testcase for pubsubclient retained

publish.ino

// Reed Switch to MQTT publisher for home
// Andrew Elwell, May 2015

#include <SPI.h>
#include <Ethernet.h>
#include <PubSubClient.h>

byte mac[]    = { 0x00, 0x04, 0xA3, 0x2C, 0x1D, 0xF1 };
byte server[] = { 10, 1, 1, 251 };

//void callback(char* topic, byte* payload, unsigned int length);

EthernetClient ethClient;
PubSubClient client(server, 1883, 0, ethClient);

uint8_t op[4] = { 0x6f, 0x70, 0x65, 0x6e };              // 'open'
uint8_t cl[6] = { 0x63, 0x6c, 0x6f, 0x73, 0x65, 0x64 };  // 'closed'

//int led = 13; // BLINKY THING - cant use if ethernet active

int gate= 2; // Blue -> Green pair
int gateState = 0;
int gatelast = 0;

void setup() { 
 delay( 50 );   // allow some time (50 ms) after powerup and sketch start, for the Wiznet W5100 Reset IC to release and come out of reset.
 
if (Ethernet.begin(mac) == 0)  {
//      Serial.println("Failed to configure Ethernet using DHCP");
      return;
  }
 
// pinMode(led, OUTPUT);
 pinMode(gate, INPUT);           // set pin to input
 digitalWrite(gate, HIGH);       // turn on pullup resistors

//Connect to MQTT
  if (!client.connected())
  {
    client.connect("Etherten01");
    client.publish("etherten/status", "ONLINE");
  }

}

// the loop routine runs over and over again forever:
void loop() {
  gateState = digitalRead(gate);
  if (gateState != gatelast) {
    if (gateState == HIGH) {
      // Trying to set retained, so need the following call
      client.publish("etherten/gate", op, 4, 1);
      // ^^^ not working, as expecting uint8_t rather than char as per the non-retained version below.
      // client.publish("etherten/gate", "open");
    } else {
      //client.publish("etherten/gate", "closed");
      client.publish("etherten/gate", cl, 6, 1);
    }  
  }
  gatelast = gateState ;
 
  client.loop();
}

reedsw_etherten_test.ino: In function 'void loop()':
reedsw_etherten_test:50: error: invalid conversion from 'const char_' to 'uint8_t_'
reedsw_etherten_test:50: error: initializing argument 2 of 'boolean PubSubClient::publish(char_, uint8_t_, unsigned int, boolean)'
reedsw_etherten_test:55: error: invalid conversion from 'const char_' to 'uint8_t_'
reedsw_etherten_test:55: error: initializing argument 2 of 'boolean PubSubClient::publish(char_, uint8_t_, unsigned int, boolean)'

using the 1.0.5 IDE