X File

From GiderosMobile
Revision as of 04:56, 1 July 2020 by MoKaLux (talk | contribs) (expanded example)


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

Description

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

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 iterator function to return lines, nil ends
file:read reads file according to given formats, returns read values or nil
file:seek sets file pos, whence="set"|"cur"|"end", defaults "curr",0, returns file pos
file:write writes strings or numbers to file

Events

Constants