Simple TCP server using Ruby

tcp.rb

require 'socket'
require 'thread'

socket = Socket.new Socket::AF_INET, Socket::SOCK_STREAM, Socket::IPPROTO_TCP
socket.setsockopt :SOCKET, :REUSEADDR, 1
socket.bind Addrinfo.tcp('0.0.0.0', 31338)
socket.listen 0

puts "Listen on 0.0.0.0 port 31338"

loop do
  client = socket.accept

  puts "Client connected from #{client[1].inspect}"

  Thread.start(client) do |c|
    begin
      loop do
        data = c[0].gets&.chomp

        if data.nil?
          puts "Client disconnected."
          break
        end

        puts "Received: #{data}"

        c[0].puts "#{data}"
      end
    rescue IOError => e
      puts "Error: #{e.to_s}"
    ensure
      c[0].close
    end
  end
end