Can a script check if my line is dialup?

[Guy Harris]

>tset uses the /etc/ttytype file as a database mapping terminal types to
>tty lines.

"tset" on *some* systems *might* use "/etc/ttytype" as a database
mapping terminal types to tty lines; I've never seen any such system,
but perhaps Wyse's flavor of UNIX is one such system?

Some systems - e.g., 4.3BSD, and probably therefore nExt's OS, use
"/etc/ttys" (or "/etc/ttytab", if they had to keep "/etc/ttys" in the
old format for backwards compatibility), as that table, and in the cases
I've seen it's "login", not "tset", that uses it, and sets the TERM
environment varible; "tset" just looks at that environment variable.