(file-name-extension): Doc fix.

diff --git a/lisp/files.el b/lisp/files.el
index 16df2661fcf2c7de6584dd7bc7a712c9f6168531..2eaeae5ac8667cb108f50b00d0fe3a7688a79300 100644 (file)
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -3062,6 +3062,7 @@ except that a leading `.', if any, doesn't count."
 (defun file-name-extension (filename &optional period)
   "Return FILENAME's final \"extension\".
 The extension, in a file name, is the part that follows the last `.',
+excluding version numbers and backup suffixes,
 except that a leading `.', if any, doesn't count.
 Return nil for extensionless file names such as `foo'.
 Return the empty string for file names such as `foo.'.