Lua

Get a Remote FTP File's Size by Name

Demonstrates the Chilkat Ftp2.GetSizeByName method, which returns the size in bytes of a named file in the current remote directory as a 32-bit integer. The only argument is the filename — a name, not a path. It returns -1 when the file is not found or the size cannot be obtained.

Background: This is the direct way to get one file's size when you already know its name, typically via a SIZE command — no full directory listing required. Because the result is 32-bit, it cannot represent files past about 2 GB; use GetSizeStrByName for large files. The argument must be a bare filename in the current directory, so ChangeRemoteDir to the right place first.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the Ftp2.GetSizeByName method, which returns the size in bytes of a named file in
-- the current remote directory as a 32-bit integer.  The only argument is the filename (a name,
-- not a path).

local ftp = chilkat.Ftp2.new()

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

-- Normally you would not hard-code the password in source.  You should instead obtain it
-- from an interactive prompt, environment variable, or a secrets vault.
ftp.password = "myPassword"

local success = ftp:connect()
if not success then
    print(ftp.last_error_text)
    return
end

success = ftp:change_remote_dir("public_html")
if not success then
    print(ftp.last_error_text)
    return
end

-- Returns -1 when the file is not found or the size cannot be obtained.  For files that may
-- exceed 2 GB, use GetSizeStrByName (returns a decimal string).
local fileSize = ftp:get_size_by_name("report.pdf")
if fileSize < 0 then
    print("File not found, or size unavailable.")
    return
end

print("report.pdf is " .. fileSize .. " bytes")

success = ftp:disconnect()
if not success then
    print(ftp.last_error_text)
    return
end