/EDIT[=(keyword[=option], . . . )]
    Sets the default to /EDIT for the SEND and REPLY commands and
    allows you to edit your mail messages. By default, the DECTPU-
    based EVE editor will be invoked. You can use the SET EDITOR
    command in MAIL to change your editor.
    Valid keywords are FORWARD, REPLY[=EXTRACT], and SEND.