Failed to write any content to multiple files using the multiprocessing module from python3.4

readme.md

Environment:

• uname -a to check OS: Linux NAME 4.9.0-11-amd64 #1 SMP Debian 4.9.189-3+deb9u1 (2019-09-20) x86_64 GNU/Linux
• Python version: Python 3.4.1 |Anaconda 2.1.0 (64-bit)| (default, Sep 10 2014, 17:10:18) (a 3rd party module requires py3.4)

Behaviour:

• When trying to write logs in each process, e.g. one log file for each process, files can be created but no content is written.

Debug:

• No expected errors in worker function
• Failed to write even in single-processing or just call the function without multiprocessing module

Solution:

• add file_handle.flush() after each file_handle.write('some content'). See https://stackoverflow.com/a/28326928/6769366 for details.