

WORD

Moves the cursor one word

Restores the video display

Changes from keypad editing to line editing

2.5 Line Editing in EDT
In line editing, you do not move the cursor directly to the character or word
you want to edit. Instead, you type the command and specify the line or range

of lines you want the command to affect. (Although most of the line- editing
commands can be abbreviated, this chapter presents the full commands SO

that you will recognize their functions.)

2-14

Using an Editor:

EDT

2.5.1

The HELP Command

The EDT line editor has a HELP command, which works much like the DCL
command HELP. If you need help with EDT line commands, type HELP
after the asterisk prompt, and EDT will display all the line-editing commands
available. To get help with a particular command, type HELP and the name
of the command (for example, HELP TYPE); EDT will display information
about that command.

2.5.2

Creating a File

To create a file with EDT’s line editor, give the EDIT command, specifying
the file’s name as a parameter:
¢t

edit

Input

vourfile.dat

file

does

not

exist

LEOBI]
¥

The first line is the message “Input file does not exist,” indicating that you
have no file in your default directory with the name YOURFILE.DAT (since
you are creating that file). The second line, “[EOB]),” denotes the end of the
buffer, the temporary storage area in which you edit text before storing it in a
file. The third line, the asterisk, is the prompt for EDT’s line editor.
To insert text in your file, type INSERT after the prompt and press RETURN: the cursor moves forward several spaces. EDT inserts what you type
after this command as text until you signal completion with CTRLZ).
Type the following lines from the main keyboard, using the DELETE key and
ALY, which deletes text between the cursor and the left margin if you make a
mistake. (You cannot return to a preceding line to make an addition or correction once you have pressed RETURN, unless you give additional commands.)
@ED
# INSERT

ev:

the

diddle

cat

diddle :@ET

plaved

the

fiddle :@ED

the cow Jumped over the moon. CTRL2)

[EOB]
*

Terminate the insertion of text by typing €®iz). EDT displays the [EOB] sign
and asterisk prompt, indicating it is ready to receive another line-editing
command.

When you use EDT, what you type is not recorded in a file until you instruct
the editor to copy your text from the temporary storage of a buffer to a file,
which you can later retrieve for editing. When you enter the EXIT command,

EDT saves the contents of the buffer in a file named YOURFILE.DAT;1,

Using an Editor:

EDT

2-15

issues the message below, and returns you to the DCL command level (signified by the dollar sign prompt). Type EXIT after the asterisk prompt:
¥EXITRE
DBZ:[MALCOLMIYOURFILE.DATSL

lines

If you do not want to save your edits, type QUIT after the prompt. EDT will
delete the contents of the buffer without creating a file and return you to the

DCL command level.

2.5.3

Editing a File

You enter and exit EDT to edit an existing file the same way you do to create

one. To invoke EDT, give the EDIT command and specify the file name as a
parameter. The first line of the latest version of the file, as well as the line

editor prompt will appear.
%

edit

vourfile.dat

Hev:

diddle

diddle:

Note that if you type the wrong file name in the EDIT command line, you can
terminate EDT without altering that file by using the QUIT command.

2.5.4

Specifying Ranges

EDT initially assigns line numbers in increments of one to each line in the

buffer. You can use these numbers to specify the line or range of lines you
want the command to act upon. EDT also recognizes certain words in range
specifications; you can combine these words with line numbers in a range
specification. For example, if you want to delete the first two lines in the file,
you could type: “DELETE 1 THRU 2” or “DELETE BEGIN:2.”
Table 2-2 lists a small subset of range specifications possible in line editing to

help you begin using the line editor. Once you have begun, you can use the
line editor’s HELP facility and the EDT Editor Manual for complete instructions on specifying ranges.

Table 2-2:

Subset of EDT Line-Editing Range Specifications

Specification

Desecription
The current line

2-16

n THRU n

Line number n through line number n

n:n

Line number n through line number n

BEGIN

The first line of the buffer

END

The empty line after the last line of the buffer

BEFORE

All the lines before the current line

REST

The lines including and after the current line

WHOLE

All the lines in the buffer

Using an Editor:

EDT

In addition to using range specifications, you can press ®ED to move forward
one line:

Hev:

diddle

diddle:

the

cat

rplaved

the

cow

Jumped

over

fiddle:
the

moon:

Inserting and Deleting Text

2.5.5

The INSERT and DELETE commands take similar parameters. When you
specify a range, EDT inserts the text before the first line of the specified
range. (If you do not specify a range, EDT inserts the text immediately before
the current line.) For example, to add text to the end of the buffer, you could
specify line four or END to indicate the end of the buffer:
# INSERT

END

®ET

the

This

fraom

line

line.®

fourth

to Hevyrpad editing CTRL Z

[EOB]
¥

Terminate the insertion of text with €m2). EDT assigns line numbers to the
new text and issues an asterisk prompt, indicating that it is ready to receive
another editing command.

The DELETE command works in much the same way, deleting those lines of
text specified in the range. If you do not specify a range, the current line is
deleted by default. (There is no line-editing command equivalent to the
UNDELETE keypad commands.)
Locating Text

2.5.6

To display the entire contents of the buffer, use the TYPE command and
specify WHOLE as the parameter:
#*TYPE

WHOLE GET

2
3
i
5
B

Hey s

diddle

diddle:

the cat plaved the fiddle:
the cow Jumped ouver the moon.
This is the fourth line:
Tyee CHAMGE to switch
from line to Kevypad editing:

EEOB]

If you want to locate a text string in a long file without displaying the entire
buffer contents, you can use quotation marks. For example, to find the first
occurrence of the word FOURTH, type:
*"fourth" @

This

the

fourth

line:

kT3

Using an Editor:

EDT

2-17

EDT moves the cursor to the line containing the first occurrence of the string.
If you want to display all occurrences of the string, use the TYPE ALL command, followed by the string in quotation marks.

2.5.7

Substituting Text

To replace one character string in the current line with another, use the
SUBSTITUTE command. To replace every occurrence of one string with
another throughout the file, use WHOLE as the parameter.
For example, to replace all occurrences of the string THE with the string A,
type SUBSTITUTE, the old string, and the new string, separating all three
with delimiters, such as slashes. (You must use the same delimiter throughout the command line.) Then specify WHOLE as the parameter:
*SUBSTITIUTE/the/a/WHOLE
@D

cat

plaved

cow

JumpPed

ouer

This

fTiddle

fourth

moon
.

line.

subhstitutions

EDT displays the total number of substitutions made and issues the asterisk
prompt.

2.5.8

Copying and Moving Text

The MOVE command in line editing is similar to the CUT and PASTE
commands in keypad editing: the MOVE command deletes text in one location and inserts it in another. The COPY command, in contrast, duplicates a
range of text in another location, without altering the original text.

For example, with the COPY command you can duplicate the entire file: first
type the command, then the range of lines to be copied, and finally the range

of lines to which you want to copy the text.
*COPY

1:6

lines

END

copied

Lines 1 through 6 are duplicated in lines 7 through 12. (You can display the

change with TYPE WHOLE.)

When you have finished editing your file and are ready to store your changes,
enter the EXIT command (as described in Section 2.5.2).

2.5.9

Changing from Line to Keypad Editing

If at some point you want to change from line editing to keypad editing, give

the CHANGE command by typing “C’ after the asterisk prompt. The screen

will display without line numbers the first 22 lines of the file, and you can
begin keypad editing immediately.

2-18

Using an Editor:

EDT

2 510 Subset of EDT Line-Editing Commands
Table 2-3 presents some of the more frequently used EDT line-editing com-

mands and the main function of each. For a complete list of commands, see

the EDT Editor Manual.

Table 2-3: Subset of EDT Line-Editing Commands
Function

Command

CHANGE
COPY

DELETE

Chénges from line editing to keypad editing
Duplicates text in specified location

Deletes specified range of lines

Ends an editing session by storing the buffer contents in a file

EXIT
FIND
HELP

INCLUDE

INSERT
MOVE

QUIT

Locates specified line
Invokes EDT’s line editing help facility

Copies specified file into textl buffer

|
Inserts text in the buffer
Deletes text in one location and inserts it in another
Ends an editing session by deleting the contents of the buffer

SUBSTITUTE

Assigns new line numbers in increments of one
Replaces one character string with another

TYPE

Displays a specified range of lines

RESEQUENCE

WRITE

Copies a specified range from the buffer to the specified file

2.6 Special Features of EDT

EDT offers several special features, a few of which are mentioned here. For
more information about these and other features of EDT, see the EDT Editor
Manual.

2.6.1 Multiple Buffers

When you edit a file with EDT, you are working on a copy of the file in a
buffer called MAIN. There are other buffers in addition to this main buffer.
One buffer, called PASTE, is maintained by EDT for its own use, but the
others are available for you to use as separate workspaces.

These additional buffers are useful in working with multiple pieces of text.
You can move part or all of a buffer into another buffer or several other
buffers. You can also copy a file into one of these buffers. To create a buffer for
additional workspace, you first name it, after which you can enter and exit
that buffer at any time.

2.6.2

Journal Files

This
When you edit a file with EDT, EDT keeps a journal file of all your edits.
file has the same file name as the file you are working on and the file type of
‘Using an Editor:

EDT

2-19

JOU. Should a system failure or inadvertent

end your editing session,

the journal file has a record of all your edits, with the possible exception of
those made just prior to the interruption.

To recover your lost edits, you use the same EDIT command and the exact

qualifiers you used to begin the original editing session
— plus the /RECOVER qualifier. For instance, if you began a session with the command

EDIT YOURFILE.DAT, you would type EDIT/RECOVER YOURFILE.DAT
to recover your edits using the journal file. EDT will then reenact the editing
session, reading the commands from the journal file and executing them on

the screen.
If no interruption occurs, EDT deletes the journal file when you exit from the
editing session.

2.6.3

SET and SHOW Commands

The SET commands let you control certain characteristics of EDT’s operation

by setting certain parameters. Among the characteristics that you can set are:
the length of line displayed on the screen (SET SCREEN width), the default
~delimiters for textual units, such as words and sentences (SET ENTITY), and
the display of line numbers during line editing (SETINOINUMBERS). The

SHOW commands display most of the characteristics you can set with the

SET command.

2.6.4 Start-up Command Files
You can create an EDT start-up command file to specify the default characteristics for editing sessions. EDT looks for a start-up command file when you
begin an editing session; if you have one, it reads the commands and applies

the specifications to the current editing session. For example, if you place the
command SET MODE CHANGE in your start-up command file, you will

begin editing in keypad mode whenever you enter EDT.

