gistfile1.rb

##
## SERVER (config.ru)
## Start with: thin  start -V -R config.ru

app = proc do |env|
  [
    200,
    {
      'Content-Type' => 'text/html',
      'Content-Length' => '2'
    },
    ['hi']
  ]
 end

 run app

##
## CLIENT
##

require 'socket'

socket = TCPSocket.new('0.0.0.0', 3000)
socket.write "GET /first HTTP/1.1\r\nConnection: keep-alive\r\n\r\n"
socket.flush
socket.write "GET /second HTTP/1.1\r\nConnection: close\r\n\r\n"
socket.flush
response = socket.read
socket.close