Lua

File Existence Check

See more FTP Examples

Testing to see if a file exists on the FTP server. The GetSizeByName method is a convenient way to check if a file exists. It will return -1 if the file does not exist, otherwise it returns the size of the file in bytes. Lua

local chilkat = require("chilkat")

-- This example requires the Chilkat API to have been previously unlocked.
-- See Global Unlock Sample for sample code.

local ftp = chilkat.Ftp2.new()

ftp.hostname = "ftp.example.com"
ftp.username = "username"
ftp.password = "password"

-- Connect and login to the FTP server.
local success = ftp:connect()
if not success then
    print(ftp.last_error_text)
    return
end

-- Set the current remote directory to where the file is located:
success = ftp:change_remote_dir("something")
if not success then
    print(ftp.last_error_text)
    return
end

-- Test to see if the file exists by getting the file size by name.
-- If a -1 is returned, the file does not exist.
local fileSize = ftp:get_size_by_name("test123.txt")
if fileSize < 0 then
    print("file does not exist")
else
    print("file exists and is " .. fileSize .. " bytes in size")
end

success = ftp:disconnect()