modifying UNIX environment (was: Iconitis)

[Doug Gwyn]

In article <29192 at apple.Apple.COM> austing at Apple.COM (Glenn L. Austin) writes:
>You can do the same thing in MSDOS as you can in UNIX -- find the original
>copy of the environment table and modify it.  It isn't too hard to do for
>UNIX programs, especially shell scripts.

In fact it's impossible for an unprivileged user process running on
a properly configured UNIX system, except by very special arrangement
that is simply not relevant for this discussion.  (Privileged
processes can do just about anything at all, and cooperating
processes can have a parent modify the environment based on requests
from a child process.  Neither of these situations holds for normal
UNIX programs.)