In some conditions the standard streams will be None or closed in the child process (for example if using "pythonw" instead of "python" on Windows). Avoid failing with a non-0 exit code in those conditions.
Report and initial patch by poxthegreat.
(cherry picked from commit e756f66c83)
Co-authored-by: Antoine Pitrou <pitrou@free.fr>
* Make error message more informative
Replace assertions in error-reporting code with more-informative version that doesn't cause confusion over where and what the error is.
* Additional clarification + get travis to check
* Change from SystemError to TypeError
As suggested in PR comment by @pitrou, changing from SystemError; TypeError appears appropriate.
* NEWS file installation; ACKS addition (will do my best to justify it by additional work)
* Making current AssertionErrors in multiprocessing more informative
* Blurb added re multiprocessing managers.py, queues.py cleanup
* Further multiprocessing cleanup - went through pool.py
* Fix two asserts in multiprocessing/util.py
* Most asserts in multiprocessing more informative
* Didn't save right version
* Further work on multiprocessing error messages
* Correct typo
* Correct typo v2
* Blasted colon... serves me right for trying to work on two things at once
* Simplify NEWS entry
* Update 2017-08-18-17-16-38.bpo-5001.gwnthq.rst
* Update 2017-08-18-17-16-38.bpo-5001.gwnthq.rst
OK, never mind.
* Corrected (thanks to pitrou) error messages for notify
* Remove extraneous backslash in docstring.
* bpo-24484: Avoid race condition in multiprocessing cleanup
The finalizer registry can be mutated while inspected by multiprocessing
at process exit.
* Use test.support.start_threads()
* Add Misc/NEWS
* multiprocessing: open file with closefd=False to avoid ResourceWarning
* _test_multiprocessing: open file with O_EXCL to detect bugs in tests (if a
previous test forgot to remove TESTFN)
* test_sys_exit(): remove TESTFN after each loop iteration
Initial patch written by Serhiy Storchaka.
