Lua

Copy Local File Attributes to a Remote SFTP File

Demonstrates the Chilkat SFtp.CopyFileAttr method, which copies supported timestamps and attributes from a local file to a remote item. The arguments are the local file, the remote file (a path or an open handle), and isHandle indicating which form the second argument takes.

Note: This example uses a relative local path, which is resolved against the application's current working directory. Absolute local paths may also be used. Supply the path appropriate to your own environment.

Background: An upload transfers a file's bytes but not necessarily its metadata, so the remote copy may end up with the upload time as its modified time. CopyFileAttr propagates the local file's timestamps and attributes to the remote file, which matters for backups and mirrors where preserving modification times is important — and for incremental sync logic that compares timestamps to decide what changed. The isHandle flag lets you target either a remote path or a file you already have open.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the SFtp.CopyFileAttr method, which copies supported timestamps and attributes
-- from a local file to a remote item.  The 1st argument is the local file, the 2nd is the
-- remote file (a path or an open handle), and the 3rd (isHandle) indicates which.

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

-- Upload a file first.
success = sftp:upload_file_by_name("subdir/report.pdf", "qa_data/report.pdf")
if not success then
    print(sftp.last_error_text)
    return
end

-- Copy the local file's timestamps and attributes onto the remote file.  Because the 2nd
-- argument is a remote path (not an open handle), isHandle is false.
local isHandle = false
success = sftp:copy_file_attr("qa_data/report.pdf", "subdir/report.pdf", isHandle)
if not success then
    print(sftp.last_error_text)
    return
end

print("Attributes copied.")

sftp:disconnect()