aria2/doc/aria2c.1.txt

ARIA2C(1)
=========
Tatsuhiro Tsujikawa <t-tujikawa@users.sourceforge.net>
:man source: Aria2
:man manual: Aria2 Manual
:man version: 1.9.0a

NAME
----
aria2c - The ultra fast download utility

SYNOPSIS
--------
aria2c ['OPTIONS'] ['URI' | 'MAGNET' | 'TORRENT_FILE' | 'METALINK_FILE']...

DESCRIPTION
-----------

aria2 is a utility for downloading files. The supported protocols are
HTTP(S), FTP, BitTorrent, and Metalink. aria2 can download a file from
multiple sources/protocols and tries to utilize your maximum download
bandwidth. 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.

OPTIONS
-------

Basic Options
~~~~~~~~~~~~~
*-d*, *--dir*=DIR::
  The directory to store the downloaded file.

*-i*, *--input-file*=FILE::
  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 '-' is specified.
  The additional *out* and *dir* options can be specified after each line of
  URIs. This optional line must start with white space(s).
  See *Input File* subsection for details.

*-l*, *--log*=LOG::
  The file name of the log file. If '-' is specified, log is written to
  stdout.

*-j*, *--max-concurrent-downloads*=N::
  Set maximum number of parallel downloads for every static (HTTP/FTP) URL,
  torrent and metalink. See also *-s* and *-C* option.
  Default: '5'

*-V*, *--check-integrity*[='true'|'false']::
  Check file integrity by validating piece hashes.
  This option has effect only in BitTorrent and Metalink downloads with
  chunk checksums.
  Use this option to re-download a damaged portion of a file.
  Default: 'false'

*-c*, *--continue*::
   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.

*-h*, *--help*[=TAG|KEYWORD]::

   The help messages are classified with tags. A tag starts with
   "#". For example, type "--help=#http" to get the usage for the
   options tagged with "#http". If non-tag word is given, print the
   usage for the options whose name includes that word.
   Available Values: '#basic', '#advanced', '#http', '#https', '#ftp',
   '#metalink', '#bittorrent', '#cookie', '#hook', '#file',
   '#xml-rpc', '#experimental', '#all'
   Default: '#basic'

HTTP/FTP Options
~~~~~~~~~~~~~~~~
*--all-proxy*=PROXY::

  Use this proxy server for all protocols.  To erase previously
  defined proxy, use "".  You can override this setting and specify a
  proxy server for a particular protocol using *--http-proxy*,
  *--https-proxy* and *--ftp-proxy* options.  This affects all URLs.
  The format of PROXY is [\http://][USER:PASSWORD@]HOST[:PORT]

*--connect-timeout*=SEC::
  Set the connect timeout in seconds to establish connection to
  HTTP/FTP/proxy server. After the connection is established, this
  option makes no effect and *--timeout* option is used instead.
  Default: '60'

*--dry-run*[='true'|'false']::
  If 'true' is given, aria2 just checks whether the remote file is
  available and doesn't download data. This option has effect on
  HTTP/FTP download.  BitTorrent downloads are canceled if 'true' is
  specified.  Default: 'false'

*--lowest-speed-limit*=SPEED::
  Close connection if download speed is lower than or equal to this
  value(bytes per sec).
  '0' means aria2 does not have a lowest speed limit.
  You can append 'K' or 'M'(1K = 1024, 1M = 1024K).
  This option does not affect BitTorrent downloads.
  Default: '0'

*--max-file-not-found*=NUM::
  If aria2 receives `file not found' status from the remote HTTP/FTP
  servers NUM times without getting a single byte, then force the
  download to fail. Specify '0' to disable this option. This options is
  effective only when using HTTP/FTP servers.
  Default: '0'

*-m*, *--max-tries*=N::
  Set number of tries. '0' means unlimited.
  Default: '5'

*-n*, *--no-netrc*::
  Disables netrc support. netrc support is enabled by default.

*--no-proxy*=DOMAINS::
  Specify comma separated hostnames or domains where proxy should not be
  used.

*-o*, *--out*=FILE::

  The file name of the downloaded file. When *-Z* option is used, this
  option is ignored.

[NOTE]
In Metalink or BitTorrent download you cannot specify file name.
The file name specified here is only used when the URLs fed to aria2
are done by command line without *-i*, *-Z* option. For example:
aria2c -o myfile.zip "http://mirror1/file.zip" "http://mirror2/file.zip"

*--proxy-method*=METHOD::
  Set the method to use in proxy request.  'METHOD' is either 'get' or
  'tunnel'. HTTPS downloads always use 'tunnel' regardless of this
  option.
  Default: 'get'

*-R*, *--remote-time*[='true'|'false']::
  Retrieve timestamp of the remote file from the remote HTTP/FTP
  server and if it is available, apply it to the local file.
  Default: 'false'

*--reuse-uri[='true'|'false']::

  Reuse already used URIs if no unused URIs are left.
  Default: 'true'

*--server-stat-of*=FILE::
  Specify the filename to which performance profile of the servers is
  saved. You can load saved data using *--server-stat-if* option. See
  *Server Performance Profile* subsection below for file format.

*--server-stat-if*=FILE::
  Specify the filename to load performance profile of the servers. The
  loaded data will be used in some URI selector such as 'feedback'.
  See also *--uri-selector* option. See *Server Performance Profile*
  subsection below for file format.

*--server-stat-timeout*=SEC::
  Specifies timeout in seconds to invalidate performance profile of
  the servers since the last contact to them.
  Default: '86400' (24hours)

*-s*, *--split*=N::
  Download a file using N connections.
  If more than N URLs are given, first N URLs are used and remaining URLs are
  used for backup.
  If less than N URLs are given, those URLs are used more than once so that N
  connections total are made simultaneously.
  Please see *-j* option too.
  Please note that in Metalink download, this option has no effect and use
  *-C* option instead.
  Default: '5'

*-t*, *--timeout*=SEC::
  Set timeout in seconds.
  Default: '60'

*--uri-selector*=SELECTOR::
  Specify URI selection algorithm. The possible values are 'inorder',
  'feedback' and 'adaptive'.  If 'inorder' is given, URI is tried in
  the order appeared in the URI list.  If 'feedback' is given, aria2
  uses download speed observed in the previous downloads and choose
  fastest server in the URI list. This also effectively skips dead
  mirrors. The observed download speed is a part of performance
  profile of servers mentioned in *--server-stat-of* and
  *--server-stat-if* options.  If 'adaptive' is given, selects one of
  the best mirrors for the first and reserved connections.  For
  supplementary ones, it returns mirrors which has not been tested
  yet, and if each of them has already been tested, returns mirrors
  which has to be tested again. Otherwise, it doesn't select anymore
  mirrors. Like 'feedback', it uses a performance profile of servers.
  Default: 'feedback'

