wget: Download Options
2.5 Download Options
====================
‘--bind-address=ADDRESS’
When making client TCP/IP connections, bind to ADDRESS on the local
machine. ADDRESS may be specified as a hostname or IP address.
This option can be useful if your machine is bound to multiple IPs.
‘--bind-dns-address=ADDRESS’
[libcares only] This address overrides the route for DNS requests.
If you ever need to circumvent the standard settings from
/etc/resolv.conf, this option together with ‘--dns-servers’ is your
friend. ADDRESS must be specified either as IPv4 or IPv6 address.
Wget needs to be built with libcares for this option to be
available.
‘--dns-servers=ADDRESSES’
[libcares only] The given address(es) override the standard
nameserver addresses, e.g. as configured in /etc/resolv.conf.
ADDRESSES may be specified either as IPv4 or IPv6 addresses,
comma-separated. Wget needs to be built with libcares for this
option to be available.
‘-t NUMBER’
‘--tries=NUMBER’
Set number of tries to NUMBER. Specify 0 or ‘inf’ for infinite
retrying. The default is to retry 20 times, with the exception of
fatal errors like “connection refused” or “not found” (404), which
are not retried.
‘-O FILE’
‘--output-document=FILE’
The documents will not be written to the appropriate files, but all
will be concatenated together and written to FILE. If ‘-’ is used
as FILE, documents will be printed to standard output, disabling
link conversion. (Use ‘./-’ to print to a file literally named
‘-’.)
Use of ‘-O’ is _not_ intended to mean simply “use the name FILE
instead of the one in the URL;” rather, it is analogous to shell
redirection: ‘wget -O file http://foo’ is intended to work like
‘wget -O - http://foo > file’; ‘file’ will be truncated
immediately, and _all_ downloaded content will be written there.
For this reason, ‘-N’ (for timestamp-checking) is not supported in
combination with ‘-O’: since FILE is always newly created, it will
always have a very new timestamp. A warning will be issued if this
combination is used.
Similarly, using ‘-r’ or ‘-p’ with ‘-O’ may not work as you expect:
Wget won’t just download the first file to FILE and then download
the rest to their normal names: _all_ downloaded content will be
placed in FILE. This was disabled in version 1.11, but has been
reinstated (with a warning) in 1.11.2, as there are some cases
where this behavior can actually have some use.
A combination with ‘-nc’ is only accepted if the given output file
does not exist.
Note that a combination with ‘-k’ is only permitted when
downloading a single document, as in that case it will just convert
all relative URIs to external ones; ‘-k’ makes no sense for
multiple URIs when they’re all being downloaded to a single file;
‘-k’ can be used only when the output is a regular file.
‘-nc’
‘--no-clobber’
If a file is downloaded more than once in the same directory,
Wget’s behavior depends on a few options, including ‘-nc’. In
certain cases, the local file will be “clobbered”, or overwritten,
upon repeated download. In other cases it will be preserved.
When running Wget without ‘-N’, ‘-nc’, ‘-r’, or ‘-p’, downloading
the same file in the same directory will result in the original
copy of FILE being preserved and the second copy being named
‘FILE.1’. If that file is downloaded yet again, the third copy
will be named ‘FILE.2’, and so on. (This is also the behavior with
‘-nd’, even if ‘-r’ or ‘-p’ are in effect.) When ‘-nc’ is
specified, this behavior is suppressed, and Wget will refuse to
download newer copies of ‘FILE’. Therefore, “‘no-clobber’” is
actually a misnomer in this mode—it’s not clobbering that’s
prevented (as the numeric suffixes were already preventing
clobbering), but rather the multiple version saving that’s
prevented.
When running Wget with ‘-r’ or ‘-p’, but without ‘-N’, ‘-nd’, or
‘-nc’, re-downloading a file will result in the new copy simply
overwriting the old. Adding ‘-nc’ will prevent this behavior,
instead causing the original version to be preserved and any newer
copies on the server to be ignored.
