Well, that's easy. I don't think much of that. You would either have to work with threads, or shared memory segments to communicate the state of the variable between the various processes. But, since each of the processes can actually change the variable, you need to implement some form of locking mechanism on the variable.... So, to avoid the "hassle" of locking files (which is really trivial in Unix), you need threads (which don't really work in Perl), or System V shared memory segments (a hassle), and on top of that, you need some form of locking anyway.

-- Abigail