STL and UTF-8 file input/output. How to do it?

Question

I use wchar_t for internal strings and UTF-8 for storage in files. I need to use STL to input/output text to screen and also do it by using full Lithua

Answer 1

Well, after some testing I figured out that FILE is accepted for _iobuf (in the w*fstream constructor). So, the following code does what I need.

#include 
#include 
#include 
#include 
//For writing
    FILE* fp;
    _wfopen_s (&fp, L"utf-8_out_test.txt", L"w");
    _setmode (_fileno (fp), _O_U8TEXT);
    wofstream fs (fp);
    fs << L"ąfl";
    fclose (fp);
//And reading
    FILE* fp;
    _wfopen_s (&fp, L"utf-8_in_test.txt", L"r");
    _setmode (_fileno (fp), _O_U8TEXT);
    wifstream fs (fp);
    wchar_t array[6];
    fs.getline (array, 5);
    wcout << array << endl;//For debug
    fclose (fp);

This sample reads and writes legit UTF-8 files (without BOM) in Windows compiled with Visual Studio 2k8.

Can someone give any comments about portability? Improvements?