`python -m asyncio` returns 0 when failing with ENOTTY in the runner thread

[zvyn]

Bug report

Bug description:

The return code at the end here is 0 when it should be 25 aka ENOTTY:

import subprocess
proc = subprocess.Popen(["./python", "-m", "asyncio"], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
with proc:
    try:
        out, err = proc.communicate()
    finally:
        proc.kill()
proc.returncode

note: I tested this with --disable-gil configured

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux

Linked PRs

• gh-121711: Set -m asyncio return_code to 1 for ENOTTY #121714
• [3.13] gh-121711: Set -m asyncio return_code to 1 for ENOTTY (GH-121714) #121718

[ambv]

Thanks, Milan! ✨ 🍰 ✨