doc: /* Return a multibyte string with the same individual bytes as STRING.
If STRING is multibyte, the result is STRING itself.
Otherwise it is a newly created string, with no text properties.
+
If STRING is unibyte and contains an individual 8-bit byte (i.e. not
-part of a multibyte form), it is converted to the corresponding
-multibyte character of charset `eight-bit-control' or `eight-bit-graphic'. */)
+part of a correct utf-8 sequence), it is converted to the corresponding
+multibyte character of charset `eight-bit'.
+See also `string-to-multibyte'. */)
(string)
Lisp_Object string;
{
Otherwise it is a newly created string, with no text properties.
If STRING is unibyte and contains an 8-bit byte, it is converted to
-the corresponding multibyte character of charset `eight-bit'. */)
+the corresponding multibyte character of charset `eight-bit'.
+
+This differs from `string-as-multibyte' by converting each byte of a correct
+utf-8 sequence to an eight-bit character, not just bytes that don't form a
+correct sequence. */)
(string)
Lisp_Object string;
{