in reply to Getting back control..to main script
Use exec instead of system. (Click on the links for documentation).
Update: I forgot to include that this only works in combination with fork. For a nice PM node discussing how to use fork and exec together to get back control immediately after starting a child process see Fork and exec. This chapter that O'Reilly has posted from one of their books, has some good examples: see 10.10 Forking/Spawning Child Processes
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