point from moving into the prompt.
** The minibuffer prompt is now actually inserted in the minibuffer.
This makes it possible to scroll through the prompt, if you want to.
+To disallow this completely (like previous versions of emacs), customize
+the variable `minibuffer-prompt-properties', and turn on the
+`Inviolable' option.
The function minubuffer-prompt-end returns the current position of the
end of the minibuffer prompt, if the minibuffer is current.