Info Node: (emacs-lisp-intro.info)Read-only buffer
(emacs-lisp-intro.info)Read-only buffer
A Read-only Buffer
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The asterisk is for the situation when the buffer is a read-only
buffer--a buffer that cannot be modified. If `insert-buffer' is called
on a buffer that is read-only, a message to this effect is printed in
the echo area and the terminal may beep or blink at you; you will not
be permitted to insert anything into current buffer. The asterisk does
not need to be followed by a newline to separate it from the next
argument.