When running Wget with ‘-N’, with or without ‘-r’ or ‘-p’, the
decision as to whether or not to download a newer copy of a file
depends on the local and remote timestamp and size of the file
(⇒Time-Stamping). ‘-nc’ may not be specified at the same
time as ‘-N’.
A combination with ‘-O’/‘--output-document’ is only accepted if the
given output file does not exist.
Note that when ‘-nc’ is specified, files with the suffixes ‘.html’
or ‘.htm’ will be loaded from the local disk and parsed as if they
had been retrieved from the Web.
‘--backups=BACKUPS’
Before (over)writing a file, back up an existing file by adding a
‘.1’ suffix (‘_1’ on VMS) to the file name. Such backup files are
rotated to ‘.2’, ‘.3’, and so on, up to BACKUPS (and lost beyond
that).
‘--no-netrc’
Do not try to obtain credentials from ‘.netrc’ file. By default
‘.netrc’ file is searched for credentials in case none have been
passed on command line and authentication is required.
‘-c’
‘--continue’
Continue getting a partially-downloaded file. This is useful when
you want to finish up a download started by a previous instance of
Wget, or by another program. For instance:
wget -c ftp://sunsite.doc.ic.ac.uk/ls-lR.Z
If there is a file named ‘ls-lR.Z’ in the current directory, Wget
will assume that it is the first portion of the remote file, and
will ask the server to continue the retrieval from an offset equal
to the length of the local file.
Note that you don’t need to specify this option if you just want
the current invocation of Wget to retry downloading a file should
the connection be lost midway through. This is the default
behavior. ‘-c’ only affects resumption of downloads started
_prior_ to this invocation of Wget, and whose local files are still
sitting around.
Without ‘-c’, the previous example would just download the remote
file to ‘ls-lR.Z.1’, leaving the truncated ‘ls-lR.Z’ file alone.
If you use ‘-c’ on a non-empty file, and the server does not
support continued downloading, Wget will restart the download from
scratch and overwrite the existing file entirely.
Beginning with Wget 1.7, if you use ‘-c’ on a file which is of
equal size as the one on the server, Wget will refuse to download
the file and print an explanatory message. The same happens when
the file is smaller on the server than locally (presumably because
it was changed on the server since your last download
attempt)—because “continuing” is not meaningful, no download
occurs.
On the other side of the coin, while using ‘-c’, any file that’s
bigger on the server than locally will be considered an incomplete
download and only ‘(length(remote) - length(local))’ bytes will be
downloaded and tacked onto the end of the local file. This
behavior can be desirable in certain cases—for instance, you can
use ‘wget -c’ to download just the new portion that’s been appended
to a data collection or log file.
However, if the file is bigger on the server because it’s been
_changed_, as opposed to just _appended_ to, you’ll end up with a
garbled file. Wget has no way of verifying that the local file is
really a valid prefix of the remote file. You need to be
especially careful of this when using ‘-c’ in conjunction with
‘-r’, since every file will be considered as an "incomplete
download" candidate.
Another instance where you’ll get a garbled file if you try to use
‘-c’ is if you have a lame HTTP proxy that inserts a “transfer
interrupted” string into the local file. In the future a
“rollback” option may be added to deal with this case.
Note that ‘-c’ only works with FTP servers and with HTTP servers
that support the ‘Range’ header.
‘--start-pos=OFFSET’
Start downloading at zero-based position OFFSET. Offset may be
expressed in bytes, kilobytes with the ‘k’ suffix, or megabytes
with the ‘m’ suffix, etc.
‘--start-pos’ has higher precedence over ‘--continue’. When
‘--start-pos’ and ‘--continue’ are both specified, wget will emit a
warning then proceed as if ‘--continue’ was absent.
Server support for continued download is required, otherwise
‘--start-pos’ cannot help. See ‘-c’ for details.
