Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Marc Aymerich <glicerinu@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Futex hang when running event loop on a separated thread
Date: Tue, 24 Nov 2015 19:37:35 +0100
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On Tue, Nov 24, 2015 at 7:11 PM, Zachary Ware
<zachary.ware+pylist@gmail.com> wrote:
> On Tue, Nov 24, 2015 at 9:46 AM, Marc Aymerich <glicerinu@gmail.com> wrote:
>> if __name__ == '__main__':
>>     loop_container = {}
>>     handler = threading.Thread(target=run_loop, args=(loop_container, ))
>>     handler.start()
>>     try:
>>         time.sleep(10000)
>>     finally:
>>         loop_container['loop'].stop()
>
> loop.stop() must be called from the thread running the loop.  You can
> do this by doing
> `loop_container['loop'].call_soon_threadsafe(loop_container['loop'].stop)`
> from the main thread (untested).
>

Hi Zachary,
nice to know about call_soon_threadsafe!

still it appears to work only if the main thread is in the foreground
(as of calling Thread() with deamon=True), I don't get why it behaves
differently :( maybe it is waiting for other stuff, but no idea how to
confirm this with strace of other means.. i always see the same
'futex(0x7f9a70000c10, FUTEX_WAIT_PRIVATE, 0, NULL'

-- 
Marc