Perl 5.6 saw yet another threading model. So when you get ActivePerl, it has been built with this new threading model that simulates fork() by starting another thread with another Perl interpretter that is given a copy of the running interpretter's state.

No, in my experience, it isn't more than the slightest bit useful. 90% of the simple things I tried failed in strange and scary ways.

If you compile Perl yourself, then you can use the ithreads interface with Perl 5.6. I've heard of people actually doing productive work with it. I've also heard there are a lot of gotchas so you have to work around those.

        - tye (but my friends call me "Tye")