The MAIL command is used to send a short phone message to another person.
This is useful when you cannot reach someone and would like to let them
know that you called.  The command requires the user name of the person to
receive the message and a message enclosed in quotation marks (").  Thus
the full syntax is:

        MAIL [node::]user-name "short message"

The standard VMS MAIL facility is used to send the phone message.