processing

arg = {...}
if arg[1] == nil then
  arg[1] = "potato"
end

function check()
  g, m, p = rednet.receive("pbp", 5)
  print(m)

end
rednet.open("left")

if arg[1] == "potato" then
  rednet.send(2, "run", "pbp")
  check()
elseif arg[1] == "on" then
  rednet.send(2, "run", "pbp")
  check()
elseif arg[1] == "off" then
  rednet.send(2, "stop", "pbp")
  check()
else
  print("Unknown argument")
end
rednet.close("left")