int wctob_l(wint_t c,
            locale_t loc);

wctob_l determines whether c corresponds to a member of the extended character set whose multi-byte character representation is a single byte when in the initial shift state in locale loc.


wctob_l returns EOF if c does not correspond to a multi-byte character with length one in the initial shift state. Otherwise, it returns the single-byte representation of that character as an unsigned char converted to an int.