Pylint not suppressing the stdout of C loaded extensions

[willpxxr]

Steps to reproduce

1. Pylint configured to load a module which contains a C extension ie. Pygame, and report in JSON

[MASTER]
extension-pkg-whitelist=pygame
...
[REPORTS]
output-format=json

2. Run Pylint on a file which contains a call to the method containing a C extension.

import pygame
if __name__ == "__main__":
        pygame.init()

pylint main.py > output.json

3. Cat the output and the result should look as follows:

pygame 1.9.6
Hello from the pygame community. https://www.pygame.org/contribute.html
[
    {
        "type": "convention",
        "module": "settings",
        "obj": "",
        "line": 1,
        "column": 0,
        "path": "src/games/space_invaders/settings.py",
        "symbol": "missing-module-docstring",
        "message": "Missing module docstring",
        "message-id": "C0114"
    },
...

Current behavior

Currently Pylint is not suppressing messages written to the stdout of C extensions which get loaded. This results in a report generation which does not follow the json formatting, as it contains anything which may be printed to the stdout by a C extension during analysis.

Expected behavior

Pylint shouldn't print the stdout messages of C extensions being ran during analysis.
ie the report.json should look as follows:

[
    {
        "type": "convention",
        "module": "settings",
        "obj": "",
        "line": 1,
        "column": 0,
        "path": "src/games/space_invaders/settings.py",
        "symbol": "missing-module-docstring",
        "message": "Missing module docstring",
        "message-id": "C0114"
    },
...

pylint --version output

circleci@b0feadac759a:~$ pylint --version
pylint 2.4.4
astroid 2.3.3
Python 3.6.10 (default, Apr 21 2020, 14:40:51)
[GCC 8.3.0]

[willpxxr]

Attached my pylintrc for reference

[PCManticore]

Thanks for the report, definitely makes sense.

[piotr-machura]

Hi, this issue causes problems when using pylint's json output for linting in language servers - in the case of pygame it can be ad-hoc fixed by adding export PYGAME_HIDE_SUPPORT_PROMPT="hide" to the working environment, but it would be great to have a proper fix for other such C extensions.