2.6.5

Defining Keys

You can redefine the functions of the keys in the keypad and several of the

CONTROL and keyboard keys with the line command DEFINE KEY or the
keypad command €TRUK). You can redefine keys for the current editing session,
or you can put the new key definitions in your start-up command file.

2.6.6

Defining Macros

You can group several line-editing commands together and use them as one
unit, or macro. To do so, give the DEFINE MACRO command and enter the

commands in the proper sequence. Later, EDT will execute that series of
commands whenever you type the name of the buffer containing the macro.

You can define a macro for the current editing session only, or you can put it

In your start-up command file.

2-20

Using an Editor:

EDT

2.7 For More Information
There are several sources of information about EDT. Both the line and keypad
- HELP facilities provide a quick reference for EDT commands. EDTCAI the

computer-aided course on EDT, is especially good for users unfamiliar with

text editors. The EDT Editor Reference Card provides a summary of EDT’s
keypad editing features, and the EDT Editor Manual contains an extensive
description of how to use EDT, including a complete list of EDT commands,
their parameters, and qualifiers.

For information about SOS, see the VAX-11 SOS Text Editing Reference

Manual; for information about batch editors SUM and SUMSLP, see the

/fl—-\\‘

VAX-11 Utilities Reference Manual.

Using an Editor:

EDT

2-21

Chapter 3

‘

Commands to Manipulate Files
The previous chapter described how to create and edit files using the EDT
editor. This chapter explains how to use DCL commands to manipulate files:
how to identify, create, delete, and purge files; how to create and list directories; and how to copy and rename files.

3.1 Identifying Files
A complete file specification contains all the information the system needs to
locate and identify a file. A complete file specification has the format:
an

wee

eeu

nae

11}

ase

sow

a0 ofs

see

e .. *

"I.. l‘

sne .o

sea Y 1y

ofe

.. LIy sea

’x

1T .an

The punctuation marks (colons, brackets, period, semicolon) are required
syntax that separate the various components of the file specification.

3.1.1

Nodes

When computer systems are linked together to form a network, each system in

the network is called a node, and is identified within the network by a unique
node name. Your system may or may not be part of a larger network. To find
out, type SHOW NETWORK. If your system is part of a network, you
will see a list of node names displayed on your screen. (The node labeled
“LOCAL” is your own system’s node name.) If your system is not a part of a
network, a message indicating that no network is available will appear.

If your system is a network node, you may be able to gain access to a file
located at another node on the network by adding a node specification to the
first part of the file specification. (This specification will allow you access to
the file only if the user owning the file has permitted other users access to it.)
If you do not specify a node, the system assumes by default that the file
belongs to your own, or local, node. See the DECnet-VAX documentation for
an explanation of gaining access to files across a network.

3-1

3.1.2

Devices

The second part of a file specification, the device name, identifies the physical
device on which a file is stored. A device name has three parts:
e The device type, which identifies the hardware device (For example, an
RPO06 disk is DB and a TE16 magnetic tape is MT.)
e A controller designator, which identifies the hardware controller to which
the device is attached

e The unit number, which uniquely identifies a device on a particular controller

Some examples of device names are:
Name

Device

DBA2

RPO06 disk on controller A, unit 2

MTAO

TE16 magnetic tape on controller A, unit 0

TTB3

Terminal on controller B, unit 3

If you omit a device name from a file specification, the system supplies the
default value; that is, it assumes the file is on the disk assigned you when the
system manager set up your account. This disk is your default disk.
3.1.3

Directories and Subdirectories

Since a disk can contain files belonging to many different users, each user of a
given disk has a directory that catalogs all the files belonging to him on that
device.

As with the default disk, if you do not specify another directory, or if you do
not specify any directory, the system applies the default; it assumes that the
files to which you refer are cataloged in your default directory. You can find
out what your current default disk and directory are by issuing a SHOW
DEFAULT command:
%

show

default @D

DEAZ:[MALCOLMI

This response from the SHOW DEFAULT command indicates that the user’s
default device is DBA2 and the default directory is [MALCOLM].
You can gain access to files in other directories (including directories that
catalog files belonging to other users) by specifying the directory name in a

file specification. For example, to display on your terminal the contents of a
file named CONTENTS.DAT belonging to a user whose directory is [JONES],
issue the TYPE command as shown below:
%

3-2

tvype

[Joneslcontents.dat@E

Commands to Manipulate Files

Note that the file specification does not include a device name. For this
command to execute successfully, the directory [JONES] must be on your
default disk device. This is because the system always applies a default when
you omit a device name. If user JONES’s directory is on the disk DBB2 you
would issue the TYPE command as:
$

tvype

dbb2:[Joneslcontents.dat
@

In both of these examples, it is assumed that the user Jones has given other
users access to files in the directory. You can explicitly allow or restrict access
to your own files, either generally or on a file-by-file basis, with the SET
PROTECTION command. See the VAX/VMS Command Language User’s
Guide for information about directory and file protection and for a description
of the SET PROTECTION command.

Files can also be cataloged in subdirectories. A subdirectory is a file (cataloged in a higher directory) that contains additional files. A subdirectory
name is formed by concatenating its name to the name of the directory that
lists it. For example:
$

tvre

[Jones.datafileslmemo.sum@E

This TYPE command requests a display of the file MEMO.SUM that is
cataloged in the subdirectory [JONES.DATAFILES]. The subdirectory file
name is DATAFILES.DIR, and is cataloged in the directory [JONES].
Subdirectories are described in more detail in Section 3.8.
3.1.4

File Names, Types, and Versions

By taking advantage of your default node, disk, and directory, you can identify a file uniquely by specifying only its file name and file type in the format:
filename:tvre

The file name can have from one to nine characters chosen from the letters A
through Z and the numbers 0 through 9. When you create files, you can give
them any names that are meaningful to you.

The file type can be from zero to three characters, and must be preceded by a
period; again, you can choose any of the letters A through Z or the numbers 0
through 9 for the file type. However, the file type usually describes more
specifically the kind of data in the file, and the system recognizes several
default file types used for special purposes. For example, each high-level
language has a default file type for source programs. (See Section 4.1 for a
table of these file types.)

Commands to Manipulate Files

3-3

Among the other default file types are:
File
Type

Use

DAT

Data file

EDT

Start-up command file for EDT editor

EXE

Executable program image file

JOU

Journal file used by the EDT editor

LIS

Output listing file

MAI

Mail message file

OBJ

Object module file output from a compiler or assembler

In addition to a file name and type, every file has a version number that the
system assigns to a file when the file is created or revised. When you initially
create a file, the system assigns it a version number of 1. Subsequently, when
you edit a file or create additional versions of it, the version number is automatically increased by one.

You rarely need to specify the version number with a file specification. The
system assumes default values for version numbers, as it does with devices,
directories, and file types. Version number defaults are determined as follows:

For an input file, the system uses the highest existing version number of
the file.

For an output file, the system adds 1 to the highest existing version
number.

When you specify a version number in a file specification, you can precede the
version number with either a semicolon (;) or a period (.).
3.1.5

Wild Card Characters

A wild card character is a symbol that you can use with many DCL commands to apply the command to several files at once, rather than specifying

each file individually. Two wild card characters, the asterisk (*) and the
percent sign ( % ) can be used in specifications of a directory, file name, and
file type. The asterisk can also be used to specify version numbers.

For example, you can specify all versions of a file by using an asterisk in place
of the version number in the file specification. If, for example, you want to
print all versions of the file TESTFILE.DAT without specifying each version
number separately, type:

3-4

Commands to Manipulate Files

If there were no wild card character in the above example, the PRINT command by default would apply only to the most recent version of the file
TESTFILE.DAT. The following command prints all versions of all files in the
current directory with the file type of DAT:
%

*.dati*

To print all versions of all files in the directory with the file name of TEST,
type:
%

test.®i#%

The percent sign allows you to specify all files containing any single character
in the position that the percent sign occupies in the file specification. For
example, to print the latest version of several files with a file type of TX'T and

a file name that begins with CHAP but ends in a series of different numbers,
as in CHAP1.TXT, CHAP2.TXT, and CHAP3.TXT, type:
%

chapr%.txt

Note that in this example the percent sign specifies only one character. Therefore, the print command above would not affect a file named CHAP.TXT or
CHAPIX.TXT.,

3.2 Creating Files
Chapter 2 explains how to create a file by using the EDIT command to invoke
an editor. You can also use the CREATE command to make a new file.
Specify the file name as a parameter. You can insert text immediately, terminating the insertion with CTRLZ).
%

create

This

mvfile.dat
the

only

line.

CWUZ

Unlike the EDIT command, the CREATE command does not modify an
existing file.

3.3 Deleting Files
Quite often, as you develop and revise programs you end up with many versions. Since these files take up space on your disk, you may want to delete
versions of files that you no longer need.

The DELETE command deletes specific files. When you use the DELETE
command, you must specify a file name, file type, and version number (having to specify a version number provides some protection against accidental

Commands to Manipulate Files

— 3-5

deletion). However, any of these file components can be specified as a wild
card character. You can also enter more than one file specification on a command line separating the file specifications with commas. Some examples of
the DELETE command are:

Command

Result

% delete averade.obJdil

Deletes the file named AVERAGE.OBJ;1

$ delete *,1isi#

Deletes all files with file types of LIS

(thus, this command deletes all versions of

all program listings)

$ delete a.datil:a.dats?

Deletes the first two versions of the same
data file

3.4 Purging Files
You may want to clean up your directory by getting rid of all early versions of
particular files. If you have many versions of a file, naming them all in the

DELETE command would be tedious.

The PURGE command allows you to delete all but the most recent version of
a file; therefore, no version number is required by the PURGE command. For
example:
$

purde

averade.for@T

This command deletes all files named AVERAGE.FOR except the file with
the highest version number.

The /KEEP qualifier of the PURGE command allows you to specify that you
want to keep more than one version of a file. For example:

This command deletes all but the two most recent versions of the file
TEST.DAT.

3.5 Displaying Files at Your Terminal
The TYPE command displays a file at your terminal. For example:
$

tvype

This
a

file

the

EDT

test.datRED

the

first

created

line

with

editor.

While a file is being displayed, you can interrupt the output by using any of
the following CTRL key combinations:

suspends the terminal display of the file and the processing of the
command. To resume display, press €RUQ. The interrupted command displays lines beginning at the point at which processing was interrupted.

3-6

Commands to Manipulate Files

interrupts command processing. The system then prompts you

to enter another command.

