Using either one of the VT100 Terminals in Cooke 103 or one of the computers in Cooke 110:
Hit return several times until the USERNAME> prompt appears. Type in your name/initials and hit RETURN.
When the LOCAL> prompt appears type C (for connect).
When the VAX USERNAME: prompt appears type your login name (Usernames are you initials followed by the course ID ABC_235001) followed by your password. Passwords are initially the same as your login name and must immediately be changed. You should choose a non obvious mix of letters and numbers at least six characters long. NOTE: For security, anything dealing with your password is NOT displayed on the screen!!!
When you have finished your VAX/VMS session: type LOGOUT (or LO for short) and press
Each time you modify a file and save the changes, VMS adds a new version of the file to your directory. For example,
are two versions of the same file. The number of each new version is one higher than the existing version number. That is, a file that is version 4 was created after version 3 (but not necessarily from 3--it could have been created from 1 or 2). The VMS system saves previous versions of a file as backups.
Most VMS commands use the most recent version of a file unless you specify otherwise.
VMS commands that create files assign default file types. Common file types in VMS include:
DELETE gets rid of individual files. For example, if you have two files, sample.dat and newsample.dat and you want to discard sample.dat, you would use the DELETE command:
All Instructional (class) accounts will have a version limit of 2 placed on their files. This means only 2 versions of the same file will be saved in your area. If you wish to save a previous version, before editing version #3, it will be necessary for you to "rename" the first version of that file. See section entitled "VMS commands" or type HELP RENAME at the dollar sign prompt for more information on how to rename files.
PURGE will discard groups of files. For example, if you want to discard all but the last version of a file, you use the command:
There are several important keys used in conjunction with the CONTROL KEY on the VAX. By holding down the control key WHILE you type a second key, that second key will perform a special function. The most important of these special keys are:
CTRL/Y Cancels all activity from last command at your terminal
(Acts as a panic button)
If you are in the editor, it kicks you out and creates
a journal (.JOU)
CTRL/C If you are in the editor, cancels the last editor command.
If you are giving a command at the dollar sign prompt, acts
the same as CTRL/Y.
CTRL/U Erases one command line (if you press CTRL/U before you press
the return key.
CTRL/R Retypes previous command line (this is used when you are on
a terminal or pc and the backspace or delete key does not
actually eliminate the character from the screen, but does
eliminate it in the buffer - before press the return key,
press CTRL/R and the buffer contents will be displayed)
If you are in the editor, it refreshes the screen.
CTRL/W If you are in the editor, it refreshes the screen.
CTRL/S Suspends terminal output. For instance, you can "freeze"
the lines of your output on the screen by typing CTRL/S.
CTRL/Q Resumes terminal output (which has been
suspended by CTRL/S)
NOTE: In the following examples, "filename" refers to the entire filename including the extension, e.g. PROGRAM1.COB
Some of the most frequently used DCL commands are:
The system will respond with a logout message and you will be logged out.
Type LOGOUT (or LO) again to log off the file server.
FILE MANAGEMENT
File Specifications
The VAX has a unique file specification to identify each file. The file specification includes the name, type, and version # of the file.
MYFILE.DAT;1
______ ___ ___
| | |
| | The version number distinguishes it from other
| | copies of the file. The version number is
| | connected to the file type by a semicolon(;)
The filename specifies |
the name of the individual |
file within the directory. |
The filename can contain |
from 1 to 39 letters and |
numbers. |
The file type specifies the contents of a file. It
can be from zero to thirty-nine characters and must be
preceded by a period. Again, you can choose from the
letters A through Z and the numbers 0 through 9.
sample.dat;1
and
sample.dat;2
.COM A command procedure file ( see BATCH MODE)
.DAT default extension for a data file
.JOU default extension for a file created when
edit mode is aborted
.LIS default extension for an output listing file
.COB default extension for a COBOL source file
.OBJ object file
.EXE executable file
Wild Cards
If you replace part of a file specification with an asterisk (*), the command you give refers to all files that match the other parts of the specification. For example, PRINT *.INP prints all files that have the file type INP. PRINT *VERY.* will print every file with a filename ending in VERY (note this differs from MSDOS)
Deleting Files
Since VMS creates new versions of files automatically, your account can become crowded with unnecessary and obsolete files very quickly. It is recommended that you delete any files that you do not need before you logout. The two commands that will get rid of files for you are DELETE and PURGE.
