Lua

Check if an FTP Listing Entry is a Symbolic Link

Demonstrates the Chilkat Ftp2.GetIsSymbolicLink method, which returns whether a cached directory-listing entry is a symbolic link. The only argument is a zero-based index. This information is available only when the server's listing format reports it.

Background: Symbolic links matter because following one can lead outside the expected directory or into a cycle, so recursive operations often need to identify and skip them. Unlike the file/directory distinction, symlink information is not always present — only listing formats that mark links (typically Unix-style LIST output) expose it, and this returns false when the server does not.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the Ftp2.GetIsSymbolicLink method, which returns whether a cached directory-listing
-- entry is a symbolic link.  The only argument is a zero-based index.  This information is only
-- available when the server's listing format reports it.

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

-- GetDirCount retrieves the directory listing on the first call and returns the number of
-- entries.  A negative return indicates failure.
local n = ftp:get_dir_count()
if n < 0 then
    print(ftp.last_error_text)
    return
end

for i = 0, n - 1 do
    local name = ftp:get_filename(i)
    if ftp:get_is_symbolic_link(i) then
        print("[LINK] " .. name)
    else
        print("       " .. name)
    end
end

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