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Lua

Get a Remote File's Size as a String

See more SFTP Examples

Demonstrates the Chilkat SFtp.GetFileSizeStr method, which returns a remote file's size in bytes as a decimal string. The arguments are the remote path (or handle), whether symbolic links are followed, and whether the first argument is a handle.

Background: Returning the size as a string sidesteps integer-width limits entirely, so it is the safe choice for files of any size — multi-gigabyte archives, disk images, database dumps. It is also convenient in programming languages that lack a native 64-bit integer type. When you need to do arithmetic on the value, parse the string; when you only need to display or log it, the string is ready to use.

Chilkat Lua Downloads

Lua
local chilkat = require("chilkat")

-- Demonstrates the SFtp.GetFileSizeStr method, which returns a remote file's size in bytes as a
-- decimal string.  The 1st argument is the remote path (or handle), the 2nd selects whether
-- symbolic links are followed, and the 3rd indicates whether the 1st argument is a handle.

local sftp = chilkat.SFtp.new()

-- Connect, authenticate, and initialize the SFTP subsystem.
local port = 22
local success = sftp:connect("sftp.example.com", port)
if not success then
    print(sftp.last_error_text)
    return
end

-- 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.
local password = "mySshPassword"

success = sftp:authenticate_pw("mySshLogin", password)
if not success then
    print(sftp.last_error_text)
    return
end

success = sftp:initialize_sftp()
if not success then
    print(sftp.last_error_text)
    return
end

-- The 2nd argument (bFollowLinks) selects whether a symbolic link is followed to its target.
-- The 3rd argument (bIsHandle) is false here because the 1st argument is a path, not an
-- open handle.
local bFollowLinks = true
local bIsHandle = false

-- A string return avoids the 32-bit overflow that GetFileSize32 would have for very large files.
local fileSize = sftp:get_file_size_str("subdir/hugefile.dat", bFollowLinks, bIsHandle)
if not sftp.last_method_success then
    print(sftp.last_error_text)
    return
end

print("File size: " .. fileSize .. " bytes")

sftp:disconnect()