René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"New site.py implementation fails to load .pth files in subprocesses","articleBody":"# Bug report\n\n### Bug description:\n\nAfter https://github.com/python/cpython/pull/149583, `.pth` files are no longer loaded in Python subprocesses, as started with `subprocess.run([sys.executable, …])` and the like.\n\nThe new implementation deliberately ignores `.pth` files in `sys.path` directories that are already known, and Python subprocesses already know all the paths of their parent process. Thus, all `.pth` files in those paths are ignored by subprocesses now.\n\nI specifically noticed this when running `setuptools` in a build subprocess, which now fails to install its `distutils` replacement hack.\n\n### CPython versions tested on:\n\nCPython main branch\n\n### Operating systems tested on:\n\nLinux\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-149888\n* gh-150177\n* gh-150202\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/scoder","@type":"Person","name":"scoder"},"datePublished":"2026-05-14T06:53:35.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":9},"url":"https://github.com/149819/cpython/issues/149819"}