HTTP Specific Options
~~~~~~~~~~~~~~~~~~~~~
*--ca-certificate*=FILE::
  Use the certificate authorities in FILE to verify the peers.
  The certificate file must be in PEM format and can contain multiple CA
  certificates.
  Use *--check-certificate* option to enable verification.

*--certificate*=FILE::
  Use the client certificate in FILE.
  The certificate must be in PEM format.
  You may use *--private-key* option to specify the private key.

*--check-certificate*[='true'|'false']::
  Verify the peer using certificates specified in *--ca-certificate* option.
  Default: 'true'

*--http-auth-challenge*[='true'|'false']::
  Send HTTP authorization header only when it is requested by the
  server. If 'false' is set, then authorization header is always sent
  to the server.  There is an exception: if username and password are
  embedded in URI, authorization header is always sent to the server
  regardless of this option.  Default: 'false'

*--http-no-cache*[='true'|'false']::

   Send Cache-Control: no-cache and Pragma: no-cache header to avoid
   cached content.  If 'false' is given, these headers are not sent
   and you can add Cache-Control header with a directive you like
   using *--header* option. Default: 'true'

*--http-user*=USER::
  Set HTTP user. This affects all URLs.

*--http-passwd*=PASSWD::
  Set HTTP password. This affects all URLs.

*--http-proxy*=PROXY::

  Use this proxy server for HTTP.  To erase previously defined proxy,
  use "".  See also *--all-proxy* option.  This affects all URLs.  The
  format of PROXY is [\http://][USER:PASSWORD@]HOST[:PORT]

*--https-proxy*=PROXY::

  Use this proxy server for HTTPS. To erase previously defined proxy,
  use "". See also *--all-proxy* option.  This affects all URLs.  The
  format of PROXY is [\http://][USER:PASSWORD@]HOST[:PORT]

*--private-key*=FILE::
  Use the private key in FILE.
  The private key must be decrypted and in PEM format.
  The behavior when encrypted one is given is undefined.
  See also *--certificate* option.

*--referer*=REFERER::
  Set Referer. This affects all URLs.

*--enable-http-keep-alive*[='true'|'false']::
  Enable HTTP/1.1 persistent connection.
  Default: 'true'

*--enable-http-pipelining*[='true'|'false']::
  Enable HTTP/1.1 pipelining.
  Default: 'false'

*--header*=HEADER::
  Append HEADER to HTTP request header.
  You can use this option repeatedly to specify more than one header:
  aria2c *--header*="X-A: b78" *--header*="X-B: 9J1" "http://host/file"

*--load-cookies*=FILE::
  Load Cookies from FILE using the Firefox3 format (SQLite3) and the
  Mozilla/Firefox(1.x/2.x)/Netscape format.

[NOTE]
If aria2 is built without libsqlite3, then it doesn't support Firefox3 cookie format.

*--save-cookies*=FILE::

  Save Cookies to FILE in Mozilla/Firefox(1.x/2.x)/ Netscape
  format. If FILE already exists, it is overwritten. Session Cookies
  are also saved and their expiry values are treated as 0.  Possible
  Values: '/path/to/file'

*--use-head*[='true'|'false']::
  Use HEAD method for the first request to the HTTP server.
  Default: 'false'


*-U*, *--user-agent*=USER_AGENT::
  Set user agent for HTTP(S) downloads.
  Default: 'aria2/$VERSION', $VERSION is replaced by package version.

FTP Specific Options
~~~~~~~~~~~~~~~~~~~~
*--ftp-user*=USER::
  Set FTP user. This affects all URLs.
  Default: 'anonymous'

*--ftp-passwd*=PASSWD::
  Set FTP password. This affects all URLs.
  If user name is embedded but password is missing in URI, aria2 tries
  to resolve password using .netrc. If password is found in .netrc,
  then use it as password. If not, use the password specified in this
  option.
  Default: 'ARIA2USER@'

*-p*, *--ftp-pasv*[='true'|'false']::
  Use the passive mode in FTP.
  If 'false' is given, the active mode will be used.
  Default: 'true'

*--ftp-proxy*=PROXY::

  Use this proxy server for FTP.  To erase previously defined proxy,
  use "".  See also *--all-proxy* option.  This affects all URLs.  The
  format of PROXY is [\http://][USER:PASSWORD@]HOST[:PORT]

*--ftp-type*=TYPE::
  Set FTP transfer type. TYPE is either 'binary' or 'ascii'.
  Default: 'binary'

*--ftp-reuse-connection*[='true'|'false']::
  Reuse connection in FTP.
  Default: 'true'

BitTorrent/Metalink Options
~~~~~~~~~~~~~~~~~~~~~~~~~~~
*--select-file*=INDEX...::
  Set file to download by specifying its index.
  You can find the file index using the *--show-files* option.
  Multiple indexes can be specified by using ",", for example: '3,6'.
  You can also use "-" to specify a range: '1-5'.
  "," and "-" can be used together: '1-5,8,9'.
  When used with the -M option, index may vary depending on the query
  (see *--metalink-** options).

[NOTE]
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.

*-S*, *--show-files*::
  Print file listing of .torrent or .metalink file and exit.
  In case of .torrent file, additional information
  (infohash, piece length, etc) is also printed.

BitTorrent Specific Options
~~~~~~~~~~~~~~~~~~~~~~~~~~~

*--bt-enable-lpd*[='true'|'false']::

  Enable Local Peer Discovery.  If a private flag is set in a torrent,
  aria2 doesn't use this feature for that download even if 'true' is
  given.  Default: 'false'

*--bt-external-ip*=IPADDRESS::
  Specify the external IP address to report to a BitTorrent
  tracker. Although this function is named "external", it can accept
  any kind of IP addresses. IPADDRESS must be a numeric IP address.

*--bt-hash-check-seed*[='true'|'false']::
 If 'true' is given, after hash check using *--check-integrity* option and
 file is complete, continue to seed file. If you want to check file
 and download it only when it is damaged or incomplete, set this
 option to 'false'.  This option has effect only on BitTorrent download.
 Default: 'true'

*--bt-lpd-interface*=INTERFACE::

  Use given interface for Local Peer Discovery. If this option is not
  specified, the default interface is chosen. You can specify
  interface name and IP address.  Possible Values: interface, IP
  addres

*--bt-max-open-files*=NUM::
  Specify maximum number of files to open in each BitTorrent download.
  Default: '100'

*--bt-max-peers*=NUM::
  Specify the maximum number of peers per torrent.  '0' means
  unlimited.  See also *--bt-request-peer-speed-limit* option.
  Default: '55'

*--bt-metadata-only*[='true'|'false']::

  Download metadata only. The file(s) described in metadata will not
  be downloaded. This option has effect only when BitTorrent Magnet
  URI is used. See also *--bt-save-metadata* option.  Default: 'false'

*--bt-min-crypto-level*='plain'|'arc4'::
  Set minimum level of encryption method.
  If several encryption methods are provided by a peer, aria2 chooses the lowest
  one which satisfies the given level.
  Default: 'plain'

*--bt-prioritize-piece*='head'[=SIZE],'tail'[=SIZE]::

  Try to download first and last pieces of each file first. This is
  useful for previewing files. The argument can contain 2 keywords:
  'head' and 'tail'. To include both keywords, they must be separated
  by comma. These keywords can take one parameter, SIZE. For example,
  if 'head'=SIZE is specified, pieces in the range of first SIZE bytes
  of each file get higher priority.  'tail'=SIZE means the range of
  last SIZE bytes of each file. SIZE can include 'K' or 'M'(1K = 1024,
  1M = 1024K). If SIZE is omitted, SIZE=1M is used.

*--bt-require-crypto*='true'|'false'::
  If true is given, aria2 doesn't accept and establish connection with legacy
  BitTorrent handshake(\19BitTorrent protocol).
  Thus aria2 always uses Obfuscation handshake.
  Default: 'false' 

*--bt-request-peer-speed-limit*=SPEED::
  If the whole download speed of every torrent is lower than SPEED,
  aria2 temporarily increases the number of peers to try for more
  download speed. Configuring this option with your preferred download
  speed can increase your download speed in some cases.
  You can append 'K' or 'M'(1K = 1024, 1M = 1024K).
  Default: '50K'

*--bt-save-metadata*[='true'|'false']::

  Save metadata as .torrent file. This option has effect only when
  BitTorrent Magnet URI is used.  The filename is hex encoded info
  hash with suffix .torrent. The directory to be saved is the same
  directory where download file is saved. If the same file already
  exists, metadata is not saved. See also *--bt-metadata-only*
  option. Default: 'false'

*--bt-seed-unverified*[='true'|'false']::
  Seed previously downloaded files without verifying piece hashes.
  Default: 'false'

*--bt-stop-timeout*=SEC::

  Stop BitTorrent download if download speed is 0 in consecutive SEC
  seconds. If '0' is given, this feature is disabled.  Default: '0'

*--bt-tracker-interval*=SEC::
  Set the interval in seconds between tracker requests. This
  completely overrides interval value and aria2 just uses this value
  and ignores the min interval and interval value in the response of
  tracker. If '0' is set, aria2 determines interval based on the
  response of tracker and the download progress.  Default: '0'

*--dht-entry-point*=HOST:PORT::
  Set host and port as an entry point to DHT network.

