EthernetUDP.read()

Description

Reads UDP data from the specified buffer. If no arguments are given, it will return the next character in the buffer. This function can only be successfully called after [UDP.parsePacket()](http://energia.nu/reference/ethernet/ethernet_udpparsepacket/ "Ethernet_UDPParsePacket"){.wikilink}.

Syntax

UDP.read(); UDP.read(packetBuffer, <span class="wikiword">MaxSize</span>);

Parameters

packetBuffer: buffer to hold incoming packets (char) <span class="wikiword">MaxSize</span>: maximum size of the buffer (int)

Returns

char : returns the characters in the buffer

Example

#include <SPI.h>
#include <Ethernet.h>
#include <EthernetUdp.h>
// Enter a MAC address and IP address for your controller below.
// The IP address will be dependent on your local network:
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
IPAddress ip(192, 168, 1, 177);
unsigned int localPort = 8888;      // local port to listen on
// An EthernetUDP instance to let us send and receive packets over UDP
EthernetUDP Udp;
char packetBuffer[UDP_TX_PACKET_MAX_SIZE]; //buffer to hold incoming packet,
void setup() {
  // start the Ethernet and UDP:
  Ethernet.begin(mac,ip);
  Udp.begin(localPort);
}
void loop() {
int packetSize = Udp.parsePacket();
if(packetSize)
{
  Serial.print("Received packet of size ");
  Serial.println(packetSize);
  Serial.print("From ");
  IPAddress remote = Udp.remoteIP();
  for (int i =0; i < 4; i++)
  {
    Serial.print(remote[i], DEC);
    if (i < 3)
    {
      Serial.print(".");
    }
  }
  Serial.print(", port ");
  Serial.println(Udp.remotePort());
    // read the packet into packetBufffer
    Udp.read(packetBuffer,UDP_TX_PACKET_MAX_SIZE);
    Serial.println("Contents:");
    Serial.println(packetBuffer);
}
}

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