iswctype - wide-character classification
int iswctype(wint_t wc, wctype_t desc);
If wc is a wide character having the character property designated by desc (or in other words: belongs to the character class designated by desc), the iswctype() function returns nonzero. Otherwise, it returns zero. If wc is WEOF, zero is returned.
desc must be a character property descriptor returned by the wctype(3) function.
The iswctype() function returns nonzero if the wc has the designated property. Otherwise, it returns 0.
For an explanation of the terms used in this section, see attributes(7).
POSIX.1-2001, POSIX.1-2008, C99.
The behavior of iswctype() depends on the LC_CTYPE category of the current locale.