Bug report

Bug description:

import subprocess
subprocess.run(['echo', 'hi'], timeout = 0)

# subprocess.TimeoutExpired: Command '['echo', 'hi']' timed out after -0.00010189996100962162 seconds
# subprocess.TimeoutExpired: Command '['echo', 'hi']' timed out after -4.819990135729313e-05 seconds

This is quite unexpected that the measured run-time can be negative

In general, it's unclear in the docs what behavior should have timeout=0. I would propose that it should disable timeout control, and should be equivalent to timeout=None.

But in any case, negative run-times are quite strange :)

CPython versions tested on:

3.12

Operating systems tested on:

WSLv1+Ubuntu24.04

Linked PRs

• gh-133089: Use original timeout value for TimeoutExpired when the func subprocess.run is called with a timeout #133103
• [3.13] gh-133089: Use original timeout value for TimeoutExpired when the func subprocess.run is called with a timeout (GH-133103) #133418