*--dht-file-path*=PATH::
  Change the DHT routing table file to PATH.
  Default: '$HOME/.aria2/dht.dat'

*--dht-listen-port*=PORT...::
  Set UDP listening port for DHT.
  Multiple ports can be specified by using ",", for example: '6881,6885'.
  You can also use "-" to specify a range: '6881-6999'. "," and "-" can be used
  together.
  Default: '6881-6999'

[NOTE]
Make sure that the specified ports are open for incoming UDP traffic.

*--enable-dht*[='true'|'false']::
  Enable DHT functionality. If a private flag is set in a torrent, aria2
  doesn't use DHT for that download even if 'true' is given.
  Default: 'true'

*--enable-peer-exchange*[='true'|'false']::
  Enable Peer Exchange extension. If a private flag is set in a torrent, this
  feature is disabled for that download even if 'true' is given.
  Default: 'true'

*--follow-torrent*='true'|'false'|'mem'::
  If 'true' or 'mem' 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 'mem' is specified, a torrent file is not written to the disk, but is just
  kept in memory.
  If 'false' is specified, the action mentioned above is not taken.
  Default: 'true'

*-O*, *--index-out*=INDEX=PATH::
  Set file path for file with index=INDEX. You can find the file index
  using the *--show-files* option.  PATH is a relative path to the
  path specified in *--dir* option. You can use this option multiple
  times. Using this option, you can specify the output filenames of
  BitTorrent downloads.

*--listen-port*=PORT...::
  Set TCP port number for BitTorrent downloads.
  Multiple ports can be specified by using ",",  for example: '6881,6885'.
  You can also use "-" to specify a range: '6881-6999'.
  "," and "-" can be used together: '6881-6889,6999'.
  Default: '6881-6999'

[NOTE]
Make sure that the specified ports are open for incoming TCP traffic.

*--max-overall-upload-limit*=SPEED::
  Set max overall upload speed in bytes/sec.
  '0' means unrestricted.
  You can append 'K' or 'M'(1K = 1024, 1M = 1024K).
  To limit the upload speed per torrent, use *--max-upload-limit* option.
  Default: '0'

*-u*, *--max-upload-limit*=SPEED::
  Set max upload speed per each torrent in bytes/sec.
  '0' means unrestricted.
  You can append 'K' or 'M'(1K = 1024, 1M = 1024K).
  To limit the overall upload speed, use *--max-overall-upload-limit* option.
  Default: '0'

*--peer-id-prefix*=PEER_ID_PREFIX::

  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, random
  byte data are added to make its length 20 bytes.
  Default: 'aria2/$VERSION-', $VERSION is replaced by package version.

*--seed-ratio*=RATIO::
  Specify share ratio. Seed completed torrents until share ratio reaches
  RATIO.
  You are strongly encouraged to specify equals or more than '1.0' here.
  Specify '0.0' 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: '1.0'

*--seed-time*=MINUTES::
  Specify seeding time in minutes. Also see the *--seed-ratio* option.

*-T*, *--torrent-file*=TORRENT_FILE::

  The path to the .torrent file.  You are not required to use this
  option because you can specify .torrent files without *-T*.

Metalink Specific Options
~~~~~~~~~~~~~~~~~~~~~~~~~
*--follow-metalink*='true'|'false'|'mem'::
  If 'true' or 'mem' is specified, when a file whose suffix is ".metalink" or content
  type of "application/metalink+xml" is downloaded, aria2 parses it as a metalink
  file and downloads files mentioned in it.
  If 'mem' is specified, a metalink file is not written to the disk, but is just
  kept in memory.
  If 'false' is specified, the action mentioned above is not taken.
  Default: 'true'

*-M*, *--metalink-file*=METALINK_FILE::

  The file path to .metalink file. Reads input from stdin when '-' is
  specified.  You are not required to use this option because you can
  specify .metalink files without *-M*.

*-C*, *--metalink-servers*=NUM_SERVERS::
  The number of servers to connect to simultaneously.
  Some Metalinks regulate the number of servers to connect.
  aria2 strictly respects them.
  This means that if Metalink defines the maxconnections attribute lower
  than NUM_SERVERS, then aria2 uses the value of maxconnections attribute
  instead of NUM_SERVERS.
  See also *-s* and *-j* options.
  Default: '5'

*--metalink-language*=LANGUAGE::
  The language of the file to download.

*--metalink-location*=LOCATION[,...]::
  The location of the preferred server.
  A comma-delimited list of locations is acceptable, for example, 'jp,us'.

*--metalink-os*=OS::
  The operating system of the file to download.

*--metalink-version*=VERSION::
  The version of the file to download.

*--metalink-preferred-protocol*=PROTO::
  Specify preferred protocol.
  The possible values are 'http', 'https', 'ftp' and 'none'.
  Specify 'none' to disable this feature.
  Default: 'none'
 
*--metalink-enable-unique-protocol*='true'|'false'::
  If 'true' 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: 'true'

XML-RPC Options
~~~~~~~~~~~~~~~

*--enable-xml-rpc*[='true'|'false']::
  Enable XML-RPC server.  It is strongly recommended to set username
  and password using *--xml-rpc-user* and *--xml-rpc-passwd*
  option. See also *--xml-rpc-listen-port* option.  Default: 'false'

*--xml-rpc-listen-all*[='true'|'false']::

  Listen incoming XML-RPC requests on all network interfaces. If false
  is given, listen only on local loopback interface.  Default: 'false'

*--xml-rpc-listen-port*=PORT::
  Specify a port number for XML-RPC server to listen to.  Possible
  Values: '1024'-'65535' Default: '6800'

*--xml-rpc-max-request-size*=SIZE::

  Set max size of XML-RPC request. If aria2 detects the request is
  more than SIZE bytes, it drops connection. Default: '2M'

*--xml-rpc-passwd*=PASSWD::
  Set XML-RPC password.

*--xml-rpc-user*=USER::
  Set XML-RPC user.

