inheriting processes from other ttys

[Ron Natalie]

Actually, I have a program that sort of emulates the DEC-20
attach/detach feature.  I prototyped it in user mode with the
hope that someday I would get around to putting it in the kernel.
What it does is snatch a pty for your session and map that to
a regular hard tty line.  If you explicitly detach, hang up the
phone, or are inactive for a specified period of time, the
pty releases the hard tty line and goes into a dormant state.
A simple command from another hard terminal remaps it to the
new terminal.

-Ron