Free command line email software for linux

LFTP is sophisticated file transfer program with command line interface. LFTP supports FTP, HTTP, FISH, SFTP, HTTPS and FTPS protocols. GNU Readline library is used for input.
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 (&&, ||).
Examples:
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.
LFTP supports IPv6 for both FTP and HTTP protocols. For FTP protocol it uses method described in RFC2428.
Other low level stuff supported: ftp proxy, http proxy, ftp over http, opie/skey, fxp transfers, socks.
If lftp was compiled with ssl support, then it includes software developed by the OpenSSL.
Main features:
- FTP and HTTP protocols support.
- FTP (e.g. TIS FWTK) proxy support.
- HTTP proxy support.
- FTP over HTTP proxy support (hftp).
- HTTPS and FTPS protocols support using OpenSSL library.
- Automatic OPIE/SKEY support in FTP protocol.
- FXP transfers support (between two FTP servers, bypassing client machine).
- FTP listings support: unix-style, NT, EPLF.
- Automatic reconnect and retry of an operation on retriable errors or timeout.
- IPv6 support in both FTP and HTTP.
- FISH protocol support. It uses ssh with no special program on server side.
- SFTP protocol v3 and v4 support.
- HTTP/1.1 keep-alive support.
- Experimental support for SRV DNS records.
- SOCKS support (configure option).
- Modification time preservation (if server can report it).
- `reget and `reput support.
- Built-in mirror and reverse mirror (mirror -R).
- Transfer rate throttling for each connection and for all connections in sum.
- Limit for number of connections to the same site. Interruption of background transfer to do a foreground operation when the limit is reached.
- Socket options tuning: buffer size and maximum segment size.
- Job queueing.
- Job execution at specified time.
- Comprehensive scripting support.
- URL recognition in most operations.
- Readline library is used for input.
- Context sensitive completion.
- Bash-like prompt extensions.
- Launching of local shell commands.
- Suspend support.
- Bookmarks.
- Aliases.
- Saving of last directory on each site. `cd - to go there.
- Copying of files between two servers, e.g. between FTP and HTTP.
- Numerous settings which can be associated with a specific server or a group.
- Paging of remote files using external program.
- `zcat and `zmore support.
- Help for commands.
- Command history saved in a file.
- Transfer status includes rate and ETA.
- File listing cache.
- Background jobs (bash-like).
- Job output redirection to a file or to a program via pipe.
- Conditional commands depending on exit status of previous one.
- Loading of binary modules at run time (configure option).
- `pget to download a file using several connections.
- `mirror can download several files in parallel (--parallel option).
- Slots. Each slot is a separate session, switch using Meta-{1-9} or `slot command. Refer to a slot site using pseudo URL slot:name.

Argtable is an ANSI C library for parsing GNU style command line arguments, as in "foo -abc -o myfile --help --count=7".
Argtable library enables a programs command line syntax to be defined in the source code as an array of argtable structs. The command line is then parsed according to that specification, and the resulting values are returned in those same structs where they are accessible to the main program.
The default parsing, validation, and error reporting routines may be replaced by user-defined callbacks if desired, and new argtable data types may be created to parse user-defined argument types.
The parsing itself is done using GNU getopt and so is 100% GNU compatible.
Enhancements:
- This release adds some additional foolproofing in the arg_xxxn() constructor functions.
- It also fixes a bug in arg_parsearg() that is specific to TI DSP platforms, and a bug in the arg_dbl() constructor that is specific to Solaris platforms.

QSynth project is a fluidsynth GUI front-end application written in C++ around the Qt3 toolkit using Qt Designer.

Eventually it may evolve into a softsynth management application allowing the user to control and manage a variety of command line softsynth but for the moment it wraps the excellent FluidSynth.

FluidSynth is a command line software synthesiser based on the Soundfont specification.

Herrie is a command line music player. It has a split-screen file manager and playlist interface and supports a number of file formats (MP3, Ogg Vorbis, wave, FLAC, etc).

Herrie also has some nice features, including a chroot() function for untrusted setups (remote logins, parties, etc). AudioScrobbler is also implemented using Curl.