Robo xexelento que executa comando

dibot.rb

require 'rubygems'
require 'xmpp4r-simple'

# gem install xmpp4r-simple

include Jabber
#Jabber::debug = true

jid = 'email@gmail.com'
pass = 'secret'

jabber = Simple.new(jid, pass)
loop do
  messages = jabber.received_messages
  messages.each do |message|
    next unless message.type == :chat

    body = message.body

    result = "oi?"
    if body.start_with?("$")
      process = IO.popen(body.gsub("$", "").strip)
      result = process.readlines
    end

    puts "#{message.from}: #{body}"
    puts "#{result}\n"

    jabber.deliver(message.from, result)
  end

  sleep 1
end