Advanced Options
~~~~~~~~~~~~~~~~
*--allow-overwrite*='true'|'false'::

  Restart download from scratch if the corresponding control file
  doesn't exist.  See also *--auto-file-renaming* option.  Default:
  'false'

*--allow-piece-length-change*='true'|'false'::
  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: 'false'

*--async-dns*[='true'|'false']::
  Enable asynchronous DNS.
  Default: 'true'

*--auto-file-renaming*[='true'|'false']::
  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: 'true'

*--auto-save-interval*=SEC::
  Save a control file(*.aria2) every SEC seconds.
  If '0' is given, a control file is not saved during download. aria2 saves a
  control file when it stops regardless of the value.
  The possible values are between '0' to '600'.
  Default: '60'

*--conf-path*=PATH::
  Change the configuration file path to PATH.
  Default: '$HOME/.aria2/aria2.conf'

*-D*, *--daemon*::
  Run as daemon. The current working directory will be changed to '/'
  and standard input, standard output and standard error will be
  redirected to '/dev/null'. Default: 'false'

*--disable-ipv6*[='true'|'false']::

  Disable IPv6. This is useful if you have to use broken DNS and want
  to avoid terribly slow AAAA record lookup. Default: 'false'

*--enable-direct-io*[='true'|'false']::
  Enable directI/O, which lowers cpu usage while allocating/checking files.
  Turn off if you encounter any error.
  Default: 'true'

*--event-poll*=POLL::
  Specify the method for polling events.  The possible Values are
  'epoll' and 'select'. If you use recent Linux that has epoll, then
  the default value is 'epoll'.  Otherwise, the default value is
  'select'.

*--file-allocation*=METHOD::

  Specify file allocation method.
  'none' doesn't pre-allocate file space. 'prealloc' pre-allocates file space
  before download begins. This may take some time depending on the size of the
  file.
  If you are using newer file systems such as ext4
  (with extents support), btrfs or xfs, 'falloc' is
  your best choice. It allocates large(few GiB)
  files almost instantly. Don't use 'falloc' with
  legacy file systems such as ext3 because it takes
  almost same time as 'prealloc' and it blocks aria2
  entirely until allocation finishes. 'falloc' may
  not be available if your system doesn't have
  *posix_fallocate*() function.
  Possible Values: 'none', 'prealloc', 'falloc'
  Default: 'prealloc'

*--human-readable*[='true'|'false']::

  Print sizes and speed in human readable format (e.g., 1.2Ki, 3.4Mi)
  in the console readout. Default: 'true'

*--interface*=INTERFACE::

  Bind sockets to given interface. You can specify interface name, IP
  address and hostname.
  Possible Values: interface, IP address, hostname

[NOTE]
If an interface has multiple addresses, it is highly recommended to
specify IP address explicitly. See also *--disable-ipv6*.  If your
system doesn't have getifaddrs(), this option doesn't accept interface
name.

*--log-level*=LEVEL::
  Set log level to output.
  LEVEL is either 'debug', 'info', 'notice', 'warn' or 'error'.
  Default: 'debug'

*--on-download-complete*=COMMAND::

  Set the command to be executed when download completes.  See
  *--on-download-start* option for the requirement of COMMAND.  See
  also *--on-download-stop* option.  Possible Values:
  '/path/to/command'

*--on-download-error*=COMMAND::

  Set the command to be executed when download aborts due to error.
  See *--on-download-start* option for the requirement of COMMAND.
  See also *--on-download-stop* option.  Possible Values:
  '/path/to/command'

*--on-download-start*=COMMAND::

  Set the command to be executed when download starts up. COMMAND must
  take just one argument and GID is passed to COMMAND as a first
  argument.  Possible Values: '/path/to/command'

*--on-download-stop*=COMMAND::

  Set the command to be executed when download stops. You can override
  the command to be executed for particular download result using
  *--on-download-complete* and *--on-download-error*. If they are
  specified, command specified in this option is not executed.  See
  *--on-download-start* option for the requirement of COMMAND.
  Possible Values: '/path/to/command'

*--summary-interval*=SEC::
  Set interval in seconds to output download progress summary.
  Setting '0' suppresses the output.
  Default: '60'

[NOTE]
In multi file torrent downloads, the files adjacent forward to the specified files
are also allocated if they share the same piece.

*-Z*, *--force-sequential*[='true'|'false']::
  Fetch URIs in the command-line sequentially and download each URI in a
  separate session, like the usual command-line download utilities.
  Default: 'false'

*--max-overall-download-limit*=SPEED::
  Set max overall download speed in bytes/sec.  '0' means
  unrestricted.  You can append 'K' or 'M'(1K = 1024, 1M = 1024K).  To
  limit the download speed per download, use *--max-download-limit*
  option.  Default: '0'

*--max-download-limit*=SPEED::
  Set max download speed per each download in bytes/sec. '0' means
  unrestricted.  You can append 'K' or 'M'(1K = 1024, 1M = 1024K).  To
  limit the overall download speed, use *--max-overall-download-limit*
  option.  Default: '0'

*--no-conf*::
  Disable loading aria2.conf file.

*--no-file-allocation-limit*=SIZE::
  No file allocation is made for files whose size is smaller than SIZE.
  You can append 'K' or 'M'(1K = 1024, 1M = 1024K).
  Default: '5M'

*-P*, *--parameterized-uri*[='true'|'false']::
  Enable parameterized URI support.
  You can specify set of parts: 'http://{sv1,sv2,sv3}/foo.iso'.
  Also you can specify numeric sequences with step counter:
  '\http://host/image[000-100:2].img'.
  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: 'false'

*-q*, *--quiet*[='true'|'false']::
  Make aria2 quiet (no console output).
  Default: 'false'

*--realtime-chunk-checksum*='true'|'false'::
   Validate chunk of data by calculating checksum while downloading a file if
   chunk checksums are provided.
   Default: 'true'

*--stop*=SEC::
  Stop application after SEC seconds has passed.
  If '0' is given, this feature is disabled.
  Default: '0'
 
*-v*, *--version*::
  Print the version number, copyright and the configuration information and
  exit.

Options That Take An Optional Argument
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The options that have its argument surrounded by square brackets([])
take an optional argument. Usually omiting the argument is evaluated to 'true'.
If you use short form of these options(such as '-V') and give
an argument, then the option name and its argument should be concatenated(e.g.
'-Vfalse'). If any spaces are inserted between the option name and the argument,
the argument will be treated as URI and usually this is not what you expect.

URI, MAGNET, TORRENT_FILE, METALINK_FILE
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

You can specify multiple URLs in command-line.  Unless you specify
*-Z* option, all URLs must point to the same file or downloading will
fail.

You can specify arbitrary number of BitTorrent Magnet URI. Please note
that they are always treated as a separate download.  Both hex encoded
40 characters Info Hash and Base32 encoded 32 characters Info Hash are
supported. The multiple "tr" parameters are supported.  Because
BitTorrent Magnet URI is likely to contain "&" character, it is highly
recommended to always quote URI with single(') or double(") quotation.
It is strongly recommended to enable DHT especially when "tr"
parameter is missing. See http://www.bittorrent.org/beps/bep_0009.html
for more details about BitTorrent Magnet URI.

You can also specify arbitrary number of torrent files and metalink files
stored on a local drive. Please note that they are always treated as a
separate download.

You can specify both torrent file with -T option and URLs. By doing
this, you can 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.  For single file torrents, URL can be a complete
URL pointing to the resource or if URL ends with /, name in torrent
file in torrent is added. For multi-file torrents, name and path are
added to form a URL for each file.

[NOTE]
Make sure that URL is quoted with single(') or double(") quotation if it
contains "&" or any characters that have special meaning in shell.

Resuming Download
~~~~~~~~~~~~~~~~~

Usually, you can resume transfer by just issuing same command(aria2c
URL) if the previous transfer is made by aria2.

If the previous transfer is made by a browser or wget like sequential
download manager, then use -c option to continue the transfer(aria2c
*-c* URL).


EXIT STATUS
-----------

Because aria2 can handle multiple downloads at once, it encounters
lots of errors in a session.  aria2 returns the following exit status
based on the last error encountered.

*0*::
  If all downloads are successful.

*1*::
  If an unknown error occurs.

*2*::
  If time out occurs.

*3*::
  If a resource is not found.

*4*::
  If aria2 sees the specfied number of "resource not found" error.
  See *--max-file-not-found* option).

*5*::
  If a download aborts because download speed is too slow.
  See *--lowest-speed-limit* option)

*6*::
  If network problem occurs.

*7*::
  If there are unfinished downloads. This error is only reported if
  all finished downloads are successful and there are unfinished
  downloads in a queue when aria2 exits by pressing Ctrl-C by an user
  or sending TERM or INT signal.

