Remove .begin() from API

NTPClient.cpp

@@ -42,16 +42,6 @@ NTPClient::NTPClient(const char* poolServerName, int timeOffset, int updateInter
   this->_updateInterval = updateInterval;
 }
 
-void NTPClient::begin() {
-  #ifdef DEBUG_NTPClient
-    Serial.println("Begin NTPClient");
-    Serial.print("Start udp connection on port: ");
-    Serial.println(this->_port);
-  #endif
-  this->_udp.begin(this->_port);
-  this->forceUpdate();
-}
-
 void NTPClient::forceUpdate() {
   #ifdef DEBUG_NTPClient
     Serial.println("Update from NTP Server");
@@ -86,8 +76,9 @@ void NTPClient::forceUpdate() {
 }
 
 void NTPClient::update() {
-  unsigned long runtime = millis();
-  if (runtime - this->_lastUpdate >= this->_updateInterval && this->_updateInterval != 0) {
+  if ((millis() - this->_lastUpdate >= this->_updateInterval)     // Update after _updateInterval
+    || this->_lastUpdate == 0) {                                // Update if there was no update yet.
+    if (this->_lastUpdate == 0) this->_udp.begin(this->_port);  // Start _udp if there was no update yet.
     this->forceUpdate();
   }
 }

NTPClient.h

@@ -32,13 +32,6 @@ class NTPClient {
     NTPClient(const char* poolServerName, int timeOffset);
     NTPClient(const char* poolServerName, int timeOffset, int updateInterval);
 
-    /**
-     * Starts the NTPClient
-     * This will create the UDP Socket and get the first update from the NTP server. This must be called after
-     * a WiFi connection is established.
-     */
-    void begin();
-
     /**
      * This should be called in the main loop of your application. By default an update from the NTP Server is only
      * made every 60 seconds. This can be configured in the NTPClient constructor.

examples/Advanced/Advanced.ino

@@ -17,10 +17,6 @@ void setup(){
     delay ( 500 );
     Serial.print ( "." );
   }
-
-  // Start the NTPClient after an WiFi connection is established
-  timeClient.begin();
-
 }
 
 void loop() {

examples/Basic/Basic.ino

@@ -17,10 +17,6 @@ void setup(){
     delay ( 500 );
     Serial.print ( "." );
   }
-
-  // Start the NTPClient after an WiFi connection is established
-  timeClient.begin();
-
 }
 
 void loop() {