VMS Help TCPIP Services, TELNET, Starting  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    You can start a TELNET or TN3270 session with a remote host (also
    called establishing a connection and opening a connection) in one
    of the following ways:

    o  At the DCL prompt, issue either the TELNET or TN3270 command
       and specify a remote host.

    o  At the DCL prompt, issue the TELNET or TN3270 command with no
       parameters. At the TELNET or TN3270 prompt that appears, issue
       the CONNECT or open command, specifying a remote host.

    o  Invoke and use TELNET or TN3270 from a command procedure.

1 - Example

    The following example shows three ways to establish a connection
    interactively:

    $ TELNET CENTRAL /TERMINAL_TYPE=IBM-3278-2

    $ TELNET
    TELNET> CONNECT CENTRAL 23 VT200

    $ TN3270 CENTRAL /TERMINAL_TYPE=IBM-3278-3

    You can invoke TELNET or TN3270 and, without connecting to a
    remote host first, enter certain commands that customize the
    sessions and display parameters or status.

    $ TELNET
    TELNET> SHOW STATUS
    %TELNET-E-NOSESSION, No active session
    Escape character: '^]'
    TELNET>SET DEVICE TERMINAL=VT300
    TELNET> OPEN GALAXY
    %TELNET-I-TRYING, Trying ... 1.20.208.10
    %TELNET-I-SESSION, Session 01, host galaxy, port 23
    -TELNET-I-ESCAPE, Escape character is ^]

    Digital UNIX (galaxy.udb.com) (ttyp5)

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