$ DELETE sample.dat;1
DELETE requires a specific version number or a wildcard:
$ DELETE sample.dat;
will delete all versions of sample.dat
$ PURGE sample.dat
If you do not specify a file for the purge command, it purges everything in your directory.
Control Keys
To correct a mistake while typing on the terminal keyboard, use the VMS COMMANDS
Commands under VMS consist of the command name and qualifiers
and parameters. For example, in this command
PRINT/COPIES=2 SAMPLE.DAT
PRINT is the name of the command. It tells the system to
print a file.
COPIES=2 is a qualifier that describes how you want the command
to work. In this case you want to print 2 copies of
the output. All qualifiers are preceded by a slash (/).
SAMPLE.DAT is a parameter that describes what you want the command
to work on. In this example, you want to print the file
SAMPLE.DAT. All parameters are preceded by a space.
If you do not specify a qualifier with a command, the system will assume DEFAULT qualifiers. If you do not specify a parameter with your command, the system will prompt you for the parameter.
APPEND Adds the contents of one or more specified input files to the
end of a specified output file.
EX: APPEND filename#1 filename#2
ASSIGN Equates a logical name to a physical device name or file.
EX: ASSIGN FILENAME FOR005
COPY Creates a new file from one or more existing files.
Copy can duplicate one file to another file, or duplicate
a group of files to another group of files.
EX: COPy data1.dat newdata.dat
CREATE Creates a file but doesn't give you edit capability.
Very useful for uploading files from PCs.
EX: CReate PROG1.FOR
CREATE/DIRECTORY creates a subdirectory in your default directory
EX: CReate/DIR filename
DEASSIGN Cancels logical name assignments made with the ASSIGN command
EX: DEASSIGN FOR005
DELETE Deletes one or more files from disk, i.e., makes a file not
accessible to the user, takes it out of his/her directory.
(Note that the version # must be included in the filename
or the wildcard character "*" if all versions of the file
are to be deleted.)
EX: DELete file1.dat;1 (deletes version 1 only)
DELete file1.dat;* (deletes ALL files named "file1.dat")
DIFFERENCES
Compares the contents of 2 disk files and creates a listing of
those records that do not match.
EX: DIFF filename#1 filename#2
DIRECTORY
Lists all files the user has in his/her default directory
and optionally, all files in sub directories.
EX: DIR
EDIT Enters edit mode to create or modify a file.
EX: EDIT SAMPLE.INP
HELP Lists information on topics on terminal screen
(to get out of help do press the return key until the $ prompt
appears or press CTRL/Y)
LOGOUT command to sign off the VAX system. This does not get you out of
the network. The terminal does not time out, so if you do not logout
and just turn the terminal off, the next person who turns the terminal
on will be in your account.
MAIL Method to communicate with other users.
PRINT Sends a file to the print queue to be printed.
PURGE Deletes all but the highest-numbered version of the file
If you specify a filename, purge works on the versions of that
file. If you do not specify a filename, PURGE works on the
entire directory.
EX: PURge DATA.DAT (will delete all but highest version)
PURge (deletes all but highest version of all
files in your directory)
RENAME Changes the name of filename #1 to filename #2
EX: REN filename#1 filename#2
REQUEST "message goes between quotes" Sends a message to the operator
SHOW TIME
tells current day and time
SHOW DEFAULT
shows the current directory
SHOW LOGICAL
shows current logical assignments
SUBMIT Command to start a batch job
TYPE Lists contents of file on terminal screen.
EX: TYpe PROGRAM1.FOR