X File

From GiderosMobile
Revision as of 05:36, 7 December 2020 by MoKaLux (talk | contribs)

Supported platforms: Platform android.pngPlatform ios.pngPlatform mac.pngPlatform pc.pngPlatform html5.pngPlatform winrt.pngPlatform win32.png
Available since: Gideros 2011.6

Description

A file object is usually returned by io.open used to manipulate (read and write) files in lua.

NOTE: this page and other related file methods use an X before the name because wiki forbids creating pages starting with file

Examples

--function to copy file
local function copy(src, dst)
	local srcf = io.open(src, "rb")
	local dstf = io.open(dst, "wb")

	local size = 2^13 -- good buffer size (8K)
	while true do
		local block = srcf:read(size)
		if not block then break end
		dstf:write(block)
	end
	srcf:close()
	dstf:close()
end

--function to check if file exists
local function exists(file)
	local f = io.open(file, "rb")
	if f == nil then return false end
	f:close() return true
end

--usage
if not exists("|D|database.db") then
	copy("database.db", "|D|database.db")
end

Methods

file:close closes file
file:flush saves any written data to file
file:lines returns an iterator function
file:read reads file according to given formats, returns read values or nil
file:seek sets file seek pos
file:write writes strings or numbers to file

Events

Constants