Thanks for replying. I don't think the terminal is being shared among threads in above program. Only main thread is trying to read from terminal. Imagine a situation where you want to create a server where one thread listens for new connections (secondThread in this case) and spawns threads to handle clients (thirdThread in this case), and main thread waits for user's command e.g "exit" to gracefully terminate the server. I understand if there is bug in ActiveState Perl one will have to re-consider the approach otherwise this approach is quite common in real world. thx