This option sets flag which allows hook command invocation after hash
check (see -V option) in BitTorrent download. By default, when hash
check succeeds, the command given by --on-bt-download-complete is
executed. To disable this action, give false to this option.
Set the maximum socket receive buffer in bytes. Specifing 0 will
disable this option. This value will be set to socket file descriptor
using SO_RCVBUF socket option with setsockopt() call.
See GH-487 about the usecase of this option
See http://standards.freedesktop.org/basedir-spec/latest/ for further
details. This implementation decides the default based on whether a
file exists at the legacy location, if it doesn't, it picks the
XDG-conforming location instead.
Set checksum for SSH host public key. Use same syntax with --checksum
option. TYPE is hash type. The supported hash type is sha-1 or
md5. DIGEST is hex digest. For example:
sha-1=b030503d4de4539dc7885e6f0f5e256704edf4c3. This option can be
used to validate server's public key when SFTP is used. If this
option is not set, which is default, no validation takes place.
This option requires BitTorrent message payload encryption with
arc4. This is a shorthand of --bt-requre-crypto
--bt-min-crypto-level=arc4. If true is given, deny legacy BitTorrent
handshake and only use Obfuscation handshake and always encrypt
message payload. This option defaults to false.
This option excludes seed only downloads when counting concurrent
active downloads (-j option). This means that if -j3 is given and
this option is turned on and 3 downloads are active and one of those
enters seed mode, then it is excluded from active download count (thus
it becomes 2), and the next download waiting in queue gets started.
But be aware that seeding item is still recognized as active download
in RPC method.
This option pauses downloads created as a result of metadata
download. There are 3 types of metadata downloads in aria2: (1)
downloading .torrent file. (2) downloading torrent metadata using
magnet link. (3) downloading metalink file. These metadata downloads
will generate downloads using their metadata. This option pauses these
subsequent downloads.
This change changes the behavior of --bt-max-open-files. Previously,
it specifies the maximum number of opened files for each multi-file
download. Since it is more useful to limit the number globally, the
option now specifies the global limit. This change suggests that
aria2.changeOption() method now ignores --bt-max-open-files and
aria2.changeGlobalOption now reads it and dynamically change the
limit.
LibUV event will use the best available polling method on a system, kind
of like aria2 does already with the different *EventPoll
implementations.
However, libuv may support different/newer polling mechanisms; for
example on Windows it will use IO Completion Ports which are superior to
select() ;)
The IPv6 asynchronous name resolver is enabled if the host has at
least one interface with IPv6 address configured (the loopback address
will not be counted), which is roughly the same behaviour of the
standard getaddrinfo(3). To disable IPv6 asynchronous name resolver,
use --disable-ipv6.
--save-session-interval option saves error/unfinished downloads to a
file specified by --save-session option every SEC seconds. If 0 is
given, file will be saved only when aria2 exits.
This option sets GID manually. aria2 identifies each download by the
ID called GID. The GID must be hex string of 16 characters, thus
[0-9a-zA-Z] are allowed and leading zeros must not be stripped. The
GID all 0 is reserved and must not be used. The GID must be unique,
otherwise error is reported and the download is not added. This
option is useful when restoring the sessions saved using
--save-session option. If this option is not used, new GID is
generated by aria2.
This option enables disk cache. If SIZE is 0, the disk cache is
disabled. This feature caches the downloaded data in memory, which
grows to at most SIZE bytes. The cache storage is created for aria2
instance and shared by all downloads. The one advantage of the disk
cache is reduce the disk seek time because the data is written in
larger unit and it is reordered by the offset of the file. If the
underlying file is heavily fragmented it is not the case.
I tried CreateFile but the subsequent ReadFile fails with Access
Denied if sparse file is read on NTFS. I mostly reverted previous
changes and use _wsopen with read/write share enabled instead of
CreateFile.
This change also includes --enable-mmap support for MinGW32
build. Memory mapped file may be useful for 64-bits OS and lots of
RAM. Currently, FlushViewOfFile is not called during the download, so
it is slightly vulnerable against sudden power loss. I found lots of
read when resuming download due to page fault. So for now it is useful
for the initial download. I recommend not to use
--file-allocation=prealloc with --enable-mmap for MinGW32, because it
triggers page faults even in the initial download. Anyway, the option
is experimental.
--force-save option saves download with --save-session option even if
the download is completed or removed. This may be useful to save
BitTorrent seeding which is recognized as completed state. The
default value is false.
Tatsuhiro Tsujikawa