/sys$common/syshlp/helplib.hlb PHONE, Parameter  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 phone command

    Specifies an optional Phone utility command that enables you to
    control your phone conversation. You can specify a PHONE command
    parameter as part of the PHONE command line, or you can enter one
    at any time during the phone conversation by typing the switch
    hook character (%) and the desired command. The following list
    summarizes the functions of each Phone utility command:

    ANSWER      Answers the phone when you receive a call.
    DIAL        Places a call to another user.
    DIRECTORY   Displays a list of the users you can call.
    EXIT        Exits from the Phone utility.
    FACSIMILE   Includes the contents of a file in your conversation.
    HANGUP      Cancels the current phone call.
    HELP        Displays information on how to use the Phone utility.
    HOLD        Places the other users in a call on hold.
    MAIL        Sends a message to another user.
    PHONE       Places a call to another user.
    REJECT      Rejects a call from another user.
    UNHOLD      Reverses the previous HOLD command.

    For a detailed description of each Phone utility command, invoke
    the Phone utilty and type HELP at the switch-hook prompt.