3.6 Printing Files

When you use the PRINT command to obtain a printed copy of a file, the
system cannot always print the file immediately, since there may be only one
or two line printers for all users to share. The system enters the name of the
file you want to print in a queue, and prints the file at the first opportunity.
A printed file is preceded by a header page describing the file so you can
identify your own listing. For example, if you issue the following command,
the header page will show your user name and the file name, type, and version
number of the file.
%

Job

]

dbhZ:LJone

entered

210

sueue

RET

SYSEPRINT

When you use the PRINT command, the system responds with a message
indicating the job number it assigned to the print job.
The PRINT command also has qualifiers that allow you to control the number
of copies of the file to print, the type of forms to print the file on, and so on.
More information on these qualifiers can be found in the VAX/VMS Command Language User’s Guide.

3.7 Listing Files in a Directory
The DIRECTORY command lists the names of files in a particular directory.
If you type the DIRECTORY command with no parameters or qualifiers, the
command displays the files listed in your default directory on the terminal.
For example:
&

RET

11 Ter

DIRECTORY DBAZ:[MALCOLMI@

AVERAGE.EXE3?
AVERAGE.OBJ3Z
Total

AVERAGE.FORIZ
AVERAGE.EXE3il
AVERAGE.DBJ;1@

AVERAGE.FORG1

files.©

The following notes are keyed to this sample output of the DIRECTORY
command:

@ The disk and directory name.

@® The file names, file types, and version numbers of each file in the directory.

® The total number of files in the directory.

When you give the DIRECTORY command, you can provide one or more file
specifications to obtain a listing about only particular files. For example, to

Commands to Manipulate Files

3-7

find out how many versions of the file AVERAGE.FOR currently exist, issue
the DIRECTORY command as follows:
%

DIRECTORY

AVERAGE . FOR 32
Total

AVERAGE
. FOR 31

files.

3.8 Creating Subdirectories
Normally, the system manager provides each system user with one directory
in which to maintain files. If you are a frequent user of the system and work on
several applications, you may find it convenient to create several subdirectories, cataloging them in your main directory. You can create subdirectories in
any directory in which you can create files.

The CREATE/DIRECTORY command creates a subdirectory. For example:
$

create/directory

[malcolm.testfiles]@E

This command creates the subdirectory file TESTFILES.DIR in the directory
IMALCOLM]. You can specify the subdirectory name, [MALCOLM.TESTFILES], in commands or programs.

3.9 Changing Your Default Directory
To establish another directory or subdirectory as your default directory, use

the SET DEFAULT command. For instance, you could create a new file in
the subdirectory [MALCOLM.TESTFILES] by changing your default directory and then creating the file with the EDIT command:
$

set

edit

Input

default

[malcolm.testfiles]@ED

newfile.txt
BED

file

does

not

exist

[EOB]
#

The
new
file
will
be
cataloged
1in
the
subdirectory
IMALCOLM.TESTFILES]. (You could also do this by specifying the subdirectory as part of the file specification when you use the EDIT command.)
You can also use the SET DEFAULT command to change your default disk.
For example:
$

3-8

set

default

dbb2:
@S

Commands to Manipulate Files

After you issue this command, the system uses the disk DBB2 as the default
disk for all files that you access or create.

You can change your default disk and directory as often as is convenient. The
changes you make with the SET DEFAULT command remain in effect until

you either issue another SET DEFAULT command or log out.

3.10 Copying Files
The COPY command makes copies of files. You can use it to make copies of
files in your default directory, to copy files from one directory to another
directory, to copy files from other devices, or to create files consisting of more
than one input file.

When you issue the COPY command, you specify first the name(s) of the

input file(s) you want to copy, then the name of the output file. For example,

the following COPY command copies the contents of the file PAYROLL.TST
to a file named PAYROLL.OLD.

If a file named PAYROLL.OLD exists, a new version of that file is created
with a higher version number.

You could copy a file from the directory [MALCOLM] to the subdirectory
IMALCOLM.TESTFILES], and give it the new name, OLDFILE.DAT.
$

copy

newfile.dat

[malcolm.testfilesloldfile.dat@®E

When you copy files from devices other than your default disk, you must

specify the device name in the COPY command. For example, the following
COPY command copies a file from your default directory onto an RK06 disk.

Note that the output file specification did not include a file name or file type;
the COPY command uses the same directory, file name, and file type as the
input file, by default.

Before you can copy any files to or from devices other than system disks, you
must gain access to these devices. You do this by:

e Mounting the volume, with the MOUNT command.

e Ensuring that the volume has a directory for cataloging the file. If no directory exists, use the CREATE command to create one.

Note that the VAX/VMS operating system protects access to volumes that
individuals maintain for private purposes, as well as access to system volumes. For details on the commands and procedures necessary to prepare and
use disks and tapes, see the VAX/VMS Command Language User’s Guide.

Commands to Manipulate Files

3-9

3.11

Renaming Files
The RENAME command changes the identification of one or more files. For

example, the following command changes the name of the most recent version
of the file PAYROLL.DAT to TEST.OLD.
%

rename

pavroll.dat

is’x.i.v,nis{@"T

You can use the RENAME command to move a file from one directory to
another. For example, the following command moves test.old from the direc-

tory IMALCOLM] to the subdirectory IMALCOLM.TESTFILES]:
t

rename

[malcolmltest.old

[malcolm.testfile:

You can use wild card characters if you want to change a number of files that

have either a common file name or file type. For example:
k3

rename

pPavYrao

¥ 5 ¥

Emalealim.teastfilea

1% ., % 7% [RET

This RENAME command changes the directory name for all versions of all
files that have file names of PAYROLL. The files are now cataloged in the
subdirectory [MALCOLM.TESTFILES].

3.12 For More Information
The VAX/VMS Command Language User’s Guide describes in more detail
the commands presented here. Part II of that manual lists all the commands

in alphabetical order and includes descriptions of parameters and qualifiers,
as well as giving additional examples of each command.

Remember, too, that while you are using the terminal, you can use the HELP
command to receive on-the-spot assistance if you cannot remember a parameter or qualifier. Or, you can let the system prompt you for command parame-

ters, if you cannot remember the order in which you have to enter them.

See the DECnet-VAX documentation for further explanation of networks and
node specifications.

3-10

Commands to Manipulate Files

Chapter 4

Program Development
Four steps are required to develop a program:

e Creating the source program file

e Compiling or assembling the source program file to produce an object
module file

e Linking the object module file to produce an'image
e Executing and debugging the program

4.1 Creating the Program

In order to run your program, you must first create a file of the program source

statements. The default file type corresponds to the language in which the
program is written. For instance, it your program is written in VAX-11
BASIC, its file type default is BAS. The following are default file types for
source program files written in VAX-11 languages:
File

Type

Contents

BAS

Input source file for the VAX-11 BASIC compiler
Input source file for the VAX-11 BLISS-32 compiler
Input source file for the VAX-11 C compiler

B32
C

COB

COR

FOR

MAR
PAS
PLI

Input source file for the VAX-11 COBOL compiler
Input source file for the VAX-11 COBOL-74 compiler

Input source file for the VAX-11 CORAL-66 compiler
Input source file for the VAX-11 FORTRAN compiler

Input source file for the VAX-11 MACRO assembler
Input source file for the VAX-11 PASCAL compiler
Input source file for the VAX-11 PL/I compiler

4-1

4.2 Compiling or Assembling the Program
To prepare your source program for execution by the computer, a language
processor must translate it into a format that the computer can read. That is,

your program must be either assembled or compiled, depending upon whether
it is written in assembly language or in one of the high-level languages sup-

ported by VAX/VMS.
Both compilers and assemblers are programs that translate source programs

into binary machine code that can be interpreted by the computer. An assembly language is usually designed for a specific computer, and it generally
assembles line for line into machine code. Most high-level languages, on the
other hand, are designed to be universal, and usually compile one line of

source code into several lines of machine code. If your source program is
written in assembly language (in this case, VAX-11 MACRO), you invoke the

VAX-11 MACRO assembler to translate it. If it is written in a high-level
language (such as BASIC, C, COBOL, FORTRAN, PASCAL, or PL/I), you
invoke the appropriate VAX-11 language compilers to compile the program.
There is a DCL: command to invoke each language processor:
Command

Invokes

BASIC

VAX-11 BASIC compiler

BLISS

VAX-11 BLISS-32 compiler

CcC

VAX-11 C compiler

COBOL

VAX-11 COBOL compiler

COBOL/C74

VAX-11 COBOL-74 compiler

CORAL

VAX-11 CORAL-66 compiler

FORTRAN

VAX-11 FORTRAN compiler

MACRO

VAX-11 MACRO assembler

PASCAL

VAX-11 PASCAL compiler

PLI

VAX-11 PL/I compiler

Each of these commands invokes a compiler (or assembler) to translate the
source program named in the file that follows the command. Although each

command differs slightly in its parameters and qualifiers, the command format is essentially the same:
%

basic

mvfile

This command invokes the BASIC compiler to translate the file MYFILE into
machine code, writing it to an output file called an object module. Since no

file type is specified, the compiler assumes the default file type of BAS.

4-2

Program Development

4.3 Linking the Object Module
An object module is not, in itself, executable; generally, it contains references
to other programs or routines that must be combined with the object module
before it can be executed. It is the function of the linker to do the combining.
The LINK command invokes the VAX-11 Linker. The linker searches system
libraries to resolve references to routines or symbols that are not defined
within the object modules it is linking. You can request the linker to include
more than one object module as input, or specify your own libraries of object
modules for it to search. The format of the LINK command is:
¢

link

myfile

Since no file type is specified, the linker supplies a default file type of OBJ for

object modules.

The linker creates an image, which is a file containing your program in an
executable format.

4.4 Executing the Program

The RUN command executes an image, that is, it places the image created by
the linker into memory so that it can run. The format of the RUN command
is:
&

run

myfile

Since no file type is specified, the RUN command uses the default file type of
EXE for executable images.

The first time you run a program, it may not execute properly; if it has a bug,
or programming error, you may be able to determine the cause of the error by
examining the output from the program. When you have determined the
cause of the error, you can correct your source program and repeat the compile, link, and run steps to test the result. Figure 4-1 illustrates these steps in
program development.

The remaining sections of this chapter illustrate the steps of program develop-

ment with two sample programs: a MACRO example for assembly language
users and a FORTRAN example for high-level language users. These sections
describe the input and output files used in each step and the naming conventions for the files. They also present optional command qualifiers you can use
to create additional output files, including program listings. If you have access
to a terminal, you can create the programs and issue the commands that are
described.

At the end of the chapter, Section 4.7 lists additional documentation with
further information about the tools VAX/VMS provides, for program development. For information about a particular VAX-11 language, see the document set for that language.

