Do not touch sys.path when site is imported and python was started with -S.
Original patch by Carl Meyer, review by Brett Cannon, small doc editions by
yours truly. Fixes #11591.
diff --git a/Doc/library/site.rst b/Doc/library/site.rst
index b77f3cf..4b7a234 100644
--- a/Doc/library/site.rst
+++ b/Doc/library/site.rst
@@ -13,7 +13,11 @@
.. index:: triple: module; search; path
-Importing this module will append site-specific paths to the module search path.
+Importing this module will append site-specific paths to the module search
+path, unless :option:`-S` was used. In that case, this module can be safely
+imported with no automatic modifications to the module search path. To
+explicitly trigger the usual site-specific additions, call the
+:func:`site.main` function.
.. index::
pair: site-python; directory
@@ -114,6 +118,13 @@
.. envvar:: PYTHONUSERBASE
+.. function:: main()
+
+ Adds all the standard site-specific directories to the module search
+ path. This function is called automatically when this module is imported,
+ unless the :program:`python` interpreter was started with the :option:`-S`
+ flag.
+
.. function:: addsitedir(sitedir, known_paths=None)
Adds a directory to sys.path and processes its pth files.