daemons.rb

#!/usr/bin/env ruby

def kill_lingering_daemons
  @daemons && @daemons.each do |pipe|
    Process.kill("KILL", pipe.pid)
  end 
end

def spawn_daemon(command)
  puts command
  @daemons ||= []
  daemon = IO.popen(command)
  @daemons << daemon
  daemon

  sleep 1.5 
end

at_exit do  
  kill_lingering_daemons
end