‘--progress=TYPE’
Select the type of the progress indicator you wish to use. Legal
indicators are “dot” and “bar”.
The “bar” indicator is used by default. It draws an ASCII progress
bar graphics (a.k.a “thermometer” display) indicating the status of
retrieval. If the output is not a TTY, the “dot” bar will be used
by default.
Use ‘--progress=dot’ to switch to the “dot” display. It traces the
retrieval by printing dots on the screen, each dot representing a
fixed amount of downloaded data.
The progress TYPE can also take one or more parameters. The
parameters vary based on the TYPE selected. Parameters to TYPE are
passed by appending them to the type sperated by a colon (:) like
this: ‘--progress=TYPE:PARAMETER1:PARAMETER2’.
When using the dotted retrieval, you may set the “style” by
specifying the type as ‘dot:STYLE’. Different styles assign
different meaning to one dot. With the ‘default’ style each dot
represents 1K, there are ten dots in a cluster and 50 dots in a
line. The ‘binary’ style has a more “computer”-like orientation—8K
dots, 16-dots clusters and 48 dots per line (which makes for 384K
lines). The ‘mega’ style is suitable for downloading large
files—each dot represents 64K retrieved, there are eight dots in a
cluster, and 48 dots on each line (so each line contains 3M). If
‘mega’ is not enough then you can use the ‘giga’ style—each dot
represents 1M retrieved, there are eight dots in a cluster, and 32
dots on each line (so each line contains 32M).
With ‘--progress=bar’, there are currently two possible parameters,
FORCE and NOSCROLL.
When the output is not a TTY, the progress bar always falls back to
“dot”, even if ‘--progress=bar’ was passed to Wget during
invocation. This behaviour can be overridden and the “bar” output
forced by using the “force” parameter as ‘--progress=bar:force’.
By default, the ‘bar’ style progress bar scroll the name of the
file from left to right for the file being downloaded if the
filename exceeds the maximum length allotted for its display. In
certain cases, such as with ‘--progress=bar:force’, one may not
want the scrolling filename in the progress bar. By passing the
“noscroll” parameter, Wget can be forced to display as much of the
filename as possible without scrolling through it.
Note that you can set the default style using the ‘progress’
command in ‘.wgetrc’. That setting may be overridden from the
command line. For example, to force the bar output without
scrolling, use ‘--progress=bar:force:noscroll’.
‘--show-progress’
Force wget to display the progress bar in any verbosity.
By default, wget only displays the progress bar in verbose mode.
One may however, want wget to display the progress bar on screen in
conjunction with any other verbosity modes like ‘--no-verbose’ or
‘--quiet’. This is often a desired a property when invoking wget
to download several small/large files. In such a case, wget could
simply be invoked with this parameter to get a much cleaner output
on the screen.
This option will also force the progress bar to be printed to
‘stderr’ when used alongside the ‘--output-file’ option.
‘-N’
‘--timestamping’
Turn on time-stamping. ⇒Time-Stamping, for details.
‘--no-if-modified-since’
Do not send If-Modified-Since header in ‘-N’ mode. Send
preliminary HEAD request instead. This has only effect in ‘-N’
mode.
‘--no-use-server-timestamps’
Don’t set the local file’s timestamp by the one on the server.
By default, when a file is downloaded, its timestamps are set to
match those from the remote file. This allows the use of
‘--timestamping’ on subsequent invocations of wget. However, it is
sometimes useful to base the local file’s timestamp on when it was
actually downloaded; for that purpose, the
‘--no-use-server-timestamps’ option has been provided.
‘-S’
‘--server-response’
Print the headers sent by HTTP servers and responses sent by FTP
servers.
‘--spider’
When invoked with this option, Wget will behave as a Web “spider”,
which means that it will not download the pages, just check that
they are there. For example, you can use Wget to check your
bookmarks:
wget --spider --force-html -i bookmarks.html
This feature needs much more work for Wget to get close to the
functionality of real web spiders.