[NOTE]
An error occurred in a finished download will not be reported
as exit status.

ENVIRONMENT
-----------
aria2 recognizes the following environment variables.

http_proxy [\http://][USER:PASSWORD@]HOST[:PORT]::
  Specify proxy server for use in HTTP.
  Overrides http-proxy value in configuration file.
  The command-line option *--http-proxy* overrides this value.

https_proxy [\http://][USER:PASSWORD@]HOST[:PORT]::
  Specify proxy server for use in HTTPS.
  Overrides https-proxy value in configuration file.
  The command-line option *--https-proxy* overrides this value.

ftp_proxy [\http://][USER:PASSWORD@]HOST[:PORT]::
  Specify proxy server for use in FTP.
  Overrides ftp-proxy value in configuration file.
  The command-line option *--ftp-proxy* overrides this value.

all_proxy [\http://][USER:PASSWORD@]HOST[:PORT]::
  Specify proxy server for use if no protocol-specific proxy is specified.
  Overrides all-proxy value in configuration file.
  The command-line option *--all-proxy* overrides this value.

no_proxy [DOMAIN,...]::
  Specify comma-separated hostname or domains to which proxy should not be used.
  Overrides no-proxy value in configuration file.
  The command-line option *--no-proxy* overrides this value.

FILES
-----
aria2.conf
~~~~~~~~~~

By default, aria2 parses '$HOME/.aria2/aria2.conf' as a configuraiton
file. You can specify the path to configuration file using
*--conf-path* option.  If you don't want to use the configuraitonf
file, use *--no-conf* option.

The configuration file is a text file and has 1 option per each
line. In each line, you can specify name-value pair in the format:
NAME=VALUE, where name is the long command-line option name without
"--" prefix. You can use same syntax for the command-line option. The
lines beginning "#" are treated as comments.

--------------------------------------
# sample configuration file for aria2c
listen-port=60000
dht-listen-port=60000
seed-ratio=1.0
max-upload-limit=50K
ftp-pasv=true
--------------------------------------

dht.dat
~~~~~~~~
By default, the routing table of DHT is saved to the path $HOME/.aria2/dht.dat.

Control File
~~~~~~~~~~~~

aria2 uses a control file to track the progress of a download.  A
control file is placed in the same directory as the downloading 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 -V option
to aria2c in command-line.

Input File
~~~~~~~~~~

The input file can contain a list of URIs for aria2 to download.  You
can specify multiple URIs for a single entity: separate URIs on a
single line using the TAB character.

Each line is treated as if it is provided in command-line argument.
Therefore they are affected by *-Z* and *-P* options.

Additionally, the following options can be specified after each line
of URIs. These optional lines must start with white space(s).

* dir
* check-integrity
* continue
* all-proxy
* connect-timeout
* dry-run
* lowest-speed-limit
* max-file-not-found
* max-tries
* no-proxy
* out
* proxy-method
* remote-time
* split
* timeout
* http-auth-challenge
* http-no-cache
* http-user
* http-passwd
* http-proxy
* https-proxy
* referer
* enable-http-keep-alive
* enable-http-pipelining
* header
* use-head
* user-agent
* ftp-user
* ftp-passwd
* ftp-pasv
* ftp-proxy
* ftp-type
* ftp-reuse-connection
* no-netrc
* select-file
* bt-external-ip
* bt-hash-check-seed
* bt-max-open-files
* bt-max-peers
* bt-metadata-only
* bt-min-crypto-level
* bt-prioritize-piece
* bt-require-crypto
* bt-request-peer-speed-limit
* bt-save-metadata
* bt-seed-unverified
* bt-stop-timeout
* bt-tracker-interval
* enable-peer-exchange
* follow-torrent
* index-out
* max-upload-limit
* seed-ratio
* seed-time
* follow-metalink
* metalink-servers
* metalink-language
* metalink-location
* metalink-os
* metalink-version
* metalink-preferred-protocol
* metalink-enable-unique-protocol
* allow-overwrite
* allow-piece-length-change
* async-dns
* auto-file-renaming
* file-allocation
* max-download-limit
* no-file-allocation-limit
* parameterized-uri
* realtime-chunk-checksum

These options have exactly same meaning of the ones in the
command-line options, but it just applies to the URIs it belongs to.

For example, the content of uri.txt is

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
http://server/file.iso http://mirror/file.iso
  dir=/iso_images
  out=file.img
http://foo/bar
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

If aria2 is executed with *-i* uri.txt *-d* /tmp options, then
'file.iso' is saved as '/iso_images/file.img' and it is downloaded
from \http://server/file.iso and \http://mirror/file.iso.  The file
'bar' is downloaded from \http://foo/bar and saved as '/tmp/bar'.

In some cases, *out* parameter has no effect.  See note of *--out*
option for the restrictions.

Server Performance Profile
~~~~~~~~~~~~~~~~~~~~~~~~~~

This section describes the format of server performance profile.  The
file is plain text and each line has several NAME=VALUE pair,
delimited by comma.  Currently following NAMEs are recognized:

host::
  Hostname of the server. Required.

protocol::
  Protocol for this profile, such as ftp, http. Required.

dl_speed::
  The average download speed observed in the previous download in
  bytes per sec.  Required.

sc_avg_speed::
  The average download speed observed in the previous download in
  bytes per sec. This value is only updated if the download is done in
  single connection environment and only used by
  AdaptiveURISelector. Optional.

mc_avg_speed::
  The average download speed observed in the previous download in
  bytes per sec. This value is only updated if the download is done in
  multi connection environment and only used by
  AdaptiveURISelector. Optional.

counter::
  How many times the server is used. Currently this value is only used
  by AdaptiveURISelector.  Optional.

last_updated::
  Last contact time in GMT with this server, specified in the seconds
  since the Epoch(00:00:00 on January 1, 1970, UTC). Required.

status::
  ERROR is set when server cannot be reached or out-of-service or
  timeout occurred. Otherwise, OK is set.

Those fields must exist in one line. The order of the fields is not
significant. You can put pairs other than the above; they are simply
ignored.

An example follows:
--------------------------------------------------------------------------------
host=localhost, protocol=http, dl_speed=32000, last_updated=1222491640, status=OK
host=localhost, protocol=ftp, dl_speed=0, last_updated=1222491632, status=ERROR
--------------------------------------------------------------------------------

XML-RPC INTERFACE
-----------------

Terminology
~~~~~~~~~~~

GID::

  GID(or gid) is the key to manage each download. Each download has an
  unique GID. Currently GID looks like an integer, but don't treat it
  as integer because it may be changed to another type in the future
  release. Please note that GID is session local and not persisted
  when aria2 exits.

