return &fakeNs{closed: &atomic.Bool{}, fd: fd, inode: inode}
}

// Fd returns the file descriptor
func (f *fakeNs) Fd() uintptr {
	return f.fd
}

func (f *fakeNs) Inode() uint64 {
	return f.inode
}

// Close simulates closing the file descriptor and returns nil for no error
func (f *fakeNs) Close() error {
	f.closed.Store(true)
	return nil
}

func fakeFs() fs.FS {

	return
}

// ErrClientClosed returned when *Client is closed.
var ErrClientClosed = errors.New("rest client is closed")

// Call - make a REST call with context.
func (c *Client) Call(ctx context.Context, method string, values url.Values, body io.Reader, length int64) (reply io.ReadCloser, err error) {
	switch atomic.LoadInt32(&c.connected) {
	case closed:
		// client closed, this is usually a manual process

	}
}

// send the message. msg.Seq and msg.MuxID will be set
func (m *muxClient) send(msg message) error {
	m.respMu.Lock()
	defer m.respMu.Unlock()
	if m.closed {
		return errors.New("mux client closed")
	}
	return m.sendLocked(msg)
}

// sendLocked the message. msg.Seq and msg.MuxID will be set.
// m.respMu must be held.
func (m *muxClient) sendLocked(msg message) error {

	r.mutex.Lock()
	r.refs++
	r.mutex.Unlock()
}

// Close - this closer implements a special closer
// closes the underlying fd only when the refs
// reach zero.
func (r *RLockedFile) Close() (err error) {
	r.mutex.Lock()
	defer r.mutex.Unlock()

	if r.refs == 0 {
		return os.ErrInvalid
	}

	r.refs--
	if r.refs == 0 {
		err = r.File.Close()
	}

	return err
}

// and it is flake-prone to check for closure after calling it, this retries for a bit to make
// sure the netns is closed eventually.
func assertNSClosed(t *testing.T, closed *atomic.Bool) {
	for i := 0; i < 5; i++ {
		if closed.Load() {
			return
		}
		time.Sleep(1 * time.Second)
	}
	t.Fatal("NS not closed")

// the appropriate error will be returned.
type Stream struct {
	// responses from the remote server.
	// Channel will be closed after error or when remote closes.
	// All responses *must* be read by the caller until either an error is returned or the channel is closed.
	// Canceling the context will cause the context cancellation error to be returned.
	responses <-chan Response
	cancel    context.CancelCauseFunc

	if err != nil {
		// Do not leak fd here, close the file properly.
		Fdatasync(jd.file)
		_ = jd.file.Close()

		jd.file = nil // reset to allow subsequent reopen when file/disk is available.
	}
	return err
}

// Close closes the active journal and renames it to read-only for pending
// deletes processing. Note: calling Close on a closed journal is a no-op.
func (jd *tierDiskJournal) Close() error {

	if err != nil {
		return err
	}
	defer xhttp.DrainBody(respBody)
	_, err = waitForHTTPResponse(respBody)
	return toStorageErr(err)
}

// Close - marks the client as closed.
func (client *storageRESTClient) Close() error {
	client.restClient.Close()
	return nil
}

var emptyDiskID = ""

// Returns a storage rest client.

func clear[T ~[]Type | ~map[Type]Type1](t T)

// The close built-in function closes a channel, which must be either
// bidirectional or send-only. It should be executed only by the sender,
// never the receiver, and has the effect of shutting down the channel after
// the last sent value is received. After the last value has been received
// from a closed channel c, any receive from c will succeed without

// the upstream reader after close has been called.
type disconnectReader struct {
	r  io.Reader
	mu sync.Mutex
}

func (d *disconnectReader) Read(p []byte) (n int, err error) {
	d.mu.Lock()
	defer d.mu.Unlock()
	if d.r != nil {
		return d.r.Read(p)
	}
	return 0, errors.New("reader closed")
}

func (d *disconnectReader) Close() error {
	d.mu.Lock()
	d.r = nil