gpt_counter.lua

-- Store a counter that increments each time a player joins

local file = minetest.get_worldpath().."/counter"
local f = io.open(file, "r")
if f==nil then
	counter = 0
else
	counter = tonumber(f:read("*all"))
	f:close()
end

minetest.register_on_joinplayer(function(player)
	counter = counter + 1
	local f = io.open(file, "w")
	f:write(counter)
	f:close()
	minetest.chat_send_all("Player "..player:get_player_name().." is player number "..counter.."!")
end)