#7301: add the environment variable $PYTHONWARNINGS to supplement the -W
command line option
patch from Brian Curtin
diff --git a/Doc/using/cmdline.rst b/Doc/using/cmdline.rst
index cd5b8b5..7ccf8f0 100644
--- a/Doc/using/cmdline.rst
+++ b/Doc/using/cmdline.rst
@@ -352,6 +352,8 @@
 
       :pep:`230` -- Warning framework
 
+      :envvar:`PYTHONWARNINGS`
+
 
 .. cmdoption:: -x
 
@@ -547,6 +549,12 @@
    value instead of the value got through the C runtime.  Only works on
    Mac OS X.
 
+.. envvar:: PYTHONWARNINGS
+
+   This is the equivalent to the :option:`-W` option. If set to a comma
+   separated string, it is equivalent to specifying :option:`-W` multiple
+   times.
+
 
 Debug-mode variables
 ~~~~~~~~~~~~~~~~~~~~