The information in this document is obsolete. All CLASSE VMS computers were shut down on January 17, 2017.

All commands can be either lowercase, uppercase, or mixed case. VMS is not case-sensitive. OpenVMS has one main "shell" that is called DEC Command Language (DCL). It can be used to craft standalone programs to automate certain tasks and enable data processing.

Command	Description	Example
LO, BYE, LOGOUT	Log off the system
TYPE	Dumps contents of a file to the screen
LS	Compact directory listing (multiple columns)
DIR	Full directory listing with modification dates (single column)
CREATE/X	Create a new {X: FILE, DIRECTORY, etc...}	CREATE/DIRECTORY [.TESTING] Makes a new directory called "testing" in the current working directory.
sea	Search (grep) for string	sea <filename> "string"
display	Shows CPU usage on current node.

Conventions

Convention Syntax	Meaning
=[.<directory>...]	Operate on the subdirectory "directory" that is one level deeper than the current directory " . " and recurse through all subdirectories ... .

Examples

del [subdirectory-name]*.*;*	Deletes all files in a subdirectory of the current directory.
set protection=o:rwed subdirname.dir	Sets permissions to allow delete on a subdirectory of the current directory.

Useful Programs

Name	Description
tpu	Simple text editor
emacs	The venerable emacs text editor, development environment, OS, what have you..

Official reference documents are here:

• DCL Dictionary A-M
• DCL Dictionary N-Z

Someone else has also written a fine beginner's summary. It is here.

Debugger

The VMS debugger can run in two modes, text based with limited console windowing and also in a mode that provides a full GUI. While the GUI may be more powerful, it is certainly slower and each mode has its own advantages.

Generally:

• set break <function name> -- Setss a breakpoint based on function name
• set break %line <line number> -- Sets a breakpoint based on line
• step -- Steps to next executable statement
• go -- Runs continuously from current position (or start) to end of program (or next breakpoint)
• set step over -- Mode change to step over function calls to next executable line in current file
• set step into -- Mode change to step into function calls and change scope.
• The online help can provide many more valid commands.

The official VMS Debugger manual is here (PDF).