Sharing between threads

[Stephen Touset <stephen@touset.org>]

Hey all. I'm working with a Perl script where I want to break off a
certain part of execution into multiple threads. Right now, I'm
attempting to do a calculation based on two variables, and based on a
certain condition, put them back into a shared array.

Unfortunately, I'm running into a problem. I want the array to be
shared, but I don't want the two variables that the computation is done
on to be shared, since different threads are going to be working
simultaneously on different values of the variables.

I also don't want to join() back threads, so just returning the values
won't work. This is due to the fact that there will be a flag to the
program limiting the number of spawned threads. With my current
implementation, I just make a semaphore with the maximum number of
threads as its argument, and then do a down() before executing each
thread, and an up() when finishing. So no, a join() won't work in this
case, because it would eliminate my ability to accurately and
efficiently limit the number of executing threads at any given time.

Is this at all possible?

-- 
Stephen Touset <stephen@touset.org>