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function ping($host) {   $package = "\x08\x00\x19\x2f\x00\x00\x00\x00\x70\x69\x6e\x67";   /* create the socket, the last '1' denotes ICMP */       $socket = socket_create(AF_INET, SOCK_RAW, 1);      /* set socket receive timeout to 1 second */   socket_set_option($socket, SOL_SOCKET, SO_RCVTIMEO, array("sec" => 1, "usec" => 0));      /* connect to socket */   socket_connect($socket, $host, null);      /* record start time */   list($start_usec, $start_sec) = explode(" ", microtime());   $start_time = ((float) $start_usec + (float) $start_sec);      socket_send($socket, $package, strlen($package), 0);      if(@socket_read($socket, 255)) {       list($end_usec, $end_sec) = explode(" ", microtime());       $end_time = ((float) $end_usec + (float) $end_sec);          $total_time = $end_time - $start_time;              return $total_time;   } else {       return false;   }      socket_close($socket);}echo ping ("www.google.com");