function quit() {
        //  Closes the connection to the POP3 server, deleting
        //  any msgs marked as deleted.

        if(!isset($this->FP))
        {
            $this->ERROR = "POP3 quit: " . _("connection does not exist");
            return false;
        }
        $fp = $this->FP;
        $cmd = "QUIT";
        fwrite($fp,"$cmd\r\n");
        $reply = fgets($fp,$this->BUFFER);
        $reply = $this->strip_clf($reply);
        if($this->DEBUG) { @error_log("POP3 SEND [$cmd] GOT [$reply]",0); }
        fclose($fp);
        unset($this->FP);
        return true;
    }