permissions and parameters on terminal line

[NRAO Array Operations Center]

I have a user with a device attached to a serial line which he is writing a
program to talk to. The problem is this: I don't particularly want to install
his program setuid root, so how do I get the system to set the ownership of
the terminal device at boot time so that it will stay that way as long as the
system is up? Currently, every time he runs the program he has to first run
something I gave him the change the ownership, and then after his program
finishes the device reverts to root.

Running a daemon on the line is not a nice solution, either, since if it dies
for some reason the same problem crops up. Ideally I would like to be able
to say something in /etc/rc.local like:

chown -permanent him /dev/tty1c
stty -permanent 4800 raw /dev/tty1c

Obviously these commands won't work, but is there something else in stock
UNIX which will? init won't work because every time it wakes up it interferes
with his program; I have had to turn it off on that line.

The system is a Solbourne 5/801 (SPARC CPU chip) running OS/MP 4.0c (= SunOS
4.0.3).

Thanks in advance. Please reply by email and I will post the final solution.
-- 
Ruth Milner
Systems Manager                     NRAO/VLA                    Socorro NM
                            rmilner at zia.aoc.nrao.edu