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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"venv base path does not resolve symlinks using realpath()","articleBody":"It seems there is a bug in venv (and a similar one in virtualenv) where the \"base\" path in pyvenv.cfg is set incorrectly.  If Python is installed in a non-standard folder, e.g. /usr/local/python-X.Y.Z and then symlinked into /usr/local/bin/python3, the venv package does not work correctly.  I believe the source of the trouble is the setting of \"home\" variable.  Specifically, this line:\r\n```\r\ndirname, exename = os.path.split(os.path.abspath(executable))\r\n```\r\nThe `dirname` result is used to set \"home\".  If the executable path is /usr/local/bin/python3 (actually a symlink to /usr/local/python-X.Y.Z/bin/python3), the \"home\" should not be set to /usr/local.  Changing the above line (in the `ensure_directories()`) function to:\r\n```\r\ndirname, exename = os.path.split(os.path.realpath(executable))\r\n```\r\nThis fixes the problem.  I believe this is consistent with what the getpath.py module in Python does.\r\n\r\nI noticed with problem when running the most recent Debian OS, version 12.  It includes Python 3.11 and therefore /usr/lib/python3.11 exists.  With the above bug, the venv tries to use /usr/lib/python3.11 as the sys.path.  Importing the `struct` module fails with the mysterious error:\r\n```\r\n\u003e\u003e\u003e import struct\r\nTraceback (most recent call last):\r\n  File \"\u003cstdin\u003e\", line 1, in \u003cmodule\u003e\r\n  File \"/usr/lib/python3.11/struct.py\", line 13, in \u003cmodule\u003e\r\n    from _struct import *\r\nModuleNotFoundError: No module named '_struct'\r\n```\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-115237\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/nascheme","@type":"Person","name":"nascheme"},"datePublished":"2023-06-23T18:25:34.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":25},"url":"https://github.com/106045/cpython/issues/106045"}