Methods
~~~~~~~

*aria2.addUri* 'uris[, options[, position]]'

This method adds new HTTP(S)/FTP/BitTorrent Magnet URI.  'uris' is of
type array and its element is URI which is of type string.  For
BitTorrent Magnet URI, 'uris' must have only one element and it should
be BitTorrent Magnet URI.  'options' is of type struct and its members
are a pair of option name and value. See *Options* below for more
details.  If 'position' is given as an integer starting from 0, the
new download is inserted at 'position' in the waiting queue. If
'position' is not given or 'position' is larger than the size of the
queue, it is appended at the end of the queue.  This method returns
GID of registered download.

*aria2.addTorrent* 'torrent[, uris[, options[, position]]]'

This method adds BitTorrent download by uploading .torrent file.  If
you want to add BitTorrent Magnet URI, use *aria2.addUri* method
instead.  'torrent' is of type base64 which contains Base64-encoded
.torrent file.  'uris' is of type array and its element is URI which
is of type string. 'uris' is used for Web-seeding.  For single file
torrents, URI can be a complete URI pointing to the resource or if URI
ends with /, name in torrent file is added. For multi-file torrents,
name and path in torrent are added to form a URI for each file.
'options' is of type struct and its members are a pair of option name
and value. See *Options* below for more details.  If 'position' is
given as an integer starting from 0, the new download is inserted at
'position' in the waiting queue. If 'position' is not given or
'position' is larger than the size of the queue, it is appended at the
end of the queue.  This method returns GID of registered download.

*aria2.addMetalink* 'metalink[, options[, position]]'

This method adds Metalink download by uploading .metalink file.
'metalink' is of type base64 which contains Base64-encoded .metalink
file.  'options' is of type struct and its members are a pair of
option name and value. See *Options* below for more details.  If
'position' is given as an integer starting from 0, the new download is
inserted at 'position' in the waiting queue. If 'position' is not
given or 'position' is larger than the size of the queue, it is
appended at the end of the queue.  This method returns array of GID of
registered download.

*aria2.remove* 'gid'

This method removes the download denoted by 'gid'. 'gid' is of type
string. If specified download is in progress, it is stopped at
first. The status of removed download becomes "removed".  This method
returns GID of removed download.

*aria2.forceRemove* 'gid'

This method removes the download denoted by 'gid'.  This method
behaves just like *aria2.remove* except that this method removes
download without any action which takes time such as contacting
BitTorrent tracker.

*aria2.tellStatus* 'gid'

This method returns download progress of the download denoted by
'gid'. 'gid' is of type string. The response is of type struct and it
contains following keys. The value type is string.

gid::

  GID of this download.

status::

  "active" for currently downloading/seeding entry. "waiting" for the
  entry in the queue; download is not started. "error" for the stopped
  download because of error. "complete" for the stopped and completed
  download. "removed" for the download removed by user.

totalLength::

  Total length of this download in bytes.

completedLength::

  Completed length of this download in bytes.

uploadLength::

  Uploaded length of this download in bytes.

bitfield::

  Hexadecimal representation of the download progress. The highest bit
  corresponds to piece index 0. The set bits indicate the piece is
  available and unset bits indicate the piece is missing. The spare
  bits at the end are set to zero.

downloadSpeed::

  Download speed of this download measured in bytes/sec.

uploadSpeed::

  Upload speed of this download measured in bytes/sec.

infoHash::

  InfoHash. BitTorrent only.

numSeeders::

  The number of seeders the client has connected to. BitTorrent only.

pieceLength::

  Piece length in bytes.

numPieces::

  The number of pieces.

connections::

  The number of peers/servers the client has connected to.

errorCode::

  The last error code occurred in this download. The value is of type
  string. The error codes are defined in EXIT STATUS section. This
  value is only available for stopped/completed downloads.

followedBy::

  List of GIDs which are generated by the consequence of this
  download. For example, when aria2 downloaded Metalink file, it
  generates downloads described in it(see *--follow-metalink*
  option). This value is useful to track these auto generated
  downloads. If there is no such downloads, this key will not
  be included in the response.

belongsTo::

  GID of a parent download. Some downloads are a part of another
  download.  For example, if a file in Metalink has BitTorrent
  resource, the download of .torrent is a part of that file.  If this
  download has no parent, this key will not be included in the
  response.

dir::

  Directory to save files. This key is not available for stopped
  downloads.

files::

  Returns the list of files. The element of list is the same struct
  used in *aria2.getFiles* method.


bittorrent::

  Struct which contains information retrieved from .torrent
  file. BitTorrent only. It contains following keys.

  announceList;;

    List of lists of announce URI. If .torrent file contains announce
    and no announce-list, announce is converted to announce-list
    format.

  comment;;

    The comment for the torrent. comment.utf-8 is used if available.

  creationDate;;

    The creation time of the torrent. The value is an integer since
    the Epoch, measured in seconds.

  mode;;

    File mode of the torrent. The value is either 'single' or 'multi'.

  info;;

    Struct which contains data from Info dictionary. It contains
    following keys.

    name:::

      name in info dictionary. name.utf-8 is used if available.

*aria2.getUris* 'gid'

This method returns URIs used in the download denoted by 'gid'.  'gid'
is of type string. The response is of type array and its element is of
type struct and it contains following keys. The value type is string.

uri::

  URI

status::

  'used' if the URI is already used. 'waiting' if the URI is waiting
  in the queue.

*aria2.getFiles* 'gid'

This method returns file list of the download denoted by 'gid'. 'gid'
is of type string. The response is of type array and its element is of
type struct and it contains following keys. The value type is string.

index::

  Index of file. Starting with 1. This is the same order with the
  files in multi-file torrent.

path::

  File path.

length::

  File size in bytes.

selected::

  "true" if this file is selected by *--select-file* option. If
  *--select-file* is not specified or this is single torrent or no
  torrent download, this value is always "true". Otherwise "false".

uris::

  Returns the list of URI for this file. The element of list is the
  same struct used in *aria2.getUris* method.

*aria2.getPeers* 'gid'

This method returns peer list of the download denoted by 'gid'. 'gid'
is of type string. This method is for BitTorrent only.  The response
is of type array and its element is of type struct and it contains
following keys. The value type is string.

peerId::

  Percent-encoded peer ID.

ip::

  IP address of the peer.

port::

  Port number of the peer.

bitfield::

  Hexadecimal representation of the download progress of the peer. The
  highest bit corresponds to piece index 0. The set bits indicate the
  piece is available and unset bits indicate the piece is missing. The
  spare bits at the end are set to zero.

amChoking::

  "true" if this client is choking the peer. Otherwise "false".

peerChoking::

  "true" if the peer is choking this client. Otherwise "false".

downloadSpeed::

  Download speed (byte/sec) that this client obtains from the peer.

uploadSpeed::

  Upload speed(byte/sec) that this client uploads to the peer. 

seeder::

  "true" is this client is a seeder. Otherwise "false".

*aria2.getServers* 'gid'

This method returns currently connected HTTP(S)/FTP servers of the download denoted by 'gid'. 'gid' is of type string. The response
is of type array and its element is of type struct and it contains
following keys. The value type is string.

index::

  Index of file. Starting with 1. This is the same order with the
  files in multi-file torrent.

servers::

  The list of struct which contains following keys.

  uri;;

    URI originally added.

  currentUri;;

    This is the URI currently used for downloading. If redirection is
    involved, currentUri and uri may differ.

  downloadSpeed;;

    Download speed (byte/sec)

*aria2.tellActive*

This method returns the list of active downloads.  The response is of
type array and its element is the same struct returned by
*aria2.tellStatus* method.

*aria2.tellWaiting* 'offset, num'

This method returns the list of waiting download.  'offset' is of type
integer and specifies the offset from the download waiting at the
front. 'num' is of type integer and specifies the number of downloads
to be returned.

If offset is a positive integer, this method returns downloads in the
range of ['offset', 'offset'+'num').

'offset' can be a negative integer. 'offset' == -1 points last
download in the waiting queue and 'offset' == -2 points the download
before the last download, and so on. The downloads in the response are
in reversed order.

For example, imagine that three downloads "A","B" and "C" are waiting
in this order. aria2.tellWaiting(0, 1) returns
["A"]. aria2.tellWaiting(1, 2) returns ["B", "C"].
aria2.tellWaiting(-1, 2) returns ["C", "B"].

The response is of type array and its element is the same struct
returned by *aria2.tellStatus* method.

*aria2.tellStopped* 'offset, num'

This method returns the list of stopped download.  'offset' is of type
integer and specifies the offset from the oldest download. 'num' is of
type integer and specifies the number of downloads to be returned.

'offset' and 'num' have the same semantics as *aria2.tellWaiting*
method.

The response is of type array and its element is the same struct
returned by *aria2.tellStatus* method.

*aria2.changePosition* 'gid, pos, how'

This method changes the position of the download denoted by
'gid'. 'pos' is of type integer. 'how' is of type string. If 'how' is
"POS_SET", it moves the download to a position relative to the
beginning of the queue.  If 'how' is "POS_CUR", it moves the download
to a position relative to the current position. If 'how' is "POS_END",
it moves the download to a position relative to the end of the
queue. If the destination position is less than 0 or beyond the end of
the queue, it moves the download to the beginning or the end of the
queue respectively. The response is of type integer and it is the
destination position.

For example, if GID#1 is placed in position 3, aria2.changePosition(1,
-1, POS_CUR) will change its position to 2. Additional
aria2.changePosition(1, 0, POS_SET) will change its position to 0(the
beginning of the queue).

*aria2.changeUri* 'gid, fileIndex, delUris, addUris[, position]'

This method removes URIs in 'delUris' from and appends URIs in
'addUris' to download denoted by 'gid'. 'delUris' and 'addUris' are
list of string. A download can contain multiple files and URIs are
attached to each file.  'fileIndex' is used to select which file to
remove/attach given URIs. 'fileIndex' is 1-based. 'position' is used
to specify where URIs are inserted in the existing waiting URI
list. 'position' is 0-based. When 'position' is omitted, URIs are
appended to the back of the list.  This method first execute removal
and then addition. 'position' is the position after URIs are removed,
not the position when this method is called.  When removing URI, if
same URIs exist in download, only one of them is removed for each URI
in 'delUris'. In other words, there are three URIs
"http://example.org/aria2" and you want remove them all, you have to
specify (at least) 3 "http://example.org/aria2" in 'delUris'.  This
method returns a list which contains 2 integers. The first integer is
the number of URIs deleted. The second integer is the number of URIs
added.

*aria2.getOption* 'gid'

This method returns options of the download denoted by 'gid'.  The
response is of type struct. Its key is the name of option.  The value type
is string.

*aria2.changeOption* 'gid, options'

This method changes options of the download denoted by 'gid'
dynamically.  'gid' is of type string.  'options' is of type struct
and the available options are: *bt-max-peers*,
*bt-request-peer-speed-limit*, *max-download-limit* and
*max-upload-limit*.  This method returns "OK" for success.

*aria2.getGlobalOption*

This method returns global options.  The response is of type
struct. Its key is the name of option.  The value type is string.
Because global options are used as a template for the options of newly
added download, the response contains keys returned by
*aria2.getOption* method.

*aria2.changeGlobalOption* 'options'

This method changes global options dynamically.  'options' is of type
struct and the available options are *max-concurrent-downloads*,
*max-overall-download-limit* and *max-overall-upload-limit*.  This
method returns "OK" for success.

*aria2.purgeDownloadResult*

This method purges completed/error/removed downloads to free memory.
This method returns "OK".

*aria2.getVersion*

This method returns version of the program and the list of enabled
features. The response is of type struct and contains following keys.

version::

  Version number of the program in string.

enabledFeatures::

  List of enabled features. Each feature name is of type string.

*aria2.getSessionInfo*

This method returns session information.
The response is of type struct and contains following key.

sessionId::

  Session ID, which is generated each time when aria2 is invoked.

*system.multicall* 'methods'

This methods encapsulates multiple method calls in a single request.
'methods' is of type array and its element is struct.  The struct
contains two keys: "methodName" and "params".  "methodName" is the
method name to call and "params" is array containing parameters to the
method.  This method returns array of responses.  The element of array
will either be a one-item array containing the return value of each
method call or struct of fault element if an encapsulated method call
fails.

Error Handling
~~~~~~~~~~~~~~

