+.Bf Em
+The
+.Bx 4.4
+.Dq rune
+functions have been deprecated in favour of the
+.Tn ISO
+C99 extended multibyte and wide character facilities
+and should not be used in new applications.
+.Ef
+Consider working with wide characters instead, and using
+.Xr wcschr 3 ,
+.Xr wcsrchr 3 ,
+and
+.Xr wcsstr 3
+instead of these functions.
+.Pp