Everything you ever wanted to know about VMS and were afraid to ask

Help with all DCL commands can be found by typing HELP Command. This helper gives a quick guide to some of the commands you may need to know about, to find you way round the system. Note VMS is not case sensitive - use upper or lower case as you wish. Commands may be abbreviated to their first few letters (you need enough letter to be unambiguous, usually 3 by sometimes 2).


When you log into the uVAX as user MULTI, your current directory will be $DISK1:[CORR] with subdirectories for different groups to use. Directory names are enclosed in [ ] and subdirectories separated by dots.

Changing directory

Moving to another directory is done with the command
       SET DEFAULT diskname:[directoryname]    
This can be abbreviated to SET DEF [dir] or SD [dir] or (with luck) CD [dir] You can give the full name of the disk and directory.subdirectory eg. SD $DISK1:[CORR.LASER] or you can move relative to your current directory ( . = current, - =up).
current directory       command                result

Typing HELP SET DEF at the prompt will give the full VMS help text for this command.

Where am I?

You can find your current position using the command SHOW DEFAULT, which can be abbreviated to SHO DEF or possibly pwd.


File names can be a combination of almost any letters and numbers (a notable exception is +) and consist of a name, a dot, an extension and version number, e.g.} NAME.EXT;1.
No file is ever lost or overwritten, any edit or copy command produces a file with a new version number. A file must be deleted to get rid of it.

File List

To get a list of the files in the current directory use the command DIRECTORY. This can be abbreviated to DIR or maybe ls. More information can be produced by adding modifiers to the command.

Moving Files

Files can be copied to another directory, or the same directory with another file name with the command COPY. Any part of the dilename (disk, name, extension) that is ommitted will be given th at part of the original name.


The up and down arrows on the keyboard will recall previous commands. These command lines can be edited using the backarrow, and delete keys. The following commands may be useful More information on these and other VMS commands can be found by typing HELPEditing Typing ED filename will bring up the VAX Editor to create or edit a file. In an existing file you can use the arrow keys to move around, then add new data or delete old data. (The editor always works in insert mode ie anything typed will be inserted at the current cursor position, you can't type over existing data.) Commands are summoned using the right hand key pad (and the small block of keys to the left of this). This makes using the editor from a Unix box rather inadvisable!) You can also use emacs, as long as you can remember the key commands! Editing a file creates a version of the file with a higher version number. You will always have the last version to go back to if necessary. ( DIR/DATE/SIZE or DDS will show all the files, with version numbers and creation dates).
Last modified: Thu Jun 15 14:01:06 BST 2000