Program Development — 4-3

Use the editor to create
a disk file containing your
source program statements.

Specify the name of this file

Source
program

when you invoke the compiler
or assembler.

J
Commands invoke language
processors that check syntax,
create object modules, and
if requested, generate

Compiler
or

Assembler

program listings.

If a processor signals any
errors, use the editor to

Errors?

yes

Correct the
source program

correct the source program.

The linker searches the system
libraries to resolve references

in the object module and create
an executable image. Optionally,

Link the

you can specify private libraries

object module

to search, and request the linker
to create a storage map of
your program.

The linker issues diagnostic
messages if an object module

refers to subroutines or symbols
that are not available or

undefined.

[f the linker cannot

locate a subroutine, you must

Errors?

reissue the L/NK command
specifying the modules or

libraries to include. If a
symbol is undefined, you may
need to correct the source program.

The RUN command executes a
program image. While your
program is running, the system

may detect errors and issue
messages. To determine if your

Run the
executable
image

program is error-free, check
its output.

If there is a bug in your

program, determine the cause
of the error and correct the

Bugs?

yes

source program.

SUCCESS
ZK-763-82

Figure 4-1:

Program Development

Steps in Program Development

4.5 A FORTRAN Program

The steps required to prepare a VAX-11 FORTRAN' program to run on
VAX/VMS are illustrated in Figure 4-2. Figure 4-2 also notes the default file
types used by the FORTRAN, LINK, and RUN commands. For any of these
commands, you can specify an explicit file type to override the defaults when
you name an input or output file.

INPUT/OUTPUT FILES

COMMANDS

$ EDIT/EDT AVERAGE.FOR
Use the file type of FOR to
indicate the file contains a

i
Z|

Create'a

source program

VAX-11 FORTRAN

AVERAGE.FOR

program.

$ FORTRAN AVERAGE
The FORTRAN command
assumes the file type of an

Compile the

input file is FOR.

source program

(If you use the /LIST

AVERAGE.OBJ

(AVERAGE.LIS)
libraries

qualifier, the compiler
creates a listing file.)

$ LINK AVERAGE

The L/NK command assumes
file
an input t fil
file t ype of fani
itshe eOB:Je

Ll Tia

object module

)

AVERAGE.EXE
(AVERAGE.MAP)

(If you use the /MAP qualifier,
the linker creates a map file.)

$ RUN AVERAGE

Run the
exe.cutable

The RUN command assumes
the file type of an image is

image

EXE.

ZK-764-82

Figure 4-2:
4.5.1

Commands for FORTRAN Program Development

Creating the Source Program

Use the editor (described in Chapter 2) to create a source program interactively. For example, to create the FORTRAN program called AVERAGE,
issue the EDIT command as follows:
Input

file

does

not

exist

[EOB]
¥*

1. The VAX-11 FORTRAN compiler is referred to simply as FORTRAN throughout this

manual.

Program Development — 4-5

The asterisk prompt indicates that EDT is ready to accept a line-editing

command.
The program AVERAGE is shown below. When you type the input statements, you can use the

key to align the statement and comments col-

umns. Tabs are set at every eight character positions. The EDT line editor
assigns line numbers to help you locate text; the line numbers are not part of
the file, however. (To display the line numbers, give the TYPE WHOLE
command after the asterisk prompt.)
1

PROGRAM

AVERAGE

COMPUTES

THE

AVYERAGE

TERMINATE

THE

NUMBERS

PROGRAM:

ENTER

ENTERED

TERMINAL

93993

TOTAL

INITIALIZE

ACCUMULATOR

INITIALIZE

COUNTER

PROMPT

WRITE

(G,10)

ENTER

NUMBER

11
12

FORMAT
READ

(‘

ENTER

(5,20)

NUMBER:

END

WITH
|

9939
°)

READ

NUMBER

9999

MEANS

COMPUTE

FROM

TERMINAL

FORMAT
(K

I10

+EQ.,

TOTAL

GOTO

S
COMPUTE

9999)

TOTAL

GOTOD

INPUT

TOTAL

WITH

NUMBER

19
20

NOW,

TIMES

AVERAG

WRITE

THROUGH
=

AVERAGE
THE

DIVIDING

TOTAL

THE

HUMBER,
OF

LOOP

TOTAL/N

(G.:50)

AVERAG

DISPLAY

THE

RESULT

FORMAT

(°

AVERAGE

“F10.,2)

27
28

STOP

END

The program AVERAGE reads and writes lines to the current input and

output devices; it prompts the user to enter numbers and then computes the
average of the numbers entered. This program purposely has a syntax error

and a bug, so you can get an idea of how to use VAX/VMS to correct programming errors.

4.5.2

The FORTRAN Command

When you enter the FORTRAN command from the terminal, the FORTRAN
compiler, by default:

* Produces an object module that has the same file name as the source file
and a file type of OBJ

e Uses FORTRAN compiler defaults when it creates the output files (qualifiers on the FORTRAN command can override these defaults)

To compile the source program AVERAGE, issue the command:
%

4-6

foTt

ran

Program Development

\uUerade
RET

Since the FORTRAN command assumes a file type of FOR, you need not
specify the file type when you name the file to be compiled.
If the compilation is successful — that is, if the compiler did not detect any
errors — the system displays a prompt for the next command:
&

If there are any errors, the FORTRAN compiler displays information on the
terminal. If you entered the source program AVERAGE exactly as it appeared
above, then you received the message:

YFORT-F-ERROR 33 Missing orerator
[FORMAT 11 in
YFORT-F-ENDNOOBJ:

completed
obhiect

delimiter

module AVERAGE at line B2
DBZ:[MALCOLMIAVERAGE.FORGL»
with

svmbol

diadnostic-

deleted

This message indicates that the FORMAT statement was incorrectly coded;
you must put parentheses around the format specification.

To correct the error, edit the source file. First, invoke EDT:
Prodram

#replace

line

AVERAGE

135

deleted

FORMAT

(I103CmRUZ

The REPLACE command deletes the line specified and inserts the line or
lines you type. If you had more than one error in your source file, correct these
errors, too.

When you are satisfied with the changes, use the EXIT command to write the

E
.FORIE
DEAZ: [MALCOLMIAVERAG

lin

t
*exi@ET

]

updated file onto disk:

Notice that EDT has created a new version of the file AVERAGE.FOR.
Now you can recompile the program:
¢

fortran

averade(®E

The FORTRAN command always uses, by default, the version of the file with
the highest version number. If the program compiles successfully this time,
you can go on to the next step. Otherwise, repeat the procedure of correcting
the source file and compiling it.

Program Development

4-7

When you compile a source program, use the /LIST qualifier on the FORTRAN command to request the compiler to create a program listing. For
example:

The FORTRAN compiler creates, in addition to an object module, a file
named AVERAGE.LIS. To obtain a printed copy of the program, use the

PRINT command as shown below:
$

averade(RET

The PRINT command uses the default file type of LIS.

4.5.3

Linking the Object Module

To link the program AVERAGE, issue the LINK command as follows:
¢

link

averade®e

This LINK command creates a file named AVERAGE.EXE, which is an

executable program image. The linker automatically includes in the execut-

able image any library routines that the compiler requested for input/output
handling, error routines, and so on.

4.5.4

Running the Program

To execute the program AVERAGE, use the RUN command. When you issue
the RUN command, you provide the name of an executable image. By default, the RUN command assumes a file type of EXE. Thus, to run the
program AVERAGE, type the RUN command as follows:

AVERAGE is interactive: it prompts you to continue entering numbers and it
keeps a cumulative sum of the numbers you enter. When you enter 9999, it

computes the average of all the numbers you entered. A typical run of this

END

HITH

i}
5]

MUMBER:

END

HITH

9¢

NUMBER:

END

HITH

939%

MUMBER:

EMD

WHITH

MUMBER:

in}

ENTER

program might appear as follows:

aa]

is]

EMTER

33 @ET

jin}

i8]

48]

]

ENTER

55 ®RET

ENMTER
9999 @eT

AVERAGE

FORTRAM

STOP

4-8

Program Development

48,50

]

99 RET

As you can see, the program is not computing the average correctly. By looking at the program listing, you can see that the error occurs because the loop
counter (N) is incremented a final time when you enter 9999 to terminate
entering numbers. The value N must be decremented by 1.

To correct the error, edit the source file again:
%

averade.for®E

edit

Frodgram

Auverade

#CSubhstitute\TOTAL/NATotals/iMN-13%y
TOTAL/(RM-11

AVERAG
1

Z3@E

Substitution

GE
.FORSE
DBAZ: [MALCOLMIAVERA

lines

The SUBSTITUTE command deletes the first string, TOTAL/N, and inserts
the second, TOTAL/(N-1), in the line specified. The EXIT command writes a
new version of the file onto disk.

Now, repeat the compile, link, and run steps:
$

fortran

averade(®ET

% link averade(®D
% run averade(@E
ERNTER NUMBER: END

WITH

2393

33 RET

MUMBER:

END

WITH

2983

NUMBER:

ERND

WITH

Z983

MUMBER:

END

WITH

2999

AVERAGE

GE.00

FORTRAN

STOP

ENTER
565 RET

EMNTER
1 9 RET)
EMTER
9995 REeT

In this example, the bug was easy to spot; this is not usually the case, however, and you may need to investigate a program further to debug it.
4.5.5

Debugging the Program

The VAX/VMS operating system has a debugger, a program that permits you
to debug your programs interactively. When you want to use the debugger,
you have to compile the source program with the /DEBUG and /NOOPTIMIZE qualifiers, as follows:
”

fortran/debud/nooprtimize

averadeET

These qualifiers make the later use of the debugger program possible with this
FORTRAN program. When the compilation completes, use the /DEBUG
qualifier when you link the object module:
$

link/debud

averadeRE

Program Development

4-9

Now, when you use the RUN command to execute the program image AVERto stop the execution of the program at a particular statement and examine or
modify a variable.

For information on how to use the debugger, see the VAX-11

AGE.EXE, the debugger takes control, and you can use debugging commands

FORTRAN

User’s Guide.

4.6

A MACRO Program
The steps required to prepare a VAX-11 MACRO!® program to run under
VAX/VMS are illustrated in Figure 4-3. Figure 4-3 also notes the default file
types used by the MACRO, LINK, and RUN commands. For any of these
commands, you can specify an explicit file type to override the default when

you name an input or output file.

COMMANDS

INPUT/OUTPUT FILES

$ EDIT/EDT NAME.MAR

Use the file type of MAR to
indicate the source file

§
Create the

contains a VAX-11 MACRO

program.

