attack16

-- wait till redstone event, then attack

function detect()
    os.pullEvent("redstone")
    while redstone.getInput(side) do
        turtle.attack()
        sleep(0.5)
    end
end

-- ---------- Running programm ----------
-- Set params
side = "back"

-- repeat loop and never stop
repeat
    result, err = pcall(detect)
    if not result then
        print("Horrible nasty stuff happened...")
        print(err)
        print("Whatever happened... The killing needs to resume!")
    end
until false