In case of error, aria2 returns faultCode=1 and the error message in
faultString.

Options
~~~~~~~

Same options for *-i* list are available. See *Input File* subsection
for complete list of options.

In the option struct, name element is option name(without preceding
"--") and value element is argument as string.

-------------------------------------------------
<struct>
  <member>
    <name>split</name>
    <value><string>1</string></value>
  </member>
  <member>
    <name>http-proxy</name>
    <value><string>http://proxy/</string></value>
  </member>
</struct>
-------------------------------------------------

*header* and *index-out* option are allowed multiple times in
command-line. Since name should be unique in struct(many XML-RPC
library implementation uses hash or dict for struct), single string is
not enough. To overcome this situation, they can take array as value
as well as string.

---------------------------------------------------------------
<struct>
  <member>
    <name>header</name>
    <value>
      <array>
        <data>
          <value><string>Accept-Language: ja</string></value>
          <value><string>Accept-Charset: utf-8</string></value>
        </data>
      </array>
    </value>
  </member>
</struct>
---------------------------------------------------------------

Sample XML-RPC Client Code
~~~~~~~~~~~~~~~~~~~~~~~~~~

The following Ruby script adds 'http://localhost/aria2.tar.bz2' to
aria2c operated on localhost with option *--dir*='/downloads' and
prints its reponse.

----------------------------------------------
#!/usr/bin/env ruby

require 'xmlrpc/client'
require 'pp'

client=XMLRPC::Client.new2("http://localhost:6800/rpc")

options={ "dir" => "/downloads" }
result=client.call("aria2.addUri", [ "http://localhost/aria2.tar.bz2" ], options)

pp result
----------------------------------------------

If you are a Python lover, you can use xmlrpclib(for Python3.x, use
xmlrpc.client instead) to interact with aria2.

----------------------------------------------
import xmlrpclib
from pprint import pprint

s = xmlrpclib.ServerProxy("http://localhost:6800/rpc")
r = s.aria2.addUri(["http://localhost/aria2.tar.bz2"], {"dir":"/downloads"})
pprint(r)
----------------------------------------------

EXAMPLE
-------

HTTP/FTP Segmented Download
~~~~~~~~~~~~~~~~~~~~~~~~~~~
Download a file
^^^^^^^^^^^^^^^
--------------------------------
aria2c "http://host/file.zip"
--------------------------------
[NOTE]
aria2 uses 5 connections to download 1 file by default.

Download a file using 1 connection
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
----------------------------------
aria2c -s1 "http://host/file.zip"
----------------------------------
[NOTE]
aria2 uses 5 connections to download 1 file by default.
-s1 limits the number of connections to just 1.

[NOTE]
To pause a download, press Ctrl-C. You can resume the transfer by running aria2c with the same argument in the same directory. You can change URLs as long as they are pointing to the same file.

Download a file from 2 different HTTP servers
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
------------------------------------------------------
aria2c "http://host/file.zip" "http://mirror/file.zip"
------------------------------------------------------

Download a file from HTTP and FTP servers
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-----------------------------------------------------
aria2c "http://host1/file.zip" "ftp://host2/file.zip"
-----------------------------------------------------

Download files listed in a text file concurrently
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
------------------------
aria2c -ifiles.txt -j2
------------------------
[NOTE]
-j option specifies the number of parallel downloads.

Using proxy
^^^^^^^^^^^
For HTTP:
----------------------------------------------------------
aria2c --http-proxy="http://proxy:8080" "http://host/file"
----------------------------------------------------------
For FTP:
--------------------------------------------------------
aria2c --ftp-proxy="http://proxy:8080" "ftp://host/file"
--------------------------------------------------------

[NOTE]
See *--http-proxy*, *--https-proxy*, *--ftp-proxy* and *--all-proxy* for
details.
You can specify proxy in the environment variables. See *ENVIRONMENT* section.

Proxy with authorization
^^^^^^^^^^^^^^^^^^^^^^^^
----------------------------------------------------------------------------
aria2c --http-proxy="http://username:password@proxy:8080" "http://host/file"
----------------------------------------------------------------------------

Metalink Download
~~~~~~~~~~~~~~~~~
Download files with remote Metalink
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
--------------------------------------------------------
aria2c --follow-metalink=mem "http://host/file.metalink"
--------------------------------------------------------

Download using a local metalink file
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
----------------------------------------------------------
aria2c -p --lowest-speed-limit=4000 file.metalink
----------------------------------------------------------
[NOTE]
To pause a download, press Ctrl-C.
You can resume the transfer by running aria2c with the same argument in the same
directory.