NAME.MAR

> \_j

source program

N~
]

\_j

libraries

$ MACRO NAME
The MACRO command

assumes the file type of an

input file is MAR.

Assemble the
source program

If you use the /LIST

N
2

NAME.OBJ
(NAME.LIS)

N—

qualifier, the assembler

creates a listing file.

libraries

—

$ LINK NAME
The L/INK command assumes

's 08J.

O
Link the

. object module

the linker creates a map file.

If you use the /MAP qualifier,

$ RUN NAME

The RUN command assumes
:

the file type of an image is
EXE.

/ N—

‘

NAME.EXE

)

(NAME.MAP)

Run the

executable

]

image

ZK-765-82

Figure 4-3:

Commands for MACRO Program Development

1. The VAX-11 MACRO assembler is referred to simply as MACRO throughout this manual.

4-10

Program Development

//flm\».

jche file type of an input file

Creating the Source Program

4.6.1

Use the editor (described in Chapter 2) to create a source program interactively. For example, to create the MACRO program called NAME, issue the
EDIT command as follows:
RET
mame.mar
file does not

$odit
Input

exist

LEDOB]

*¥Tnsert

(ET

EDT is now ready to accept input lines.

The program NAME is shown below. When you type the input statements,

key to align the operand and comments columns. Tabs are
you can use the
set at every eight character positions. The EDT line editor assigns line numbers to help you locate text; the line numbers are not part of the file, however.
(To see the line numbers, give the TYPE WHOLE command after the asterisk
prompt.)

The program uses VAX-11 RMS to read and write lines to the current terminal; it issues a prompting message asking for the user’s name and redisplays

whatever is entered in response. This program purposely has a syntax error

and a bug, so you get an idea of how to use VAX/VMS to correct programming

errors.

+TITLE
+IDENT

1
2

.PSECT

3
)

9
G

NAME
701/

RWDATAWRT NOEXE

i DEFINE CONTROL BLOCKS FOR TERMINAL INPUT AND OUTPUT

TRMFAB: $FAB

T 3iFAB FOR TERMINAL
FAC=<GET ,PUT>
yRAT=CR INPU
FNM=SYS$
-

TRMRAB:

$RAB

FAB=TRMFAB sUBF=BUFFER +USZ=BUFSIZ,
ROP=PMT, PBF=PMSG1., PSZ=P1SIZ

BUFFER:

BLKB

132

i INPUT READ BUFFER

PMSG1:
P1SIZ=

+WASCII
+-PMSG1

/ENTER YOUR NAME:

5 PROMPT MESSAGE
i MESSAGE SIZE

18
19

OUTMSG:
OUTBUF:

+ASCII
BLKB

/HELLO, YOUR NAME IS/
30

5 OUTPUT MESSAGE
;7 MOVE NAME HERE

MSGSIZ:

JBLKL

i ADD LENGTHS HERE

9
10
11

12
13
14

15
16
17

26
27
28
29
30

31
3z
33

34
35

36
37
38

BUFSIZ=

OUTLEN:

.-BUFFER

LONG

+PSECT

OUTBUF-0OUTHMSG

yEXE sNOWRT
NAME

i BUFFER LENGTH

VENTRY

BEGIN,O

i ENTRY MASK

$0PEN
BLBC
$CONNECT
BLBC

FAB=TRMFAB
ROJERROR
RAB=TRMRAB
ROVERROR

i
i
;7
i

$GET
BLBC

RAB=TRMRAB
ROERROR

i ISSUE PROMPT
i EXIT IF ERROR

OPEN TERMINAL FILE
EXIT IF ERROR
ESTABLISH RAB
EXIT IF ERROR

i MOVE NAME ENTERED INTO OUTPUT MESSAGE: AND FIX UP LENGTH
MOVC3
MOUVZMWL
ADDL

+OUTBUF
yBUFFER_RSZ
TRMRAB+RAB$W
TRMRAB+RAB$MW_RSZ +MSGSIZ
MSGSIZ »OUTLEN

Program Development

4-11

AFTER

CONSTRUCTING

OUTPUT

MESSAGE,

OUTPUT

az2

MOVAL

OUTMSG»TRMRAB+RAB$L
_RBF i UPDATE

RAB:

ADDRESS

MOUW

MSGSIZ »TRMRAB+RAB$W_RSZi

RAB:

SIZE

SPUT

RAB=TRMRAB

BLBC

ROJERROR

UPDATE
EXIT

ERROR

ALL

DONE,

THE

FILE

$CLOSE

FAB=TRMFAB

50
51

ERROR:

RET

+END

4.6.2

BEGIN

The MACRO Command

When you enter the MACRO command, the MACRO assembler, by default:
1.

Produces an object module that has the same file name as the source file
and a file type of OBJ

Uses MACRO assembler defaults when it creates output files (qualifiers
on the command line can override these defaults)

Searches the system macro library for definitions for system macros, such
as the VAX-11 RMS macros $FAB and $RAB used in the sample program
NAME.MAR

To assemble the source program NAME, issue the command:
%

macroslist

nameRET

Since the MACRO command assumes a file type of MAR, you need not

specify the file type when you name the file to be assembled. The /LIST
qualifier indicates that you want a listing of the program; if there are any
errors in the assembly, you may need the listing to determine what the errors
are.

If the assembly is successful — that is, if the assembler did not detect any
errors — the system displays a prompt for the next command:
S

If errors occur, a message is displayed at the terminal. If you entered the

source program NAME exactly as it appeared above, then you received an
error message:

AMACRO-E-UNTERMARG:
There

were

error:

Unterminated

ardument

warnings:

and

information

messades

lines:

L3011}

This message indicates that the ASCII string argument coded on line 15 is
incorrect; you must terminate the string with a slash (/) character.

4-12

Program Development

To correct the error, edit the source file. First, invoke EDT:
& edit

name.mar (RET
STITLE

HMAME

Now, use editor commands to locate the line and correct the error, as shown
below:
+REPLACE

deleted

line

The REPLACE command deletes the line (15) that was in error, and inserts
the line or lines you type in its place. If you had more than one error in your
source file, correct these errors, too.

When you are satisfied with the changes, use the exit command to write the
updated file onto disk:
sy 1t (RET
D

MARIE 54
47 : [MALCOLHMI.MAME

lines

Notice that EDT has created a new version of the file NAME.MAR.
Now, you can reassemble the program:
¢

macro/list

name@E

If the program assembles successfully this time, you can go on to the next
step. Otherwise, repeat the procedure of looking at the listing, correcting the
source file, and assembling it.

4.6.3

Linking the Object Module

To link the program NAME, issue the LINK command as follows:
&

link

name @

This LINK command creates a file named NAME.EXE, which is an execut-

able program image. The linker automatically includes in the executable
image any library procedures required by the VAX-11 RMS routines used.
4.6.4

Running the Program

To execute the program NAME, use the RUN command. When you issue the
RUN command, you provide the name of an executable image. By default,

Program Development

4-13

the RUN command assumes a file type of EXE. Thus, to run the program
NAME, type the RUN command as follows:
$

ruy

l].'l!*ffT

NAME is interactive: it prompts you to enter your name, then it creates an
output string from the string you entered and outputs it. A typical run of this

program might appear as follows:
ENTER

YOUR

NAME:OFTCKGE

HELLO
%

As you can see, the program is writing only the first 6 characters of the output
message. If you examine the listing, you can see that on line 43 the MOVW
instruction places the wrong length in the buffer size field of the RAB; it uses

the MSGSIZ field (that is, the length of the string you entered) rather than
the sum of the string you entered and the OUTMSG string.
To correct the error, edit the source file again:
&

edit

name:mar

1
¥Rerplace
1

line

RET

sTitle

Mame

deleted
MOWUE

OUTLEN:

TRMRAB+RABEW_RESZ3

UPDATE

RAB:51ZECHRUZ
a4

$PUT

RAB=TRHMRAE

*EHXTT
DEBAZ:[MALCOLMINAME. MARIZ

lines

Now, repeat the assembling, linking, and running:
$

macro

link

run

name RET
name RET

rame RET

ENTER

YOUR

HELLO:

YOUR

NAME:7"ORICK®ET
MNAME

YORICK

In this example, the bug was easy to spot; this is not always the case, however,
and you may need to investigate a program further to debug it.

4.6.5

Debugging the Program

The VAX/VMS operating system has a debugger, a program that permits you
to debug your programs interactively. When you want to use the debugger,

you can assemble the source program with the /ENABLE=DEBUG qualifier,

as follows:
¢

4-14

macro/enable=debud

Program Development

name RET

This qualifier requests the assembler to include, in the object module, special
information the debugger can use. When you link the object module you must
specify the /DEBUG qualifier to link the debugger program with your program. For example:
$

link/debud

name @D

Now when you use the RUN command to execute the program image
NAME.EXE, the debugger takes control, and you can use debugging commands to stop the execution of the program at a particular instruction and
examine or modify a variable.

For information on how to use the debugger, see the VAX-11 Symbolic

Debugger Reference Manual.

4.7 For More Information
The two program examples presented in this chapter show only the simplest
cases, using defaults for getting a program to run. VAX/VMS provides many
capabilities beyond those presented in these examples. Some of the
VAX/VMS manuals you may find useful are described below.
e The VAX/VMS Command Language User’s Guide contains reference information for all the commands that have been used in the examples in this
chapter.

e The VAX-11 Linker Reference Manual describes how to use the linker and
describes the options available to you when you link a program.

e The VAX-11 MACRO Language Reference Manual describes the features
and syntax of the VAX-11 MACRO language.

e The VAX-11 MACRO User’s Guide provides details on how to use the
VAX-11 MACRO assembler.

e The VAX-11 Symbolic Debugger Reference Manual describes the features
of the VAX-11 Symbolic Debugger.

e The VAX/VMS System Services Reference Manual presents additional programming capabilities through the VAX/VMS system services.
e The Introduction to VAX-11 Record Management Services describes the
file formats used in VAX/VMS, and the VAX-11 Record Management Services Reference Manual describes the macros that can be used to create,
read, and update files. The VAX-11 Record Management Services Ultilities
Reference Manual describes the VAX-11 RMS utilities that can be used to
design, create, load, and analyze files. The VAX-11 Record Management
Services Tuning Guide describes the concepts behind designing efficient
files and provides tutorial explanations of the utilities.

e The VAX-11 Common Run-Time Procedure Library contains procedures
that do such tasks as: perform common mathematical functions, manipulate character string data for input and output routines, and convert data

Program Development

4-15

from one type to another (e.g., changing a numeric ASCII string to a binary
value or a floating-point number to scientific notation). The VAX-11 RunTime Library Reference Manual contains descriptions of all general purpose
procedures in the Run-Time Library.
e The

VAX-11

Guide to

Creating Modular Library Procedures describes

methods for designing and coding procedures for insertion in an object module library or a shareable image.
Each of the VAX-11 languages is documented in a separate set of manuals

that generally includes a language reference manual and a user’s guide for
that particular language. For further information about a high-level language,

see the document set for that language.

