master_rpc.go

func (mr *Master) Register(args *RegisterArgs, _ *struct{}) error {
	mr.Lock()
	defer mr.Unlock()
	debug("Register: worker %s\n", args.Worker)
	mr.workers = append(mr.workers, args.Worker)
	go func() {
		mr.registerChannel <- args.Worker
	}()
	return nil
}

func (mr *Master) Shutdown(_, _ *struct{}) error {
	debug("Shutdown: registration server\n")
	close(mr.shutdown)
	mr.l.Close()
	return nil
}