_ISUPPER
ctn->ctype |= _ISUPPER;
if (ctn->ctype & (_ISUPPER |_ISLOWER))
ctn->ctype |= (_ISUPPER | _ISALPHA | _ISGRAPH | _ISPRINT);
#define _CTYPE_U _ISUPPER /* Upper */
DEFN_ISTYPE(upper, _ISUPPER)