socket_state.rb

require 'socket'

TCP_STATES = {
  1 => :established,
  2 => :syn_sent,
  3 => :syn_recv,
  4 => :fin_wait1,
  5 => :fin_wait2,
  6 => :time_wait,
  7 => :close,
  8 => :close_wait,
  9 => :last_ack
}.freeze

def unpack_state(s)
  s.getsockopt(6, 11).unpack('C')[0]
end 

sock = Socket.new(2,1,0)
p TCP_STATES.fetch(unpack_state(sock), 'unknown state')

sock.connect(Addrinfo.tcp('www.google.com', 80))
p TCP_STATES.fetch(unpack_state(sock), 'unknown state')

#sock.puts(%{GET / HTTP/1.1\r\n\r\n})
sock.puts(%{yo!\n\n})
p TCP_STATES.fetch(unpack_state(sock), 'unknown state')

sock.gets('')
p TCP_STATES.fetch(unpack_state(sock), 'unknown state')

sock.shutdown(2)
p TCP_STATES.fetch(unpack_state(sock), 'unknown state')

sock.close