wcrtomb(3) Library Functions Manual wcrtomb(3) wcrtomb - (libc -lc) #include size_t wcrtomb(char *restrict s, wchar_t wc, mbstate_t *restrict ps); s NULL wc (L'\0'). wcrtomb() wc s. *ps s. s NULL wc (L'\0'). wcrtomb() s *ps '\0'. *ps ( ) s. s NULL. wc wcrtomb(buf, L'\0', ps) buf . ps NULL wcrtomb() . MB_CUR_MAX s. s. wcrtomb() s. wc ( ) (size_t) -1 errno EILSEQ. attributes(7). +----+------------------------------------+----------------------------+ || | | +----+------------------------------------+----------------------------+ |wcrtomb()| | MT-Unsafe race:wcrtomb/!ps | | | | | +----+------------------------------------+----------------------------+ C11, POSIX.1-2008. POSIX.1-2001 C99. wcrtomb() LC_CTYPE . NULL ps . mbsinit(3), wcsrtombs(3) 3 . . : . 6.18 8 2026 wcrtomb(3)