Method update

NTPClient.cpp:120–127

}

bool NTPClient::update() {
  if ((millis() - this->_lastUpdate >= this->_updateInterval)     // Update after _updateInterval
    || this->_lastUpdate == 0) {                                // Update if there was no update yet.
    if (!this->_udpSetup || this->_port != NTP_DEFAULT_LOCAL_PORT) this->begin(this->_port); // setup the UDP client if needed
    return this->forceUpdate();
  }
  return false;   // return false if update does not occur
}

bool NTPClient::isTimeSet() const {
  return (this->_lastUpdate != 0); // returns true if the time has been set, else false