aria2

aria2 - a simple utility for downloading files.

1. Disclaimer
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This program comes with no warranty.
You must use this program at your own risk.

2. About aria2
--------------
aria2 has segmented downloading engine in its core. By segmented downloading,
it can download files very much faster than ordinary browsers.

aria2 is in very early development stage. Currently it has following features:
* HTTP/HTTPS GET support
* HTTP Proxy support
* HTTP BASIC authentication support
* HTTP Proxy authentication support
* FTP support(active, passive mode)
* FTP through HTTP proxy(GET command or tunneling)
* Segmented download
* Cookie support(currently aria2 ignores "expires")
* It can run as a daemon process.
* BitTorrent protocol support

3. How to build
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$ ./configure
$ make

The executable is aria2c in src directory.

4. Dependency
-------------
In order to enable HTTPS support, you need GNUTLS or OpenSSL.
In order to enable BitTorrent support, you need GCRYPT(if you choose GNUTLS)
or OpenSSL.

GNUTLS has precedence over OpenSSL if both libraries are installed.

5. BitTorrrent
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The filename of the downloaded file is determined as follows:

single-file mode:
If "name" key is present in .torrent file, filename is the value of "name"
key. Otherwise, filename is the basename of .torrent file appended by
".file". For example, .torrent file is "test.torrrent", then filename is
"test.torrent.file".
The directory to store the downloaded file can be specified by -d option.
multi-file mode:
The complete directory/file structure mentioned in .torrent file is
created.
The directory to store the top directory of downloaded files can be
specified by -d option.

In both mode, aria2 needs at least 2 times more disk space than the file size
itself because it creates complete temporary file.

Note:
* -o option is used to change the filename of downloaded .torrent file.
* This version only supports compact peers list format.
* The ports aria2c uses are 6881-6999.
* The maximum number of peers is 55.