unsigned long GetOpenFileSize(char* ss)
{
    DWORD fp=0;
    HANDLE a;

    a=CreateFile(ss, GENERIC_READ, 0, NULL,
                 OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0 );
    if (a!=INVALID_HANDLE_VALUE)
    {
        fp = GetFileSize(a, NULL);
        CloseHandle(a);
    }

    return fp;
}