Improve the read-file-name doc string slightly

* lisp/minibuffer.el (read-file-name): Note that the semantics of
INITIAL are odd (bug#37883).

diff --git a/lisp/minibuffer.el b/lisp/minibuffer.el
index 917879fb69285c1a275375c70487e545c3d333ba..c9f582394030002bb18f3f45212792bd8b281257 100644 (file)
--- a/lisp/minibuffer.el
+++ b/lisp/minibuffer.el
@@ -3066,7 +3066,10 @@ Fourth arg MUSTMATCH can take the following values:
 - anything else behaves like t except that typing RET does not exit if it
   does non-null completion.
 
-Fifth arg INITIAL specifies text to start with.
+Fifth arg INITIAL specifies text to start with.  It will be
+interpreted as the trailing part of DEFAULT-FILENAME, so using a
+full file name for INITIAL will usually lead to surprising
+results.
 
 Sixth arg PREDICATE, if non-nil, should be a function of one
 argument; then a file name is considered an acceptable completion