git-review-rebase: use fork method when starting multiprocessing manager#25
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…ger. Yann ran into an issue where the python 3.14 multiprocessing Manager seems to refuse to start with a rather cryptic: ValueError: bad value(s) in fds_to_keep Claude thinks this is because on python-3.14 the default method for manager is "forkserver", which doesn't work in the context of an asyncio.thread. A potential fix is to explicitly request the use of the "fork" method. Reported-by: Yann Sionneau <yann.sionneau@vates.tech> Signed-off-by: Quentin Casasnovas <quentin.casasnovas@vates.tech>
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| with multiprocessing.Manager() as manager: | ||
| # Use 'fork' explicitly: forkserver (Python 3.14+ default) fails with -1 fds | ||
| # when Manager() is called from within asyncio.to_thread(). | ||
| ctx = multiprocessing.get_context("fork") |
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I can only say that documentation seems to warn a bit on using context "fork" in a multi threaded code
see https://docs.python.org/3/library/multiprocessing.html#multiprocessing-start-methods
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I had the same issue and it was fixed by this PR as well.
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Yann ran into an issue where the python 3.14 multiprocessing Manager seems to refuse to start with a rather cryptic:
ValueError: bad value(s) in fds_to_keep
Claude thinks this is because on python-3.14 the default method for manager is "forkserver", which doesn't work in the context of an asyncio.thread. The fix is to explicitly request the use of the "fork" method.
Reported-by: Yann Sionneau yann.sionneau@vates.tech