Bug report

Bug description:

An intermittent test failure has been observed on test_support.test_fd_count:

https://buildbot.python.org/#/builders/1380/builds/1423
https://buildbot.python.org/#/builders/1380/builds/626
https://buildbot.python.org/#/builders/1380/builds/84

It's very intermittent - it's occurred 3 times in almost 1400 buildbot runs.

CPython versions tested on:

CPython main branch

Operating systems tested on:

Other

Linked PRs

• gh-124682: Disable test that is prone to intermittent failure on iOS. #124683
• [3.13] gh-124682: Disable test that is prone to intermittent failure on iOS. (GH-124683) #124687