facemenu-set-read-only

facemenu-set-read-only is an interactive compiled Lisp function in `facemenu.el'.

It is bound to <C-down-mouse-2> <sp> r, <menu-bar> <edit> <props> <sp> r.

(facemenu-set-read-only START END)

Make the region unmodifiable.
This sets the `read-only' text property; it can be undone with
`facemenu-remove-special'.