Separate documentation exists for the following VAX-11 languages:
VAX-11 BASIC

VAX-11 BLISS

VAX-11 C
- VAX-11 COBOL

VAX-11 CORAL

VAX-11 FORTRAN
VAX-11 PASCAL

VAX-11 PL/I
See the VAX-11 Information Directory and Index for a list of the individual

manuals in the document sets for the VAX-11 languages.

4-16

Program Development

Chapter 5

Logical Names: Files for Program Input/Output
When you design programs to read and write data, you can code the programs
to read or write different files each time you run them. This is called device
and file independence.

In the VAX/VMS operating system, device independence 1s accomplished
through the use of logical names. When you code a program, you refer to an
input or output file according to the syntax requirements of the language you
are using. After the program is compiled and linked, but before you run it, you
can make the connection between the logical names you used in the program
and the actual files or devices you want to use when you run the program.

The ASSIGN command makes this connection: it establishes the correspondence between a logical name (that is, the name you use in the program) and
an equivalence name (that is, the actual file or device to use).

Figure 5-1 shows how 'logical names are used. The program FICA contains

OPEN, READ, and WRITE statements in a general form,; the program reads
from a file referred to by the logical name INFILE, and writes to a file referred

to by the logical name OUTFILE.

For different runs of the program, the ASSIGN command establishes different
equivalence names for INFILE and OUTFILE. In the first example, the program reads the file JANUARY.DAT from the device DBA1 and writes to the
file JANUARY.OUT onsthe same disk device. In the second example, it reads
" the file FEBRUARY.DAT from the device DBA2 and writes the file FEBRU-

EL
|

ARY.OUT to that device.

Terminal Display

Disk Input/Output Files

$ ASSIGN JANUARY.DAT INFILE~s$ SHOW DEFAULT

DBA1: [WELLADAY]

$ ASSIGN JANUARY.OUT OUTFILE

$ RUN FICA

The program, FICA.EXE contains |/0

DBA1

statements to open, read, and write

files referred to by the logical names
INFILE and OUTFILE:

OPEN ‘INFILE’, 'OUTFILE’

READ INFILE

WRITE OUTFILE

$ ASSIGN DBA2:FEBRUARY.DAT INFILE <=

$ ASSIGN DBA2:FEBRUARY.OUT OUTFILE——»

$ RUN FICA

%
DBA2
ZK-766-82

Figure 5-1:

5.1

Using Logical Names

Logical Names in Commands
The use of logical names is not restricted to application programs. Commands
that read or write files, such as COPY and TYPE, also accept logical names

A+

assidn

for a file specification. For example:

tvepe

The

[chucKklpersonnel.rec

myfile@D

myfile@ED

ASSIGN

command

equates

the

logical

name

MYFILE

the file

PERSONNEL.REC listed in the directory CHUCK. The TYPE command
requests the system to display this file on the terminal.

5-2

Logical Names:

Files for Program Input/Output

A logical name can also define only the first portion of a file specification. For

example:

dba?:ICmalcolm.testfiles]

assidn
run

test@ED

@D
test:memo

test:memo.lis@ED

The ASSIGN command equates the logical name TEST to the disk device
and directory DBA2:(MALCOLM.TESTFILES]. Subsequently, the RUN
command executes the program image MEMO.EXE cataloged in this subdirectory and the PRINT command prints another file. The system always
examines file specifications to see if the portion of the file specification that
precedes the colon (:) is a logical name; if it is (as in this example), the system
substitutes the equivalence name.

5.2 System Default Logical Names

When you log in to the system or submit a batch job, the system provides
several default logical names. These names are used by the command interpreter to read your commands and to print responses or error messages.

Among these logical names are:
Logical

Name

Use

EYS&INPUT

The default input stream from which the system reads commands and your programs read data

your terminal
Default interactive assignment:
the command procedure or
Default batch assignment:
batch stream

svesouTPUT

The default output stream to which the system writes re-

svssERrrOR

The default device to which the system writes all error and

sponses to commands and your programs write data
your terminal
Default interactive assignment:
batch job log file
Default batch assignment:
informational messages

your terminal
Default interactive assignment:
batch job log file
Default batch assignment:
5Y5$DISK

Your default disk device

Default assignment:

set in User Authorization File

You can use these logical names in programs. For example, if you code a
program to write a file to a device named SYS$OUTPUT, the output file goes
to your terminal if you execute the program interactively, or to the batch job
log file if you execute the program in a batch job.

Logical Names:

Files for Program Input/Output

5-3

You can also assign a logical name to another logical name. For example, to
test the program FICA shown in Figure 5-1, you could assign the logical name

OUTFILE to the logical name SYS$OUTPUT, as follows:
%

accidn

svs$output

outfile@T

Then, when FICA writes to the logical device OUTFILE, the output is directed to your terminal.
The

remaining

sections

this

chapter

contain

additional

language-specific examples of how logical names are used for program input
and output.

5.3 FORTRAN Input/Output
The VAX/VMS system supplies several default logical names for use with
FORTRAN programs. These logical names provide default devices for the

input/output statements indicated.
Logical
Name

Use

FORSREAD

Default input device read by READ statements that do not

specify a logical unit number

Default assignment:
FOR$PRINT

svssInpPUT

Default output device written by PRINT statements

Default assignment:
ForsACCERPT

Default input device read by ACCEPT statements

Default assignment:
FOR$TYPE

SOUTRUT

EIRNPLUT

Default output device written by TYPE statements

Default assignment:

syssouUTPUT

You do not need to take any special action to direct input or output when you
use these statements: the system translates the logical name SYS$INPUT or
SYS$OUTPUT and locates the current equivalence for that logical name.
However, when you want to have a program read or write data from or to a

device or file other than a default, or when you specify a logical unit number
on an input/output statement, you can take special action: you can assign an
equivalence name for the logical name.

5.3.1

Changing Default Logical Names

The ASSIGN command changes the equivalence for a logical name. For ex-

ample, suppose you have a FORTRAN program named STAT that uses both
TYPE and PRINT statements, as follows:
TYPE

PRIMT

5-4

Logical Names:

30:A:B.:C

100 :0:E:F

Files for Program Input/Output

To execute this program so that output from the PRINT statement goes to a

disk file rather than to the terminal, enter an ASSIGN command before
A

acsidn

running the program:

run

statdata.out

for$erint@D

stat @D

When STAT finishes execution, all output lines written by the PRINT statement are contained in the file STATDATA.OUT. The system uses your default disk device and directory to catalog the file.
5.3.2

Logical Names for Unit Numbers

The concept of logical names and default logical name assignments applies to
specifying input/output files by logical unit numbers. Each logical unit number has an associated default logical name, and each logical name has a

default equivalence name. These logical names and equivalence names are as

follows:

Logical

Default

Unit

Name

Equivalence

1
2
3
4
5
6

FOROO1
FORO002
FORO003
FORO004
FORO005
FORO006

FORO01.DAT
FORO002.DAT
FORO003.DAT
FOR004.DAT
SYSSINPUT
SYS$ouUTPUT

FOROnn

FOROi}n.DAT

For example, a program named BALANCE may contain the lines:

In the above example, 23 is a logical unit number. Before executing this
program, you can assign an equivalence name to the logical name FORO023 so
e

assign

that the READ statements read from a specific file, as follows:
run

libra.tst

forOQOZ3@D

bkalance®D

If you do not assign FOR023, the system uses the default equivalence name
FOR023.DAT. In either case, the system uses your current default disk and
directory.

Logical Names:

Files for Program Input/Output

5-5

5.3.3

Logical Names in OPEN Statements

If you code a program that uses an OPEN statement to define an input or
output file, you can specify the NAME parameter to give the file specification
for the file. In this case, the system does not use the default equivalence name

to locate a file for input or output, but uses the name specified.
A typical OPEN statement may look like the following:
OPEN

(UNMIT=19:HMAME= "HEATHER.S5T5 "}

When the program uses a READ statement to read the logical unit 19, it reads
the file WEATHER.STS. Note that the system supplies your current disk and
directory defaults to locate the file.

You can also specify a logical name with the NAME parameter. For example:
OPEN

(UNIT=Z0
:NAME= "0OUTFILE ‘)

Before you execute the program containing this OPEN statement, you can
assign an equivalence name to the logical name OUTFILE, as follows:
%

assidn

dmal:lscratchltest3.out

outfileRED

Now, when an input/output statement in the program refers to logical unit
20, the system uses the equivalence name established for OUTFILE. Thus,

the

following

statement

results

read

from

the

file

DMA1:[SCRATCHITEST3.0UT:
READ

(Z20:9034:B.C

If there is no equivalence name for the logical name OUTFILE when you run
this program, the system assumes that OUTFILE is a file specification. It uses
your current disk and directory defaults and the default file type of DAT to

complete the file specification for the output file.
You can find additional details on how to specify input and output files for

FORTRAN programs in the VAX-11 FORTRAN User’s Guide.

5.4 MACRO Input/Output
VAX-11 Record Management Services (RMS) provide macros for device- and
file-independent input/output operations.
VAX-11 RMS uses control blocks to obtain information about the file or

device you want to access (the File Access Block, or FAB) and the way you
want to access records in the file (the Record Access Block, or RAB).

The $FAB macro constructs a FAB. When you code the $FAB macro, specify
the file name (FNM) parameter to give the file specification of the file or
device to which input/output is directed. For example:

5-6

OUTFAB:

$FAB

FHNM=<WEATHER.S5TS>

OUTRAB:

$RAB

FAB=OUTFAB

Logical Names:

Files for Program Input/Output

The $RAB macro constructs a control block for record processing information.

The $OPEN and $CONNECT macros open the file for processing, and establish the connection between the FAB and the RAB. For example:
$0PEN

FAB=OUTFAR

RAB=0OUTRAB

SCONNECT

When the program uses a $PUT macro to write to the output file defined by
this FAB and RAB, it writes to the file WEATHER.STS. Note that the
system supplies your current default disk and directory name to identify the
file.

