emacs una parte del texto solo leído

(defun make-region-read-only (start end)
  (interactive "*r")
  (let ((inhibit-read-only t))
    (put-text-property start end 'read-only t)))

(defun make-region-read-write (start end)
  (interactive "*r")
  (let ((inhibit-read-only t))
    (put-text-property start end 'read-only nil)))
Repulsive Rhinoceros