WCTOMB(3) BSD Library Functions Manual WCTOMB(3)
wctomb -- converts a wide character to a multibyte character
Standard C Library (libc, -lc)
wctomb(char * s, const wchar_t wchar);
The wctomb() converts the wide character wchar to the corresponding multibyte character, and stores it in the array pointed to by s.
wctomb() may store at most MB_CUR_MAX bytes in the array.
In state-dependent encoding, wctomb() may store the special sequence to change the conversion state before an actual multibyte character into
the array pointed to by s. If wchar is a nul wide character ('