towlower function — Converts a wide character to lowercase
wint_t towlower(wint_t wc)
The towlower function maps the wide character wc to lowercase. If iswupper(wc) is false, or if wc has no lowercase mapping, wc is returned unchanged.
towlower
wc
iswupper(wc)
towctrans function, towupper function, tolower in <cctype>
tolower
<cctype>