Translate error code into string

void LErr(TCHAR szFunc[] = NULL, DWORD dwErr = 0)
{
    /*
        szFunc ... Function Name
        dwErr ... Error Code (it ccan be obtained by GetLastError() or sth)
    */

    LPVOID lpMsgBuf;
    TCHAR szMsg[4096] = { '\0' };

    FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM |
        FORMAT_MESSAGE_IGNORE_INSERTS, NULL, dwErr,
        MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
        (LPTSTR)&lpMsgBuf, 0, NULL);

    swprintf_s(szMsg, 4096, _T("%s\r\n0x%08X (Dec:%u)"), lpMsgBuf, dwErr, dwErr);

    //MessageBox(NULL, szMsg, NULL, MB_OK);
}