// If == 0 no input is expected
		InCapacity int
	}
)

type subHandlerID [32]byte

func makeSubHandlerID(id HandlerID, subRoute string) subHandlerID {
	b := subHandlerID(sha256.Sum256([]byte(subRoute)))
	b[0] = byte(id)
	b[1] = 0 // Reserved
	return b
}

func (s subHandlerID) withHandler(id HandlerID) subHandlerID {
	s[0] = byte(id)
	s[1] = 0 // Reserved
	return s
}

	*f |= flags
}

// Clear one or more flags on f.
func (f *Flags) Clear(flags Flags) {
	*f &^= flags
}

// parse an incoming message.
func (m *message) parse(b []byte) (*subHandlerID, []byte, error) {
	var sub *subHandlerID
	if m.Payload == nil {
		m.Payload = GetByteBuffer()[:0]
	}
	h, err := m.UnmarshalMsg(b)
	if err != nil {
		return nil, nil, fmt.Errorf("read write: %v", err)
	}

}

// Subroute is a connection subroute that can be used to route to a specific handler with the same handler ID.
type Subroute struct {
	*Connection
	trace *tracer
	route string
	subID subHandlerID
}

// String returns a string representation of the connection.
func (c *Connection) String() string {
	return fmt.Sprintf("%s->%s", c.Local, c.Remote)
}

	singleResp         bool
	closed             bool
	stateless          bool
	acked              bool
	init               bool
	deadline           time.Duration
	outBlock           chan struct{}
	subroute           *subHandlerID
	respErr            atomic.Pointer[error]
	clientPingInterval time.Duration
}

// Response is a response from the server.
type Response struct {
	Msg []byte
	Err error
}