#include <windows.h>
#include <cstdio>
#include <string>
#include <cwchar>

using namespace std;

// Uses the unicode version of argv[0] to generate an absolute (if necessary) 
// unicode path to a file in the directory this executable is in.
inline wstring generatePath( const wchar_t* p, const wstring& file) {
    const wstring s( p );
    if ( s.find(L"/") != wstring::npos) {
        return s.substr( 0, s.rfind( L"/" ) ) + L"/" + file;
    } else if ( s.find(L"\\") != wstring::npos ) {
        return s.substr( 0, s.rfind( L"\\" ) ) + L"\\" + file;
    } else {
        return file;
    }
}

int main() {
    int argc;
    wchar_t** argv = CommandLineToArgvW( GetCommandLineW(), &argc);
    const wstring file( generatePath( argv[0], L"file.txt") );
    // Write the unicode path to the file specificed by that unicode path
    // so the path can be checked.  File format is UTF-16LE
    FILE* out = _wfopen( file.c_str(), L"wb");
    if (!out) {
        return 1;
    }
    fwprintf(out, L"%c", 0xFEFF);
    fwprintf(out, L"%s", file.c_str());
    fclose(out);
}

// g++ -Wall -Wextra abspath.cpp -o abspath --define _UNICODE