‘-T seconds’
‘--timeout=SECONDS’
Set the network timeout to SECONDS seconds. This is equivalent to
specifying ‘--dns-timeout’, ‘--connect-timeout’, and
‘--read-timeout’, all at the same time.
When interacting with the network, Wget can check for timeout and
abort the operation if it takes too long. This prevents anomalies
like hanging reads and infinite connects. The only timeout enabled
by default is a 900-second read timeout. Setting a timeout to 0
disables it altogether. Unless you know what you are doing, it is
best not to change the default timeout settings.
All timeout-related options accept decimal values, as well as
subsecond values. For example, ‘0.1’ seconds is a legal (though
unwise) choice of timeout. Subsecond timeouts are useful for
checking server response times or for testing network latency.
‘--dns-timeout=SECONDS’
Set the DNS lookup timeout to SECONDS seconds. DNS lookups that
don’t complete within the specified time will fail. By default,
there is no timeout on DNS lookups, other than that implemented by
system libraries.
‘--connect-timeout=SECONDS’
Set the connect timeout to SECONDS seconds. TCP connections that
take longer to establish will be aborted. By default, there is no
connect timeout, other than that implemented by system libraries.
‘--read-timeout=SECONDS’
Set the read (and write) timeout to SECONDS seconds. The “time” of
this timeout refers to “idle time”: if, at any point in the
download, no data is received for more than the specified number of
seconds, reading fails and the download is restarted. This option
does not directly affect the duration of the entire download.
Of course, the remote server may choose to terminate the connection
sooner than this option requires. The default read timeout is 900
seconds.
‘--limit-rate=AMOUNT’
Limit the download speed to AMOUNT bytes per second. Amount may be
expressed in bytes, kilobytes with the ‘k’ suffix, or megabytes
with the ‘m’ suffix. For example, ‘--limit-rate=20k’ will limit
the retrieval rate to 20KB/s. This is useful when, for whatever
reason, you don’t want Wget to consume the entire available
bandwidth.
This option allows the use of decimal numbers, usually in
conjunction with power suffixes; for example, ‘--limit-rate=2.5k’
is a legal value.
Note that Wget implements the limiting by sleeping the appropriate
amount of time after a network read that took less time than
specified by the rate. Eventually this strategy causes the TCP
transfer to slow down to approximately the specified rate.
However, it may take some time for this balance to be achieved, so
don’t be surprised if limiting the rate doesn’t work well with very
small files.
‘-w SECONDS’
‘--wait=SECONDS’
Wait the specified number of seconds between the retrievals. Use
of this option is recommended, as it lightens the server load by
making the requests less frequent. Instead of in seconds, the time
can be specified in minutes using the ‘m’ suffix, in hours using
‘h’ suffix, or in days using ‘d’ suffix.
Specifying a large value for this option is useful if the network
or the destination host is down, so that Wget can wait long enough
to reasonably expect the network error to be fixed before the
retry. The waiting interval specified by this function is
influenced by ‘--random-wait’, which see.
‘--waitretry=SECONDS’
If you don’t want Wget to wait between _every_ retrieval, but only
between retries of failed downloads, you can use this option. Wget
will use “linear backoff”, waiting 1 second after the first failure
on a given file, then waiting 2 seconds after the second failure on
that file, up to the maximum number of SECONDS you specify.
By default, Wget will assume a value of 10 seconds.
‘--random-wait’
Some web sites may perform log analysis to identify retrieval
programs such as Wget by looking for statistically significant
similarities in the time between requests. This option causes the
time between requests to vary between 0.5 and 1.5 * WAIT seconds,
where WAIT was specified using the ‘--wait’ option, in order to
mask Wget’s presence from such analysis.
A 2001 article in a publication devoted to development on a popular
consumer platform provided code to perform this analysis on the
fly. Its author suggested blocking at the class C address level to
ensure automated retrieval programs were blocked despite changing
DHCP-supplied addresses.
