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[Python-Dev] why multiprocessing use os._exit

Oleg Broytman phd at phdru.name
Fri Mar 3 07:24:11 EST 2017 
Hello.

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features to Python itself and fixing bugs); if you're having problems
learning, understanding or using Python, please find another forum.
Probably python-list/comp.lang.python mailing list/news group is the
best place; there are Python developers who participate in it; you may
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you for understanding.

   Using os._exit() after fork is documented:
https://docs.python.org/3/library/os.html#os._exit
   and this is exactly what multiprocessing does.

On Fri, Mar 03, 2017 at 12:51:59PM +0800, Tao Qingyun <qingyun.tao at tophant.com> wrote:
> in multiprocessing/forking.py#129, `os._exit` cause child process don't close open
> file. For example:
> 
> ```
>     from multiprocessing import Process
> 
>     def f():
>         global log  # prevent gc close the file
>         log = open("info.log", "w")
>         log.write("***hello world***\n")
> 
>     p = Process(target=f)
>     p.start()
>     p.join()
> 
> ```
> and the `info.log` will be empty. why not use sys.exit ? 
> 
> 
> Thanks

Oleg.
-- 
     Oleg Broytman            http://phdru.name/            phd at phdru.name
           Programmers don't die, they just GOSUB without RETURN.
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