hm... depending on your system, this may or may not be a trivial thing to implement. now, i am working on old memories i don't really have any more, but if i remember correctly, a lot of modern OS's will have variable sharing via shmget and shmput and other such LOW level system calls, however depending on the cleaness of the semaphore calls, and the guarantee of atomicity of update, this may become a very difficult thing. We've had very limited success with the IPC shared cache and IPC sharable modules from CPAN, because they do a serialization of data structures, which if you are in a speed quasi-critical enviroment, it becomes a cost prohibitive operation... again, if you must have shared variables (and make sure you understand why you have to have them... they may not be neccessary, and it may be easier to retain state in some other daemon which you poll via a pipe or something along those lines...) the CPAN modules will really help you out.