General Windows stdout redirection not working

[CrouZ]

BPO	12362
Nosy	@amauryfa, @bitdancer
Superseder	bpo-9390: Error in sys.excepthook on windows when redirecting output of the script

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = <Date 2011-06-19.14:38:53.091>
created_at = <Date 2011-06-19.11:54:28.528>
labels = ['type-bug', 'OS-windows']
title = 'General Windows stdout redirection not working'
updated_at = <Date 2011-06-19.15:59:51.548>
user = 'https://bugs.python.org/CrouZ'

bugs.python.org fields:

activity = <Date 2011-06-19.15:59:51.548>
actor = 'r.david.murray'
assignee = 'none'
closed = True
closed_date = <Date 2011-06-19.14:38:53.091>
closer = 'r.david.murray'
components = ['Windows']
creation = <Date 2011-06-19.11:54:28.528>
creator = 'CrouZ'
dependencies = []
files = []
hgrepos = []
issue_num = 12362
keywords = []
message_count = 5.0
messages = ['138626', '138630', '138634', '138635', '138638']
nosy_count = 3.0
nosy_names = ['amaury.forgeotdarc', 'r.david.murray', 'CrouZ']
pr_nums = []
priority = 'normal'
resolution = 'duplicate'
stage = 'resolved'
status = 'closed'
superseder = '9390'
type = 'behavior'
url = 'https://bugs.python.org/issue12362'
versions = ['Python 3.1', 'Python 2.7']

[CrouZ]

Steps to repeat:

• Create the script foo.py consisting of the line: print("foo")
• Run: foo.py > bar

Behavior:
2.7.2: The file bar is created but empty. Prints the following message on exit:

close failed in file object destructor:
sys.excepthook is missing
lost sys.stderr

3.1.4: The file bar is created but empty. No printouts indicating that something went wrong.

Expected behavior:
All: The file bar has the content foo.

Additional information:
sys.stdout, and probably also sys.stderr, do not appear to be set up properly.
2.7.2: stdout is set to a file but performing any operations on it throws the exception: IOError: [Errno 9] Bad file descriptor
3.1.4: stdout is set to None

Workaround:
All: python foo.py > bar

Used software:
Windows 7 Ultimate SP1 x64 (6.1.7601)
Python 2.7.2 and 3.1.4 installed with the msi-installer including Registering Extensions.

[bitdancer]

The file association for .py is pythonw, which does exactly as you say, intentionally, so as to avoid problems with windows when running a GUI application. My understanding is that this caters to the most common use case on Windows: double clicking a .py file launching a Python GUI application. When running a python script in the console, use 'python', as in your example (or manually change your file association).

[amauryfa]

"The file association for .py is pythonw"
Really? http://docs.python.org/using/windows.html#executing-scripts

[amauryfa]

IMO the cause is actually the same as the one for bpo-9390, i.e. a bug in the Windows console.

[bitdancer]

Ah, I should have known better than to rely on a memory instead of checking, since I don't use Windows much. My apologies.