aria2 is a utility for downloading files\. The supported protocols are HTTP(S), FTP, BitTorrent, and Metalink\. It has a powerful segmented downloading ability, downloading a file from multiple sources and multiple protocols and utilizing your download bandwidth to the maximum\. It supports downloading a file from HTTP(S)/FTP and BitTorrent at the same time, while the data downloaded from HTTP(S)/FTP is uploaded to the BitTorrent swarm\. Using Metalink\'s chunk checksums, aria2 automatically validates chunks of data while downloading a file like BitTorrent\.
In Metalink, BitTorrent download you cannot specify file name\. The file name specified here is only used when the URLs fed to aria2 is done by command line without \-i option, like this: aria2c \-o myfile\.zip http://mirror1/file\.zip http://mirror2/file\.zip
is given, aria2 doesn\'t download a file which already exists but the corresponding \.aria2 file doesn\'t exist\. In HTTP(S)/FTP download, if \-\-auto\-file\-renaming=\fItrue\fR
If false is given, aria2 aborts download when a piece length is different from one in a control file\. If true is given, you can proceed but some download progress will be lost\. Default:
Rename file name if the same file already exists\. This option works only in HTTP(S)/FTP download\. The new file name has a dot and a number(1\.\.9999) appended\. Default:
\fIhttp://host/image[000\-100:2]\.img\fR\. A step counter can be omitted\. If all URIs do not point to the same file, such as the second example above, \-Z option is required\. Default:
Check file integrity by validating piece hash\. This option only affects in BitTorrent downloads and Metalink downloads with chunk checksums\. Use this option to re\-download a damaged portion of a file\. Default:
Validate chunk of data by calculating checkusm while download a file if chunk checksums are provided\. Currently Metalink is the only way to to provide chunk checksums\. Default:
Continue downloading a partially downloaded file\. Use this option to resume a download started by a web browser or another program which downloads files sequentially from the beginning\. Currently this option is only applicable to HTTP(S)/FTP downloads\.
Downloads URIs found in FILE\. You can specify multiple URIs for a single entity: separate URIs on a single line using the TAB character\. Reads input from stdin when
Print file listing of \.torrent or \.metalink file and exit\. In case of \.torrent file, additional information (infohash, piece length, etc) is also printed\.
Set file to download by specifing its index\. You can find the file index using the \-\-show\-files option\. Multiple indexes can be specified by using ",", for example:
\fI3,6\fR\. You can also use "\-" to specify a range:
\fI1\-5\fR\. "," and "\-" can be used together:
\fI1\-5,8,9\fR\. When used with the \-M option, index may vary depending on the query (see \-\-metalink\-* options)\.
In multi file torrent, the adjacent files specified by this option may also be downloaded\. This is by design, not a bug\. A single piece may include several files or part of files, and aria2 writes the piece to the appropriate files\.
is specified, when a file whose suffix is "\.torrent" or content type is "application/x\-bittorrent" is downloaded, aria2 parses it as a torrent file and downloads files mentioned in it\. If
\fImem\fR
is specified, a torrent file is not written to the disk, but is just kept in memory\. If
\fIfalse\fR
is specified, the action mentioned above is not taken\. Default:
Directly read from and write to each file mentioned in \.torrent file\. Use this option if lots of files are listed in \.torrent file and aria2 complains it cannot open files anymore\. Default:
Specify share ratio\. Seed completed torrents until share ratio reaches] RATIO\. I strongly encourages you to specify equals or more than
\fI1\.0\fR
here\. Specify
\fI0\.0\fR
if you intend to do seeding regardless of share ratio\. If \-\-seed\-time option is specified along with this option, seeding ends when at least one of the conditions is satisfied\. Default:
Specify the prefix of peer ID\. The peer ID in BitTorrent is 20 byte length\. If more than 20 bytes are specified, only first 20 bytes are used\. If less than 20 bytes are specified, the random alphabet characters are added to make it\'s length 20 bytes\. Default:
Enable Peer Exchange extension\. If a private flag is set in a torrent, this feature is disabled for that download even if
\fItrue\fR
is given\. Default:
\fItrue\fR
.RE
.PP
\-\-enable\-dht[=\fItrue\fR|\fIfalse\fR]
.RS4
Enable DHT functionality\. If a private flag is set in a torrent, aria2 doesn\'t use DHT for that download even if
\fItrue\fR
is given\. Default:
\fIfalse\fR
.RE
.PP
\-\-dht\-listen\-port=PORT\&...
