bpo-38602: Add fcntl.F_OFD_XXXX for fcntlmodule (GH-16956)

diff --git a/Doc/library/fcntl.rst b/Doc/library/fcntl.rst
index da39c31..5c172b8 100644
--- a/Doc/library/fcntl.rst
+++ b/Doc/library/fcntl.rst
@@ -36,6 +36,8 @@
 .. versionchanged:: 3.9
    On macOS, the fcntl module exposes the ``F_GETPATH`` constant, which obtains
    the path of a file from a file descriptor.
+   On Linux(>=3.15), the fcntl module exposes the ``F_OFD_GETLK``, ``F_OFD_SETLK``
+   and ``F_OFD_SETLKW`` constants, which working with open file description locks.
 
 The module defines the following functions:
 
diff --git a/Doc/whatsnew/3.9.rst b/Doc/whatsnew/3.9.rst
index b95b099..886c555 100644
--- a/Doc/whatsnew/3.9.rst
+++ b/Doc/whatsnew/3.9.rst
@@ -125,8 +125,15 @@
 :func:`asyncio.run` has been updated to use the new :term:`coroutine`.
 (Contributed by Kyle Stanley in :issue:`34037`.)
 
+fcntl
+-----
+
+Added constants :data:`~fcntl.F_OFD_GETLK`, :data:`~fcntl.F_OFD_SETLK`
+and :data:`~fcntl.F_OFD_SETLKW`.
+(Contributed by Dong-hee Na in :issue:`38602`.)
+
 os
-__
+--
 
 Added :data:`~os.CLD_KILLED` and :data:`~os.CLD_STOPPED` for :attr:`si_code`.
 (Contributed by Dong-hee Na in :issue:`38493`.)