help sought - securing a terminal/line

[Guy Harris]

>Under Unix-like OS's, you can run any program you like in place of the login
>by modifying the /etc/inittab file.  Under Xenix there is a somewhat obscure
>thing you can do in /etc/gettydefs to cause a program besides getty to run.
>
>Someone else posted something about /etc/ttys.  I think the above info is
>correct.

The above info is correct for UNIX-like systems that have "/etc/inittab"
files (assuming "the login" actually refers to "getty", which is
normally what is run out of "/etc/inittab" for most ports).

For UNIX-like systems with 4.3BSD-style "/etc/ttys" files (even if
called "/etc/ttytab", as was done in SunOS for binary-compatibility
reasons), the info posted about "/etc/ttys" is correct. 

For UNIX-like systems with "ttymon", such as System V Release 4, I think
there's some other magic you can do to arrange that "ttymon" run your
program when the port starts up.