Download several local metalink files
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
----------------------------------------
aria2c -j2 file1.metalink file2.metalink
----------------------------------------

Download only selected files using index
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-------------------------------------------
aria2c --select-file=1-4,8 file.metalink
-------------------------------------------
[NOTE]
The index is printed to the console using -S option.

Download a file using a local .metalink file with user preference
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
------------------------------------------------------------------------------
aria2c --metalink-location=jp,us --metalink-version=1.1 --metalink-language=en-US file.metalink
------------------------------------------------------------------------------

BitTorrent Download
~~~~~~~~~~~~~~~~~~~
Download files from remote BitTorrent file
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
------------------------------------------------------
aria2c --follow-torrent=mem "http://host/file.torrent"
------------------------------------------------------

Download using a local torrent file
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
---------------------------------------------
aria2c --max-upload-limit=40K file.torrent
---------------------------------------------
[NOTE]
--max-upload-limit specifies the max of upload rate.

[NOTE]
To pause a download, press Ctrl-C. You can resume the transfer by running aria2c with the same argument in the same directory.

Download using BitTorrent Magnet URI
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

------------------------------------------------------------------------------
aria2c "magnet:?xt=urn:btih:248D0A1CD08284299DE78D5C1ED359BB46717D8C&dn=aria2"
------------------------------------------------------------------------------

[NOTE]
Don't forget to quote BitTorrent Magnet URI which includes "&"
character with single(') or double(") quotation.

Download 2 torrents
^^^^^^^^^^^^^^^^^^^
--------------------------------------
aria2c -j2 file1.torrent file2.torrent
--------------------------------------

Download a file using torrent and HTTP/FTP server
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
------------------------------------------------------------
aria2c -Ttest.torrent "http://host1/file" "ftp://host2/file"
------------------------------------------------------------
[NOTE]
Downloading multi file torrent with HTTP/FTP is not supported.

Download only selected files using index(usually called "selectable download")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
---------------------------------------
aria2c --select-file=1-4,8 file.torrent
---------------------------------------
[NOTE]
The index is printed to the console using -S option.

Specify output filename
^^^^^^^^^^^^^^^^^^^^^^^

To specify output filename for BitTorrent downloads, you need to know
the index of file in torrent file using *-S* option. For example, the
output looks like this:

--------------------------
idx|path/length
===+======================
  1|dist/base-2.6.18.iso
   |99.9MiB
---+----------------------
  2|dist/driver-2.6.18.iso
   |169.0MiB
---+----------------------
--------------------------

To save 'dist/base-2.6.18.iso' in '/tmp/mydir/base.iso' and
'dist/driver-2.6.18.iso' in '/tmp/dir/driver.iso', use the following
command:

-----------------------------------------------------------------------------------------
aria2c --dir=/tmp --index-out=1=mydir/base.iso --index-out=2=dir/driver.iso file.torrent
-----------------------------------------------------------------------------------------

Change the listening port for incoming peer
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
---------------------------------------------------
aria2c --listen-port=7000-7001,8000 file.torrent
---------------------------------------------------
[NOTE]
Since aria2 doesn't configure firewall or router for port forwarding, it's up
to you to do it manually.

Specify the condition to stop program after torrent download finished
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-------------------------------------------------------
aria2c --seed-time=120 --seed-ratio=1.0 file.torrent
-------------------------------------------------------

[NOTE]
In the above example, the program exits when the 120 minutes has elapsed since download completed or seed ratio reaches 1.0.

Throttle upload speed
^^^^^^^^^^^^^^^^^^^^^
----------------------------------------------
aria2c --max-upload-limit=100K file.torrent
---------------------------------------------- 

Enable DHT
^^^^^^^^^^
---------------------------------------------------------
aria2c --enable-dht --dht-listen-port=6881 file.torrent
---------------------------------------------------------
[NOTE]
DHT uses udp port. Since aria2 doesn't configure firewall or router for port
forwarding, it's up to you to do it manually.

More advanced HTTP features
~~~~~~~~~~~~~~~~~~~~~~~~~~~
Load cookies
^^^^^^^^^^^^
--------------------------------------------------------
aria2c --load-cookies=cookies.txt "http://host/file.zip"
--------------------------------------------------------
[NOTE]
You can use Firefox/Mozilla's cookie file without modification.

Resume download started by web browsers or another programs
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-------------------------------------------------------
aria2c -c -s2 "http://host/partiallydownloadedfile.zip"
-------------------------------------------------------

Client certificate authorization for SSL/TLS
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
------------------------------------------------------------------------------------------
aria2c --certificate=/path/to/mycert.pem --private-key=/path/to/mykey.pem https://host/file
------------------------------------------------------------------------------------------
[NOTE]
The file specified in *--private-key* must be decrypted. The behavior when
encrypted one is given is undefined.

Verify peer in SSL/TLS using given CA certificates
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
------------------------------------------------------------------------------------------
aria2c --ca-certificate=/path/to/ca-certificates.crt --check-certificate https://host/file
------------------------------------------------------------------------------------------

And more advanced features
~~~~~~~~~~~~~~~~~~~~~~~~~~
Throttle download speed
^^^^^^^^^^^^^^^^^^^^^^^
-------------------------------------------------
aria2c --max-download-limit=100K file.metalink
-------------------------------------------------

Repair a damaged download
^^^^^^^^^^^^^^^^^^^^^^^^^
-----------------------
aria2c -V file.metalink
-----------------------
[NOTE]
This option is only available used with BitTorrent or metalink with chunk
checksums.

Drop connection if download speed is lower than specified value
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
------------------------------------------------
aria2c --lowest-speed-limit=10K file.metalink
------------------------------------------------

Parameterized URI support
^^^^^^^^^^^^^^^^^^^^^^^^^
You can specify set of parts:
-----------------------------------------------
aria2c -P "http://{host1,host2,host3}/file.iso"
-----------------------------------------------

You can specify numeric sequence:
---------------------------------------------
aria2c -Z -P "http://host/image[000-100].png"
---------------------------------------------

[NOTE]
-Z option is required if the all URIs don't point to the same file, such as the above example.

You can specify step counter:
-------------------------------------------
aria2c -Z -P "http://host/image[A-Z:2].png"
-------------------------------------------

Parallel downloads of arbitrary number of URL,metalink,torrent
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
--------------------------------------------------------------
aria2c -j3 -Z "http://host/file1" file2.torrent file3.metalink
--------------------------------------------------------------

BitTorrent Encryption
^^^^^^^^^^^^^^^^^^^^^
Encrypt whole payload using ARC4:
-------------------------------------------------------------------------
aria2c --bt-min-crypto-level=arc4 --bt-require-crypto=true file.torrent
-------------------------------------------------------------------------

SEE ALSO
--------
Project Web Site: http://aria2.sourceforge.net/

aria2 Wiki: http://sourceforge.net/apps/trac/aria2/wiki

Metalink Homepage: http://www.metalinker.org/

COPYRIGHT
---------
Copyright (C) 2006, 2010 Tatsuhiro Tsujikawa

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.

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.

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

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.