[3.7] bpo-33095: Add reference to isolated mode in -m and script option (GH-7764) (GH-16181)

JulienPalard · tirkarthi · web-flow · commit 210dc3bb37ec · 2019-09-16T14:30:33.000+02:00
Attempt to make isolated mode easier to discover via additional inline documentation. Co-Authored-By: Julien Palard <julien@palard.fr>. (cherry picked from commit bdd6945) Co-authored-by: Xtreak <tir.karthi@gmail.com>
diff --git a/Doc/using/cmdline.rst b/Doc/using/cmdline.rst
@@ -100,6 +100,11 @@ source.
    first element will be set to ``"-m"``). As with the :option:`-c` option,
    the current directory will be added to the start of :data:`sys.path`.
 
+   :option:`-I` option can  be used to run the script in isolated mode where
+   :data:`sys.path` contains neither the current directory nor the user's
+   site-packages directory. All :envvar:`PYTHON*` environment variables are
+   ignored, too.
+
    Many standard library modules contain code that is invoked on their execution
    as a script.  An example is the :mod:`timeit` module::
 
@@ -119,6 +124,7 @@ source.
    .. versionchanged:: 3.4
       namespace packages are also supported
 
+.. _cmdarg-dash:
 
 .. describe:: -
 
@@ -130,6 +136,8 @@ source.
    :data:`sys.path`.
 
 
+.. _cmdarg-script:
+
 .. describe:: <script>
 
    Execute the Python code contained in *script*, which must be a filesystem
@@ -148,6 +156,11 @@ source.
    added to the start of :data:`sys.path` and the ``__main__.py`` file in
    that location is executed as the :mod:`__main__` module.
 
+   :option:`-I` option can  be used to run the script in isolated mode where
+   :data:`sys.path` contains neither the script's directory nor the user's
+   site-packages directory. All :envvar:`PYTHON*` environment variables are
+   ignored, too.
+
    .. seealso::
       :func:`runpy.run_path`
          Equivalent functionality directly available to Python code
