if I have a thread that never exists, what is the cleanest way to shut down the main script?

Three ways

  1. detach the never ending thread.

    When the main thread terminates, you won't get the warning.

  2. use a signal handler (to catch ^C) in the main thread to set a shared flag that the never ending thread monitors regularly, and then join the never ending thread from the signal handler before terminating.

    The disadvantage of this is that you need to ensure that and reads or attaches in your never-ending thread timeout occasionally, otherwise you will never check the shared flag until you receive something.

    That means using non-blocking IO for sockets.

  3. Faff around with per-thread signal handlers and use a signal handler in the main thread to send a kill signal to the never ending thread.

    More complicated and no real advantage over using a shared flag, as the thread handler won't respond to the kill signal if it is processing a blocking opcode like read or recv.

Which is more appropriate to your situation will depend upon how your app is currently coded?

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In reply to Re: Exiting a script with an 'infinitely looping' thread by BrowserUk
in thread Exiting a script with an 'infinitely looping' thread by markseger

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