getaddrinfo.rb

#!/usr/bin/env ruby

require 'socket'

$stdout.sync = true
$stderr.sync = true

@lock = Mutex.new

def main
  th  = []
  n   = 300
  err = 0

  for i in 1..n
    th << Thread.new(i) do |i|
      begin
        ip = Socket.getaddrinfo('www.irori.org', nil)
      rescue SocketError => e
        @lock.synchronize do
          err += 1
        end
        puts format("[%6d] %s\n", i, e)
      else
        puts format("[%6d] %s\n", i, ip[0][3])
      end
    end
  end

  th.each {|t| t.join}

  puts RUBY_VERSION
  puts format("failed %d/%d %.2f%%", err, n, err.to_f/n.to_f*100)

  exit 0
end

main if __FILE__ == $PROGRAM_NAME