job control

Hello all,
I have a seemingly simple question, but I fear it entails some underlying
complexity. I need a program (using perl and curses) to run under at and
take absolute priority on a users terminal at a specified time (the user
will be logged in with ssh and may be logged into another computer via
minicom or kermit). Now I know job control (nice, renice, bg, fg, etc) but
this app must take absolute priority over what they are doing and be
interactive on their terminal. Am I safe messing around with priorities and/
or suspending the user's jobs during the duration of my program or is there
a better approach to this? Thanks for taking the time to read my post.

Joel Dudley
Unix System Administrator
DevelopOnline.com
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