float get_disk_spaces(const char drive_letter, float & total_space, float & used_space)

{

    BOOL fResult;

    unsigned _int64 i64FreeBytesToCaller;

    unsigned _int64 i64TotalBytes;

    unsigned _int64 i64FreeBytes;

    char dir[] = { drive_letter, ':', '\\', '\0'};

    fResult = GetDiskFreeSpaceExA(

        dir,

        (PULARGE_INTEGER)&i64FreeBytesToCaller,

        (PULARGE_INTEGER)&i64TotalBytes,

        (PULARGE_INTEGER)&i64FreeBytes);

    if (fResult)

    {

        /*QMessageBox::about(NULL, "Information",

            ("Get disk space " + QString(dir) + QString::number(i64TotalBytes)));*/

        total_space = (float)i64TotalBytes;

        used_space = (float)(i64TotalBytes - i64FreeBytes);

        return (float)i64TotalBytes;

    }

    else

        QMessageBox::about(NULL, "Information",

            ("Failed to get disk space " + QString(dir)));

    return -;

}