#15543: additional link in subprocess docs.

Patch by Chris Jerdonek.

Doc/library/subprocess.rst

@@ -290,7 +290,8 @@ default values. The arguments that are most commonly needed are:
 
    If *universal_newlines* is ``True``, the file objects *stdin*, *stdout*
    and *stderr* will be opened as text streams in :term:`universal newlines`
-   mode using the encoding returned by :func:`locale.getpreferredencoding`.
+   mode using the encoding returned by
+   :func:`locale.getpreferredencoding(False) <locale.getpreferredencoding>`.
    For *stdin*, line ending characters ``'\n'`` in the input will be converted
    to the default line separator :data:`os.linesep`.  For *stdout* and
    *stderr*, all line endings in the output will be converted to ``'\n'``.