//Additional callback functions required for subscribe function subscribe() {                        //**Store the status to a global variable - debug purposes 		$GLOBALS['statusmsg'] = $GLOBALS['statusmsg'] . "SUB-OK|" }  function message($message) {                        //**Store the status to a global variable  - debug purposes 		$GLOBALS['statusmsg']  = "RX-OK|"                         //**Store the received message to a global variable 		$GLOBALS['rcv_message'] =  $message->payload; } 

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