multiple processes, private working directories

[Tim Arnold]

I have a bunch of processes to run and each one needs its own working
directory. I'd also like to know when all of the processes are
finished.

(1) First thought was threads, until I saw that os.chdir was process-
global.
(2) Next thought was fork, but I don't know how to signal when each
child is
finished.
(3) Current thought is to break the process from a method into a
external
script; call the script in separate threads.  This is the only way I
can see
to give each process a separate dir (external process fixes that), and
I can
find out when each process is finished (thread fixes that).

Am I missing something? Is there a better way? I hate to rewrite this
method
as a script since I've got a lot of object metadata that I'll have to
regenerate with each call of the script.

thanks for any suggestions,
--Tim Arnold