LFTP is a sophisticated file transfer program with command line interface. It supports FTP, HTTP, FISH, SFTP, HTTPS and FTPS protocols. GNU Readline library is used for input. BitTorrent protocol is supported as built-in `torrent' command.
Every operation in lftp is reliable, that is any non-fatal error is handled and the operation is retried automatically. So if downloading breaks, it will be restarted from the point automatically. Even if ftp server does not support REST command, lftp will try to retrieve the file from the very beginning until the file is transferred completely. This is useful for dynamic-ip machines which change their IP addresses quite often, and for sites with very bad internet connectivity.
If you exit lftp when some jobs are not finished yet, lftp will move itself to nohup mode in background. The same happens when you have a real modem hangup or when you close an xterm.
lftp has shell-like command syntax allowing you to launch several commands in parallel in background (&). It is also possible to group commands within () and execute them in background. All background jobs are executed in the same single process. You can bring a foreground job to background with ^Z (c-z) and back with command `wait' (or `fg' which is alias to `wait'). To list running jobs, use command `jobs'. Some commands allow redirecting their output (cat, ls, ...) to file or via pipe to external command. Commands can be executed conditionally based on termination status of previous command (&&, ||).
lftp> cat file | gzip > file.gz lftp> get file & lftp> (cd /path && get file) &The first command retrieves file from ftp server and passes its contents to gzip which in turn stores compressed data to file.gz. Other commands show how to start commands or command groups in background.
lftp has builtin mirror which can download or update a whole directory tree. There is also reverse mirror (mirror -R) which uploads or updates a directory tree on server.
There is command `at' to launch a job at specified time in current context, command `queue' to queue commands for sequential execution for current server, and much more.
Other low level stuff supported: ftp proxy, http proxy, ftp over http, opie/skey, fxp transfers, socks.
LFTP supports secure versions of the protocols FTP and HTTP: FTPS (explicit and implicit) and HTTPS. LFTP needs to be linked with an SSL library to support them. GNU TLS and OpenSSL are both supported as SSL backend.
If lftp was compiled with OpenSSL library, then it includes software developed by the OpenSSL Project for use in the OpenSSL Toolkit. (http://www.openssl.org/).
See FEATURES for more detailed list of features.
See the man page lftp(1) for more details.