argparse: Check if stderr is defined before writing to it #101640
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URL: https://github.com/python/cpython/issues/101640
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Bug report
argparsetries to write to stderr inconditionally, even when it'sNone. This is only a problem on Windows. Here:https://github.com/python/cpython/blob/3.11/Lib/argparse.py#L2596-L2600
I detected this when using PyInstaller to create a binary on Windows using
--noconsole, which triggers usingpythonw.exe. In this case,sys.stderr is None.This is similar to #89057
Your environment
Linked PRs
pythonwby dropping stderr writes there #101802