errFatal(local.RegisterSingleHandler(handlerTest, func(payload []byte) ([]byte, *RemoteErr) {
		t.Log("1: server payload: ", len(payload), "bytes.")
		return append([]byte{}, payload...), nil
	}))
	// 2: Return as error
	errFatal(local.RegisterSingleHandler(handlerTest2, func(payload []byte) ([]byte, *RemoteErr) {
		t.Log("2: server payload: ", len(payload), "bytes.")
		err := RemoteErr(payload)
		return nil, &err
	}))

	remote := grid.Managers[1]

	errFatal(local.RegisterSingleHandler(handlerTest, func(payload []byte) ([]byte, *RemoteErr) {
		t.Log("1: server payload: ", len(payload), "bytes.")
		return append([]byte{}, payload...), nil
	}))
	// 2: Return as error
	errFatal(local.RegisterSingleHandler(handlerTest2, func(payload []byte) ([]byte, *RemoteErr) {
		t.Log("2: server payload: ", len(payload), "bytes.")
		err := RemoteErr(payload)
		return nil, &err
	}))

	resp := lockRPCLock.NewResponse()
	success, err := l.ll.Lock(context.Background(), *args)
	if err == nil && !success {
		return l.makeResp(resp, errLockConflict)
	}
	return l.makeResp(resp, err)
}

// UnlockHandler - releases the acquired lock.
func (l *lockRESTServer) UnlockHandler(args *dsync.LockArgs) (*dsync.LockResp, *grid.RemoteErr) {
	resp := lockRPCUnlock.NewResponse()

func NewRemoteErrString(msg string) *RemoteErr {
	r := RemoteErr(msg)
	return &r
}

func (r RemoteErr) Error() string {
	return string(r)
}

// Is returns if the string representation matches.
func (r *RemoteErr) Is(other error) bool {
	if r == nil || other == nil {
		return r == other
	}
	var o RemoteErr
	if errors.As(other, &o) {
		return r == &o
	}

func (s *peerRESTServer) GetLocksHandler(_ *grid.MSS) (*localLockMap, *grid.RemoteErr) {
	res := globalLockServer.DupLockMap()
	return &res, nil
}

// DeletePolicyHandler - deletes a policy on the server.
func (s *peerRESTServer) DeletePolicyHandler(mss *grid.MSS) (np grid.NoPayload, nerr *grid.RemoteErr) {
	objAPI := newObjectLayerFn()
	if objAPI == nil {

	defer p.Recycle()
	return s.RenameDataHandler(&p.RenameDataHandlerParams)
}

// RenameFileHandler - rename a file from source to destination
func (s *storageRESTServer) RenameFileHandler(p *RenameFileHandlerParams) (grid.NoPayload, *grid.RemoteErr) {
	if !s.checkID(p.DiskID) {
		return grid.NewNPErr(errDiskNotFound)
	}

The server handler function has this signature: `type SingleHandlerFn func(payload []byte) ([]byte, *RemoteErr)`.

Sample handler:
```go
    handler :=  func(payload []byte) ([]byte, *grid.RemoteErr) {
        // Do something with payload
        return []byte("response"), nil
    }

    err := manager.RegisterSingleHandler(grid.HandlerDiskInfo, handler)
```

	start := time.Now()
	defer func() {
		if debugPrint {
			fmt.Println("Mux", m.ID, "Handler took", time.Since(start).Round(time.Millisecond))
		}
		if r := recover(); r != nil {
			gridLogIf(ctx, fmt.Errorf("grid handler (%v) panic: %v", msg.Handler, r))
			err := RemoteErr(fmt.Sprintf("handler panic: %v", r))
			handlerErr = &err
		}

		// Register a single handler which echos the payload.
		errFatal(remote.RegisterSingleHandler(handlerTest, func(payload []byte) ([]byte, *RemoteErr) {
			defer PutByteBuffer(payload)
			return append(GetByteBuffer()[:0], payload...), nil
		}))
		errFatal(rpc.Register(remote, func(req *testRequest) (resp *testResponse, err *RemoteErr) {
			return &testResponse{
				OrgNum:    req.Num,
				OrgString: req.String,
				Embedded:  *req,
			}, nil
		}))

	"strings"
	"sync"
	"time"

	"github.com/gobwas/ws"
	"github.com/gobwas/ws/wsutil"
)

// ErrDisconnected is returned when the connection to the remote has been lost during the call.
var ErrDisconnected = RemoteErr("remote disconnected")

const (
	// minBufferSize is the minimum buffer size.
	// Buffers below this is not reused.
	minBufferSize = 1 << 10

	// defaultBufferSize is the default buffer allocation size.