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()

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
		}

	"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.

		cmdLines = append(cmdLines, ep.CmdLine)
	}
	scfg.CmdLines = cmdLines
	return scfg
}

func (s *bootstrapRESTServer) VerifyHandler(params *grid.MSS) (*ServerSystemConfig, *grid.RemoteErr) {
	return getServerSystemCfg(), nil
}

var serverVerifyHandler = grid.NewSingleHandler[*grid.MSS, *ServerSystemConfig](grid.HandlerServerVerify, grid.NewMSS, func() *ServerSystemConfig { return &ServerSystemConfig{} })