gistfile1.rb

require 'socket'

class ClientQuitError < RuntimeError; end

port = ARGV.shift || 0 # default is to use the next available port
host = ARGV.shift # default is to bind everything

server = host ? TCPServer.open(host, port) : TCPServer.open(port)

port = server.addr[1]
addrs = server.addr[2..-1].uniq

puts "*** listening on #{addrs.collect{|a|"#{a}:#{port}"}.join(' ')}"

loop do
  socket = server.accept

  Thread.start do # one thread per client
    s = socket

    port = s.peeraddr[1]
    name = s.peeraddr[2]
    addr = s.peeraddr[3]

    puts "*** recieving from #{name}:#{port}"

    begin
      while line = s.gets # read a line at a time
        raise ClientQuitError if line =~ /^die\r?$/
        puts "#{addr} [#{Time.now}]: #{line}"
      end

    rescue ClientQuitError
      puts "*** #{name}:#{port} disconnected"

    ensure
      s.close # close socket on error
    end

    puts "*** done with #{name}:#{port}"
  end

end