Introduction to the OpenVMS Operating Environment

Access to OpenVMS

Requirements for Accessing an OpenVMS System

To access an OpenVMS system, you must have an OpenVMS user name and a password. In SAS documentation, the user name is usually called the user ID. Ask your supervisor or system manager for a user ID, a password, and any other information that you might need to access OpenVMS at your site. For example, if your system is part of a DECnet for OpenVMS network, then you also need to know how to access the appropriate computer system before you begin the login procedure.

The login procedure differs from site to site, depending on how your system is configured.

When OpenVMS prompts you for your user ID, type the user ID, and then press the ENTER key. Next, the system prompts you for your password. Type the password, and then press ENTER. OpenVMS accepts and validates the user ID and password, even though you cannot see the password on the monitor. Next, you might see messages welcoming you to the OpenVMS system. If you enter an incorrect user ID or password, you must start the login procedure again.

The following sequence illustrates the login procedure:

Username: user-ID   <ENTER>
Password:          <ENTER>
. . . system messages . . .

$

When you log in, OpenVMS defines the environment in which it responds to your DCL commands. This environment is called your OpenVMS process.

Certain default characteristics are associated with your process, such as a default disk, a directory name, and resource quotas. This information is taken from the user authorization file. A command interpreter (usually the DCL interpreter) is also associated with your process.

After you have logged in successfully, the system typically displays a dollar sign ($) to indicate that it is ready to accept a command. However, a different symbol might be used at your site, or you might use a menu interface. In this document, all examples assume that your OpenVMS system uses the $ symbol as the system prompt and that it uses the DCL command line interpreter.

Files That Affect the Login Procedure

User Authorization File

During the login procedure, OpenVMS accesses a file called the user authorization file (UAF) to validate your user ID and password. The UAF is maintained by your system manager, and it contains a record for every person who is authorized to use the system.

Besides the user ID and password, the UAF record for each user specifies the user's default disk and default directory. Thus, each time you log in, your session is attached to the default disk at a location called your default (or home) directory. The UAF also specifies the access privileges and quota limits that are associated with your user ID.

LOGIN.COM File

At some sites, the system manager creates a login file, LOGIN.COM, in your home directory when you are authorized to use the system. This file contains DCL commands and utilities that are commonly used at your site.

When you log in, the OpenVMS system automatically searches for the LOGIN.COM file in your home directory. If one exists, the system executes the commands in the file before you receive the first DCL prompt (often the $ symbol).

If you find that you regularly use certain DCL commands and utilities to customize your process, you can avoid entering these commands every time you log in by storing them in the LOGIN.COM file in your home directory.

Check with your system manager first before deleting or moving your LOGIN.COM file. You can create or modify the LOGIN.COM file using an OpenVMS editor.

For example, suppose that user John Smith has the following LOGIN.COM file stored in his home directory [SMITH]:

$ !  Login command file for John Smith
$ SHOW TIME

Each time Mr. Smith logs in, the command file executes automatically, and displays the current date and time. Note that the $ prompt is generally in column 1 of each line that contains a DCL command. (A file containing just "SHOW TIME" will also work.) To improve readability, you can insert one or more blanks after the $.

Note: If you use assignment statements in your LOGIN.COM file to create symbols, make sure that they are global assignments by using a double equal sign (==); otherwise, the symbols will be local to the LOGIN.COM file. In other words, an assignment statement that uses a single equal sign (=) creates a symbol that exists only while the LOGIN.COM file is executing. [cautionend]

The following is an example of a global symbol assignment statement. Mr. Smith modifies the LOGIN.COM file by deleting the SHOW TIME command line and adding the following assignment statement:

$ DT == "SHOW TIME"

With this modification, Mr. Smith can request the current date and time during his terminal session by entering the following line:

$ DT

For more information about global and local assignments and about the LOGIN.COM file in general, see OpenVMS User's Manual.

Logout Procedure

When you are finished using the system, enter LOGOUT at the DCL prompt. The system displays a message to confirm that you have logged out.

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