You can also specify a logical name with the FNM parameter in the $FAB
macro. For example:
OUTFAB:
OUTRAB:

#FAB
#RAB

FRM=<OUTFILEZ:
FAB=O0OUTFAB

Before you execute the program to write this output file, you can assign an
equivalence name to the logical name OUTFILE, as follows:
$

assidgn

dmal:[Cscratchltest3.out

outfile@ED

Now, when a $PUT macro refers to the RAB established for OUTFILE, the
system uses the equivalence name. For example, the following line in a program results in a write to the file DMAIL:[SCRATCHITEST3.0UT:
SPUT

RAB=O0UTRAB

If thereis no equivalence name for the logical name OUTFILE when you run
this program, the system assumes that OUTFILEis a file specification. It uses

your current disk and directory defaults to complete the file specification,
but does not supply a default file type. The output file would be named
OUTFILE.

5.5 For More Information

For more information about logical names see the VAX/VMS Command Language User’s Guide and the VAX/VMS System Services Reference Manual.
For details about using VAX-11 RMS macros, see the VAX-11 Record Man-

agement Services Reference Manual. Additional information on using logical
names in MACRO programs is contained in the VAX-11 MACRO User’s
Guide.

Logical Names:

Files for Program Input/Output

5-7

Chapter 6

Tailoring the Command Language
As you continue to use the command language, you will discover that it is a
powerful and flexible programming and applications development tool. You
can simplify the command language to save yourself time during interactive
terminal sessions and to establish your own default commands and command
qualifiers. You can create command procedure files to execute batch jobs,
either interactively or from a card reader. You can construct command procedures to perform development and applications programming tasks.
This chapter provides some elementary information on techniques you can

use to tailor the command language to your individual needs. For example,

you can:

e Establish synonyms to use in place of command names and entire command
strings, as well as to establish default qualifiers for commands.
e Create command procedures to perform a specialized set of commands.
e Submit command procedures for processing as batch jobs.

e Use command procedures to perform programming functions, using the
command language as a high-level programming language.

6.1 Symbols
You can equate symbols to character strings or arithmetic values by defining
them in assignment statements. In addition to their use in command procedures (see Section 6.2), symbols are useful as synonyms for long, frequently
used command strings. For example, you can equate the symbol ST to the
command SHOW TIME:
$

"show

time" EED

and subsequently use the symbol ST in place of SHOW TIME:
%

5t @ED

6-1

Symbols can be defined for command lines containing qualifiers as well as
the command itself. For example, if you want to define a synonym for the

DIRECTORY command that automatically includes the /FULL qualifier,
you can define the symbol LIST as follows:
%

list

"directorv/full"@D

Then, if you issue the following command line, the system substitutes the
name DIRECTORY/FULL for the symbol LIST:
%t

list

The

myfile.dat@®D

system

executes

the

command

string

DIRECTORY/FULL

MYFILE.DAT.

Symbols can be concatenated with other symbols or items on a command line.
In this case, the symbol must be enclosed in apostrophes ( ) to indicate to the
system that it must perform symbol substitution. For example, you can assign

the symbol PQUALS to the following qualifiers for the PRINT command:
¢

pauals

"/cories=Z/forms=4/noburst"
@D

Then, to use the symbol with the PRINT command, you must enclose it in
apostrophes:
%

report.dat’pauals’@E

The system recognizes the apostrophes and substitutes the appropriate value
(in

this

case

string

of qualifiers)

for

the

symbol

PQUALS:

REPORT.DAT/COPIES=2/FORMS=4/NOBURST
(Information about the effect of these qualifiers on the PRINT command can

be found in the VAX/VMS Command Language User’s Guide.)

6.2 Command Procedures
A command procedure is a file containing a sequence of commands to be
executed by the operating system. You submit a command procedure with one
command: the Execute Procedure ( @ ) character for interactive processing or
the SUBMIT command for batch processing.

For instance, you could create a command procedure to compile, link, and run
the program AVERAGE mentioned in Chapter 4. First, create a file containing the commands below. (The default file type for a command procedure file

6-2

FORTRAN

LINK

is COM.)

RFUN

AVERAGE

ASEIGN/USER_MODE
AVERAGE

Tailoring the Command Language

TTEZ:

SYSSINFUT

The dollar signs before the commands of a command procedure are required
syntax, indicating that the subsequent line is a command to be executed by
the operating system. (They should be placed in column one of each command
line.)

To execute this command procedure, use the Execute Procedure command
(@ ) as shown below:
¢

Baverade@ED

When this command is executed, the system searches for the file AVERAGE.COM. When it locates the file, the system reads and executes, in turn,
each command line in the file.

Note that to execute this command procedure for the AVERAGE.FOR program created in Chapter 4, you must substitute the device name of your own
terminal for TTB3: in the ASSIGN command (line 3) of the procedure.
6.2.1

Using Symbols in Command Procedures

The sample command procedure shown in the preceding section is not very

flexible: it can be used to compile, link, and execute only the FORTRAN
program named AVERAGE. Command procedures can be made more general
by using undefined symbols in the procedure and defining the symbols when
the procedure is executed.

The following examples show two ways to write a generalized procedure to
compile, link, and run any FORTRAN program.

e Using global symbols in command procedures

If you use the symbol PROGRAM rather than the file name AVERAGE in
the command procedure DOFOR.COM below, you can later assign different
file names to the symbol PROGRAM, making the command procedure in-

HE R

FORTRAN

dependent of a particular source program file.

RUN

LINK

‘PROGRAM

PROGRAM

Before you execute this command procedure you must define the symbol

PROGRAM. Use the assignment statement as shown below:
$

prodram

"averade"
@D

In this assignment statement, the two equal signs are required to make the
symbol PROGRAM a global symbol. Global symbols are recognized and
substituted in any command procedure you execute. (Local symbols, on
the other hand, are restricted by the command level at which they were
assigned; thus, a local symbol assigned in one command procedure cannot
be used outside that command procedure. Local symbols are assigned with
one equal sign.)

Tailoring the Command Language

6-3

Now when you enter the following command line, the system substitutes the
value AVERAGE for the symbol PROGRAM in each line of the command

procedure:
&

Bdofor@ED

If you subsequently redefine the value of PROGRAM to a different file
name and execute DOFOR.COM again, a different source program will be
compiled, linked, and run.
e Passing parameters to command procedures
An alternate way to code the procedure DOFOR.COM is to take advantage

of special symbols that the system defines automatically when you execute
a command procedure. These symbols, called parameters, are named P1,
P2, P3, and so on up to P8, and are defined on the @ command line.

For example, assume that DOFOR.COM has the lines:
F

ORTRAN

LINKE

FURM

P17

“P1°

“F1°

To define a value —in this example, the file name
— for the symbol P1,
enter the file name when you give the @ command to execute the command

procedure DOFOR.COM, as follows:
%

Bdofor

averasge@e

The system automatically equates the name AVERAGE to the symbol P1,
the first (and, in this example, the only) parameter passed to the command
procedure. P2 through P8 are equated to null strings. When the command
procedure executes, the value AVERAGE is substituted for the symbol P1.

6.2.2

Redefining System Commands

You can use command procedures and symbol assignment statements together to redefine and expand system commands.
For example, suppose that during your terminal sessions you frequently compile and recompile programs, creating many listing files (with a file type of

LIS). To keep your directory uncluttered, you may want to purge these listings regularly. To do this housekeeping, you could create a command procedure named LOG.COM that contains the lines:
$

PURGE

LOGOUT

#.LIS

You can use this command procedure in place of the LOGOUT command
when you want to end your terminal session, as follows:
%

6-4

[B1odRED

Tailoring
the Command Language

The PURGE command line is automatically executed before you log out.

Moreover, you could define a symbol named LO that is equated to the following command string:
g

"Blog"
@

Then, when you type the command line
¢

1 0(@ED)

the system substitutes the symbol LO with the @ LOG command string, and
executes your command procedure.

6.2.3

A LOGIN.COM File

If you become a frequent user of the VAX/VMS system, you may find that you
are entering the same sequence of commands or assignment statements every

time you log in. To avoid such repetition, you can place these commands and
statements in a special command procedure.

The command procedure file must be named LOGIN.COM, and it must be in
your default disk directory. When you log in to the system, the system automatically searches for a file with this file name. If the system locates the
LOGIN.COM file, the system automatically executes the commands within
that file.

For example, a LOGIN.COM file might contain:
&

LIST

"SHOW

ASSIGH

TEST

TIME"

"DIRECTORY"

"ELOGY

[MALCOLM.TESTFILEE]

"SET

DEFAULT

TEST

[MALCOLM.TESTFILESI®

Note that all the symbols defined above are global symbols, assigned with two
equal signs. If these symbols were local (assigned with one equal sign) they
would be recognized only within the LOGIN.COM file, and would therefore be
useless to you.

Command procedures can be executed from within other command procedures. You may want to place the global assignment statements you use for

command synonyms in a separate file, and execute this procedure in the
LOGIN.COM file. For example, suppose the file SYNONYM.COM contains
the lines:

LIST

"DIRECTORY®

®*RLOGY

Your LOGIN.COM file would contain the line:
£

EEYNMONYH

the Command Language
Tailoring

6-5

When this command is executed, the definitions in the synonym file are
established.

6.3 Batch Job Processing
If you use the Execute Procedure command ( @ ) interactively, you cannot
enter other commands to do other work while the procedure is executing. If

you want to execute a command procedure that requires a great deal of processing time, you can submit the command procedure as a batch job. When
you submit it, the batch job is queued by the operating system; your terminal
is then free for you to continue working interactively.
Use the SUBMIT command to request the operating system to place the
command procedure in the batch job queue. The SUBMIT command assumes
your current disk and directory defaults, as well as the default file type of
COM. For example:
$

DOFORGED

SUBMIT

Job

312

entered

aueus

SYS5FBATCH

In this command, DOFOR is the file name of a command procedure. The

system responds to the SUBMIT command with a message indicating that
the job was successfully queued to the SYS$BATCH queue and has the job
identification number of 312. As soon as the batch job is queued, you can
continue interactive use of the terminal; the system will process the batch job.

