From d5a6d36223acb571ae4487c8f983e5dcb8dca0e5 Mon Sep 17 00:00:00 2001
From: Zackery Spytz <zspytz@gmail.com>
Date: Sun, 11 Apr 2021 08:17:38 -0600
Subject: [PATCH] bpo-41661: Document os.path.relpath() behavior on Windows
 with different drives

---
 Doc/library/os.path.rst | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Doc/library/os.path.rst b/Doc/library/os.path.rst
index e2f335ee8c3091..4cab3113c9e4e5 100644
--- a/Doc/library/os.path.rst
+++ b/Doc/library/os.path.rst
@@ -366,7 +366,8 @@ the :mod:`glob` module.)
    Return a relative filepath to *path* either from the current directory or
    from an optional *start* directory.  This is a path computation:  the
    filesystem is not accessed to confirm the existence or nature of *path* or
-   *start*.
+   *start*.  On Windows, :exc:`ValueError` is raised when *path* and *start*
+   are on different drives.
 
    *start* defaults to :attr:`os.curdir`.