Thanks for the answers. Perhaps my mistake was trying to solve this problem by using examples from Perl Cookbook :-). All parts for my home-made wheel I found in this book. For my code, I found a solution using IPC::Shareable, by sharing array among processes. Shlock Shunlock for blocking access to array. Which of these modules is the most universal without much low-level work? TheSchwartz POE http://search.cpan.org/~dlux/Parallel-ForkManager-0.7.9/lib/Parallel/ForkManager.pm