# File lib/net/ping/icmp.rb, line 26
      def initialize(host=nil, port=nil, timeout=5)
         raise 'requires root privileges' if Process.euid > 0

         @seq = 0
         @bind_port = 0
         @bind_host = nil
         @data_size = 56
         @data = ''

         0.upto(@data_size){ |n| @data << (n % 256).chr }

         @pid  = Process.pid & 0xffff

         super(host, port, timeout)
         @port = nil # This value is not used in ICMP pings.
      end