The TELNET port driver (TNDRIVER) provides terminal session
    support for TCP streaming connections using the RAW, NVT, RLOGIN,
    and TELNET protocols. Either a remote device or an application
    can be present at the remote endpoint of the connection.
    A user program can manage a TELNET connection with the standard
    OpenVMS $QIO system service by using the IO$_TTY_PORT and IO$_
    TTY_PORT_BUFIO I/O function codes.