use of undeclared identifier 27 o u16text 27

1#include <iostream>
2#include <fcntl.h>
3#include <io.h>
4#include <stdio.h>
5
6int main() {
7    _setmode(_fileno(stdout), 0x00020000); // _O_U16TEXT
8    std::wcout << L"Русский текст\n";
9}
10