.RS4
Set UDP listening port for DHT\. Multiple ports can be specified by using ",", for example:
\fI6881,6885\fR\. You can also use "\-" to specify a range:
\fI6881\-6999\fR\. "," and "\-" can be used together\. Default:
\fI6881\-6999\fR
.RE
.PP
\-\-dht\-entry\-point=HOST:PORT
.RS4
Set host and port as an entry point to DHT network\.
.RE
.PP
\-\-bt\-min\-crypto\-level=\fIplain\fR|\fIarc4\fR
.RS4
Set minimum level of encryption method\. If several encryption methods are provided by a peer, aria2 chooses a lowest one which satisfies the given level\. Default:
\fIplain\fR
.RE
.PP
\-\-bt\-require\-crypto=\fItrue\fR|\fIfalse\fR
.RS4
If true is given, aria2 doesn\'t accept and establish connection with legacy BitTorrent handshake(\e19BitTorrent protocol)\. Thus aria2 always uses Obfuscation handshake\. Default:
is specified, when a file whose suffix is "\.metaink" or content type is "application/metalink+xml" is downloaded, aria2 parses it as a metalink file and downloads files mentioned in it\. If
\fImem\fR
is specified, a metalink file is not written to the disk, but is just kept in memory\. If
\fIfalse\fR
is specified, the action mentioned above is not taken\. Default:
is given and several protocols are available for a mirror in a metalink file, aria2 uses one of them\. Use \-\-metalink\-preferred\-protocol option to specify the preference of protocol\. Default:
Print usage and exit\. The help messages are classified in several categories\. For example, type "\-\-help=http" for detailed explanation for the options related to HTTP\. If no matching category is found, search option name using a given word in forward match and print the result\. Available Values:
You can specify multiple URLs\. Unless you specify \-Z option, all URLs must point to the same file or downloading will fail\. You can specify both torrent file with \-T option and URLs\. By doing this, download a file from both torrent swarm and HTTP(S)/FTP server at the same time, while the data from HTTP(S)/FTP are uploaded to the torrent swarm\. Note that only single file torrent can be integrated with HTTP(S)/FTP\.
To pause a download, press Ctrl\-C\. You can resume the transfer by run aria2c with the same argument at the same directory\. You can change URLs as long as they are pointing to the same file\.
Usually, you can resume transfer by just issuing same command(aria2c URL) if the previous transfer is made by aria2\.
.sp
If the previous transfer is made by a browser or wget like sequencial download manager, then use \-c option to continue the transfer(aria2c \-c URL)\.
.sp
.SH"CONTROL FILE"
aria2 uses a control file to keep track the progress of download\. A control file is placed at the same directory of the dowloading file and its filename is the filename of downloading file with "\.aria2" appended\. For example, if you are downloading file\.zip, then the control file should be file\.zip\.aria2\. (There is a exception for this naming convention\. If you are downloading a multi torrent, its control file is the "top directory" name of the torrent with "\.aria2" appended\. The "top directory" name is a value of "name" key in "info" directory in a torrent file\.)
Usually a control file is deleted once download completed\. If aria2 decides that download cannot be resumed(for example, when downloading a file from a HTTP server which doesn\'t support resume), a control file is not created\.
Normally if you lose a control file, you cannot resume download\. But if you have a torrent or metalink with chunk checksums for the file, you can resume the download without a control file by giving \-\-check\-integrity=true option to aria2c in command\-line\.
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.SH"SEEDING DOWNLOADED FILE IN BITTORRENT"
You can seed downloaded file using \-\-check\-integrity=true option\.
User configuration file\. It must be placed under $HOME/\.aria2 and must be named as aria2\.conf\. In each line, there is 1 parameter whose syntax is name=value pair, where name is the long command\-line option name without \fI\-\-\fR prefix\. The lines beginning \fI#\fR are treated as comments\.
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version\.
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This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE\. See the GNU General Public License for more details\.
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You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc\., 51 Franklin Street, Fifth Floor, Boston, MA 02110\-1301 USA
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In addition, as a special exception, the copyright holders give permission to link the code of portions of this program with the OpenSSL library under certain conditions as described in each individual source file, and distribute linked combinations including the two\. You must obey the GNU General Public License in all respects for all of the code used other than OpenSSL\. If you modify file(s) with this exception, you may extend this exception to your version of the file(s), but you are not obligated to do so\. If you do not wish to do so, delete this exception statement from your version\. If you delete this exception statement from all source files in the program, then also delete it here\.