6.4 Programming Command Procedures
The examples of assignment statements and command procedures in this
chapter show only a few things you can do with command procedures. There is
a special set of commands that you can use in command procedures to perform functions similar to those available in high-level programming lan-

guages. Some brief examples of these commands are shown below to illustrate
the versatility of VAX/VMS command procedures. You can:
® Assign arithmetic values to symbol names, and use these symbols in assignment statements with arithmetic expressions. For example:
&

COUNT

% CGUHT == COUNT + 1
e Transfer control to a command line in a procedure that is not the next line

6-6

LOOP:

in the file. For example:

COTO

LOOP

Tailoring the Command Language

e Conditionally execute a command based on a comparison of values, strings,
or symbols. For example:

& IF COUNT.LT.10 THEN GOTO LOOP

e Interactively define a value for a symbol by displaying a prompting message
on the terminal. For example:
$

INOUIRE

NUMBER

TF NUMBER.EG.1

THEM GOTO NEXT

e Establish a default course of action should an error occur during prvocessing |
of any command or program. For example:
$

ERROR

THEMN

EXIT

'6.‘5 For More Information

For additional examples of developing command procedures, see the
VAX/VMS Guide to Using Command Procedures.

Tailoring the Command Language

6-7

Glossary

assembler

Language processor that translates a source program containing assembly language
|

directives and machine instructions into an object module.

assembly language

Machine oriented programming language. VAX-11 MACRO is the assembly lan-

guage for the VAX-11 computer.

assignment statement

Definition of a symbol name to use in place of a character string or numeric value.
Symbols can define synonyms for system commands or can be used for variables in
command procedures.

batch

Mode of processing in which all commands to be executed by the :operating system

and, optionally, data to be used as input to the commands are placed in a file or

punched onto cards and submitted to the system for execution.
buffer

A temporary storage area.

command

An instruction or request for the system to perform a particular action. An entire
command can consist of the command name, parameters, and qualifiers.

Glossary-1

command interpreter

The operating system component responsible for reading and translating interactive

and batch commands. The default command interpreter for the VAX/VMS operating
~ system interprets the DIGITAL Command Language (DCL).

command line

The entire command string, including
the command and any parameters or qualifiers
it may have.

command procedure

File containing a predefined sequence of commands to be executed by the operating
system. The command procedure can be submitted for execution at the terminal or as
a batch job..

compiler

Language processor that translates a source program containing high-level language
statements (for example, FORTRAN) into an object module.

concatenate

To link together in a series.
'

cursor

A line or block indicator used in a video display terminal to indicate position.

debugger

Interactive program that allows you to display and modify program variables during
execution and to step through a program to locate and detect programming errors.

default

Value supplied by the system when a user does not specify a required command
parameter or qualifier.

default disk

The disk from which the system reads and to which the system Wr'ites, by default, all
files that you create. The default is used whenever a file specification in a command

does not explicitly name a device.

delimiter

~ Character that marks the beginning or end of a string.

2-Glossary

device name

Identification of a physical device (for example, DBA2) or a logical name (for exam-

ple, SYS$OUTPUT) that is equated to a physical device name.
directory

File cataloging a user’s files on a particular device for a user.
editor

Program that creates or modifies files. In VAX/VMS, the default system editor 1s
|
|
interactive.

equivalence name

Character string equated to a logical name, such that when a command or program
refers to a file or device by its logical name, the system translates the logical name to
its predefined equivalence name.

file

Collection of data treated as a unit; generally used to refer to data stored on magnetic
|
|
tapes or disks.

file name

The name component of a file specification, consisting of from one to nine characters.
file specification

Unique identification of a file. A file specification describes the physical location of
the file, as well as file name and file type identifiers that describe the file and its
contents.

file type

" The type component of a file specification, consisting of from one to nine characters.
A file type generally describes the nature of a file, or how it is used. For example,
FOR indicates a FORTRAN source program.

global symbol

A symbol defined with an assignment statement that is recognized in any command
procedure that is executed.

| header page

Printed page at the beginning of a listing that identifies the printed file.

Glossary-3

image

Output from the linker, created from processing one or more object modules. An
image is the executable version of a program.

input file

File containing data to be transferred into the computer.
interactive

Mode of communication with the oper'ating system in which a user enters a command, and the system executes it and responds.

‘

job

(1) The accounting unit equivalent to a process; jobs are classified as batch or interactive. (2) A print job.

keypad

The small set of keys next to the main keyboard on a terminal. -

keyword

A command name, qualifier, or option. Keywords must be typed verbatim or truncated according to the rules of DCL.

line editor

Program that allows you to make additions and deletions to a file on a line by line

basis.

linker

Program that creates an executable program, called an image, from one or more
object modules produced by a language compiler or assembler. Programs must be
linked before they can be executed.

local symbol

A symbol defined with an assignment statement that is recognized only within the
command procedure in which it is defined.

logical name
Character string used to refer to files or devices by other than their specific names. A
command or program can refer to a file by a logical name; the logical name can be

equated to an equivalence name
at any time; when the command or program refers to
the logical name, the system translates the logical name to its defined equivalence

name.

4-Glossary

’

To perform a sequence of actions at a terminal that establishes a user’s communica-

tion with the operating system and sets up default characteristics for the user’s
terminal session.

log out

To terminate interactive communication with the operating system. The LOGOUT
command executes the procedure and ends a terminal session.

machine code

A sequence of binary machine instructions in a form executable by the computer.

network

A collection of interconnected corhputer systems.
node specification

The component of a file specification which identifies the location of a computer
system in a network of computer systems.

object module

Qutput from a language compiler or assembler that can be linked with other object
modules to produce an executable image.

operating system

The system software that controls the operations of the computer.
output file

File to which the computer transfers data.
parameter

Object of a command. A parameter can be a file specification, a symbol value passed
to a command procedure, or a word defined by the DIGITAL Command Language.

password

Protective word associated with a user name. A user logging in to the system must
supply the correct password before the system will permit access.

v‘prompt

Word(s) used by the system as cues to assist a user’s response.

(Glossary-5

qualifier

Command modifier that describes the operation of a command. A qualifieris always

preceded by a slash character (/).

queue

A line of items waiting to be processed.

range specification

Used with EDT line editor to define the line(s) to be affected by the editing com-

mand.

reverse video

A feature of the VT100 terminal that reverses the default video contrast. If black
figures upon a white background is the default, reverse video displays white upon
black. Used with some EDT keypad commands to highlight a range of text.
scrolling

A feature of a video terminal that allows the display of more than one screenful of

text by vertical movement.

source program

A program written in a language other than machine code that must be compiled or
assembled to be used.

subdirectory

Directory file cataloged in a higher-level directory that lists additional files belonging
to the owner of the directory.

terminal

Hardware communication device, with a typewriter-like keyboard that receives and

transmits information between users and the system.

user name

Name by which the system identifies a particular user. To gain access to the system,
a user specifies a user name followed by a password.

version number

Numeric component of a file specification. When a file is edited, its version number is

increased by one.

6-Glossary.

wild card character

A symbol used with many DCL commands in place of all or part of a file specification

/—n—z- .

to refer to several files rather than specifying them individually.

Glossary-7

Index

A
Assembler, 4-2

Cursor, 1-6, 2-6, 2-8

Assembly language, 4-2
Assignment statement, 6-1 to 6-2

DCL, 1-5

Default, 1-7

file specification, 3-1
logical names, 5-3
Device name, 3-2

Batch

DIGITAL Command Language 1-5

editor, 2-2

Directory, 3-2 to 3-3
change of default, 3-8

job, 1-1, 6-6
user, 1-1

Documentation, VAX-11, viii

C
Command, 1-4
. abbreviation, 1-6
EDT subset of, 2-14, 2- 19
format, 1-4

HELP, 1-8 to 1-9
1-4
language,

parameter, 1-4
prompt, 1-5

qualifier, 1-4
Command procedure, 6-2
LOGIN.COM file, 6-5
parameters in, 6-4
symbols in, 6-3

Compile commands, 4-2
-

Compiler, 4-2

Control key, 1-6 to 1-7

E
Editor, 2-1, 2-2
batch, 2-2
default, 2-3
EDT

See EDT
interactive, 2-2

SOS, 2-2
SUM, 2-2

SUMSLP, 2-2

EDT, 2-1
HELP, 2-4, 2-15
invoking, 2-4, 2-15

keypad command subset, 2-14

keypad editor, 2-3 to 2-13

line command subset, 2-19
line editor, 2-14 to 2-19

Index-1

EDT (Cont.)
range specification, 2-16
termination of, 2-5, 2-16

Keypad, 2-3

Equivalence name, 5-1

diagram of, 2-3

Error message, 1-8

editor, 2-3 to 2-13
Keypad commands

subset of, 2-14
Keypad editor

File, 2-1

cursor manipulation, 2-6, 2-8

COPY command, 3-9

creation of, 3-5

Keys

control, 1-6 to 1-7

default specification, 2-1

Keyword, 1-4

deletion of, 3-5, 3-6
display of, 3-6

identification of, 3-1

list of in directory, 3-7 to 3-8

Language

name, 2-1, 3-3

assembly, 4-2

PRINT command, 3-7

high level, 4-2

PURGE command, 3-6

Line commands

RENAME command, 3-10

subset of, 2-19

specification

Line editor, 2-14 to 2-19

See File specification
type, 2-1

~ Linker, 4-3

3-3, 3-4

Local symbol, 6-3

version, 2-1, 3—4
File name, 2-1, 3-3

Logical name, 5-1

ASSIGN command, 5-1

File specification, 3-1

equivalence name, 5-1

device name, 2-1

in commands, 5-2

directory, 2-1

system default, 5-3

file name, 2-1

file type, 2-1

node name, 2-1

Logout, 1-9

version number, 2-2

File type, 2-1

3-3, 3-4

default, 3-4, 4-1

File version, 2-1, 3-4

Message
error, 1-8

| Glebal symbol, 6-3
Network, 2-1

Node, 2-1

Node name, 2-1, 3-1

HELP command, 1-8 to 1-9

DCL, 1-8 to 1-9
EDT, 2-4, 2-15

Object module, 4-3
Operating system, 1-1

P
Image, 4-3

Parameter, 1-4

Interactive
editor, 2-2
user, 1-1

Index-2

Password, 1-2 to 1-3
~

Program, 4-1

assembly of, 4-2

Symbol (Cont.)

Program (Cont.)

global, 6-3

compiling, 4-2

creation of, 4-1
execution of, 4-3
Program development
FORTRAN example, 4-5 to 4-9
MACRO example, 4-10 to 4-14

local, 6-3

Terminal
hardcopy, 1-1

keyboard, 1-3
video, 1-2

Qualifier, 1-4

- User name, 1-2

Range specification, 2-16

S
Subdirectory, 3-3
creation of, 3-8

Symbol, 6-1, 6-3
assignment statement, 6-1

\Y
VAX-11 documentation, viii
Version number, 2-2

Wild card character, 3-4 to 3-5

Index-3

VAX/VMS Primer
AA-DO30C-TE

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