The most simple Buttons API

os.unloadAPI("buttons") -- better safe than sorry - maybe you didn't unload it properly previously
os.loadAPI("buttons")

local running = true
while running do
	local eventTable = {os.pullEvent()}
	-- do something here if you want
end

local running = true
while running do
	local eventTable = {os.pullEvent()}
	buttons.event(eventTable) -- place it before the actual event processing, pass the event table
	-- do something here if you want
	buttons.draw() -- place it after the event processing
	-- if you want to draw anything else, do it here, because buttons.draw() clears the terminal
end

-- load the API here

local buttonExit, buttonHideMe -- it's highly recommended to make these variables local at the beginning of the code

local exit = function() running = false end
local hide = function() buttons.show(buttonHideMe, false) end

-- and the buttons
-- buttons.register returns an ID, that's the reference you use when you want to do something with the button
buttonClose = buttons.register(3, 3, 6, 1, 128, "Exit", exit)
buttonSelfHiding = buttons.register(10, 3, 10, 1, 128, "Hide me!", hide)
--[[ the parameters:
	   - x position
	   - y position
	   - width
	   - height
	   - color (I'll explain later)
	   - text
	   - function pointer
]]

-- here is the loop

os.unloadAPI("buttons")

function convertColor(cBackground, cText)
	local color
	for i = 0, 15 do if 2 ^ i == cBackground then color = i * 16 end end
	for i = 0, 15 do if 2 ^ i == cText then color = color + i end end
	return color
end