wcstombs_l
size_t wcstombs_l(char * __restrict, const wchar_t * __restrict, size_t,
len = wcstombs_l(buf, src, bufsiz + 1, loc);
len = wcstombs_l(NULL, src, 0, loc);
return wcstombs_l(s, wcs, n, _current_locale());
sflen = wcstombs_l(NULL, format, 0, loc);
wcstombs_l(sformat, format, sflen + 1, loc);