when they find 8-bit characters. Previously, they included `ascii' in a
multibyte buffer and `unknown' in a unibyte buffer.
-*** The functions `set-buffer-modified', `string-as-multibyte' and
+*** The functions `set-buffer-multibyte', `string-as-multibyte' and
`string-as-unibyte' change the byte sequence of a buffer or a string
if it contains a character from the `eight-bit-control' character set.