Method subscribe

nats.go:4884–4891

subscribe is the internal subscribe function that indicates interest in a subject.

(subj, queue string, cb MsgHandler, ch chan *Msg, errCh chan (error), isSync bool, js *jsSub)

// subscribe is the internal subscribe function that indicates interest in a subject.
func (nc *Conn) subscribe(subj, queue string, cb MsgHandler, ch chan *Msg, errCh chan (error), isSync bool, js *jsSub) (*Subscription, error) {
	if nc == nil {
		return nil, ErrInvalidConnection
	}
	nc.mu.Lock()
	defer nc.mu.Unlock()
	return nc.subscribeLocked(subj, queue, cb, ch, errCh, isSync, js)
}

func (nc *Conn) subscribeLocked(subj, queue string, cb MsgHandler, ch chan *Msg, errCh chan (error), isSync bool, js *jsSub) (*Subscription, error) {
	if nc == nil {