host
Required.
Remote host to which you want to connect.
port
Required.
TELNET port on the remote host.
unit
Optional. Default: 0
The decimal number specifying the unit number for the pseudo
device (TNAx). The default 0 specifies that TCP/IP Services
should pick the next available unit number. If the requested
unit number is already in use, the next available unit number is
used. In all cases, the software notifies you of the unit number
chosen.