1) because on production env, user can change port number. Maybe we can detect port number from process id, but i don't know platform independent way of doing that, yet.

2) So the implemented way in this condition is check server port and waiting for '200 OK'.
    But usually most daemon script does not wait for server actually running.
    
    To apply this always, we need platform independent way. a) we need to detect port number. b) we can not use curl, while some platform might not have curl installed. instead of doing curl, we can implement some signal handler and check server status using signal can be alternative.