minetest crash script

local worldpath = minetest.get_worldpath()

local gamepath = string.gsub(worldpath, "/worlds/.*", "/games/mineclone/")

local schematics = {}

local ie = minetest.request_insecure_environment()
local pathlist = ie.io.popen("find " .. gamepath .. " -name '*.mts'")
for line in pathlist:lines() do
	table.insert(schematics, line)
end
ie = nil

minetest.register_chatcommand("schematics", {
	description = "dump registrations to file",
	params = "<action>",
	privs = {server = true},
	func = function(_, param)
		if not param or param == "" then return false end

		if param == "check" then
			local outfilepath = worldpath .. "/schematics_check.txt"
			local file = io.open(outfilepath, "w")
			if not file then
				return false, "could not open file for output!"
			end
			local s
			for _, filename in ipairs(schematics) do
				minetest.log("report for ".. filename)
				file:write("report for ", filename, " :\n")
				file:flush()
				minetest.log("written header to ".. outfilepath)
				--s = minetest.read_schematic(filename, {write_yslice_prob = "all"})
				s = minetest.read_schematic(filename, {})
				minetest.log("read schematic ".. filename)
				local seen = {}
				for _, n in ipairs(s.data) do
					if n.param2 ~= 0 then
						minetest.log("node ".. n.name.. " has nonzero param2.")
						file:write("node ", n.name, " has nonzero param2.\n")
					end
					if not seen[n.name] then
						seen[n.name] = 1
						if not minetest.registered_nodes[n.name] then
							if minetest.registered_aliases[n.name] then
								minetest.log("node ".. n.name.. " is an alias.")
								file:write("node ", n.name, " is an alias.\n")
							else
								minetest.log("node ".. n.name.. " is not registered.")
								file:write("node ", n.name, " is not registered.\n")
							end
						end
					end
				end
			end
			file:flush()
			file:close()

		end
		return true, "report written to " .. outfilepath
	end
})