if err != nil {
		return &fs.PathError{
			Op:   lt.String(),
			Path: f.Name(),
			Err:  err,
		}
	}
	return nil
}

func unlock(f File) error {
	ol := new(syscall.Overlapped)
	err := windows.UnlockFileEx(syscall.Handle(f.Fd()), reserved, allBytes, allBytes, ol)
	if err != nil {
		return &fs.PathError{
			Op:   "Unlock",
			Path: f.Name(),
			Err:  err,
		}
	}
	return nil