Python multiprocessing not calling function

Question

I'm trying to get this code to work, and it looks like update isn't getting called. Nothing is printed to the console with this code, why?

from multiprocessing import Process

def update():
    print("hi")

if __name__ == '__main__':
    p = Process(target=update, args=())
    p.start()
    p.join()

Stop splitting hairs with the answers you have and run it from the command line. It works and prints "hi" — Rolf of Saxony, May 19 '17 at 17:00
**how are you running the code?** It is likely you are using a python environment that overrides `sys.stdout` to catch the output which multiprocessing skips over. — Tadhg McDonald-Jensen, May 19 '17 at 17:04

score 3 · Accepted Answer · edited May 23 '17 at 12:34

3

Run your program from the command line, python idle doesn't deal with this correctly as detailed here

edited May 23 '17 at 12:34

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answered May 19 '17 at 16:53

pointerless

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ErvingGoffman · Answer 2 · 2017-05-19T16:58:11.113

0

Sorry for the stupid answer, but maybe you do not have time to see the output in stdout? Try running the script from the command line, like this: c:\<script location>\script.py

UPD: riscnotcisc said true.

edited May 19 '17 at 16:58

answered May 19 '17 at 16:53

ErvingGoffman

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I'm running in spyder's ipython console, which logs print statements – yellowedhare May 19 '17 at 16:54

Python multiprocessing not calling function

2 Answers2

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