The ‘--random-wait’ option was inspired by this ill-advised
recommendation to block many unrelated users from a web site due to
the actions of one.
‘--no-proxy’
Don’t use proxies, even if the appropriate ‘*_proxy’ environment
variable is defined.
⇒Proxies, for more information about the use of proxies with
Wget.
‘-Q QUOTA’
‘--quota=QUOTA’
Specify download quota for automatic retrievals. The value can be
specified in bytes (default), kilobytes (with ‘k’ suffix), or
megabytes (with ‘m’ suffix).
Note that quota will never affect downloading a single file. So if
you specify ‘wget -Q10k https://example.com/ls-lR.gz’, all of the
‘ls-lR.gz’ will be downloaded. The same goes even when several
URLs are specified on the command-line. The quota is checked only
at the end of each downloaded file, so it will never result in a
partially downloaded file. Thus you may safely type ‘wget -Q2m -i
sites’—download will be aborted after the file that exhausts the
quota is completely downloaded.
Setting quota to 0 or to ‘inf’ unlimits the download quota.
‘--no-dns-cache’
Turn off caching of DNS lookups. Normally, Wget remembers the IP
addresses it looked up from DNS so it doesn’t have to repeatedly
contact the DNS server for the same (typically small) set of hosts
it retrieves from. This cache exists in memory only; a new Wget
run will contact DNS again.
However, it has been reported that in some situations it is not
desirable to cache host names, even for the duration of a
short-running application like Wget. With this option Wget issues
a new DNS lookup (more precisely, a new call to ‘gethostbyname’ or
‘getaddrinfo’) each time it makes a new connection. Please note
that this option will _not_ affect caching that might be performed
by the resolving library or by an external caching layer, such as
NSCD.
If you don’t understand exactly what this option does, you probably
won’t need it.
‘--restrict-file-names=MODES’
Change which characters found in remote URLs must be escaped during
generation of local filenames. Characters that are “restricted” by
this option are escaped, i.e. replaced with ‘%HH’, where ‘HH’ is
the hexadecimal number that corresponds to the restricted
character. This option may also be used to force all alphabetical
cases to be either lower- or uppercase.
By default, Wget escapes the characters that are not valid or safe
as part of file names on your operating system, as well as control
characters that are typically unprintable. This option is useful
for changing these defaults, perhaps because you are downloading to
a non-native partition, or because you want to disable escaping of
the control characters, or you want to further restrict characters
to only those in the ASCII range of values.
The MODES are a comma-separated set of text values. The acceptable
values are ‘unix’, ‘windows’, ‘nocontrol’, ‘ascii’, ‘lowercase’,
and ‘uppercase’. The values ‘unix’ and ‘windows’ are mutually
exclusive (one will override the other), as are ‘lowercase’ and
‘uppercase’. Those last are special cases, as they do not change
the set of characters that would be escaped, but rather force local
file paths to be converted either to lower- or uppercase.
When “unix” is specified, Wget escapes the character ‘/’ and the
control characters in the ranges 0–31 and 128–159. This is the
default on Unix-like operating systems.
When “windows” is given, Wget escapes the characters ‘\’, ‘|’, ‘/’,
‘:’, ‘?’, ‘"’, ‘*’, ‘<’, ‘>’, and the control characters in the
ranges 0–31 and 128–159. In addition to this, Wget in Windows mode
uses ‘+’ instead of ‘:’ to separate host and port in local file
names, and uses ‘@’ instead of ‘?’ to separate the query portion of
the file name from the rest. Therefore, a URL that would be saved
as ‘www.xemacs.org:4300/search.pl?input=blah’ in Unix mode would be
saved as ‘www.xemacs.org+4300/search.pl@input=blah’ in Windows
mode. This mode is the default on Windows.
If you specify ‘nocontrol’, then the escaping of the control
characters is also switched off. This option may make sense when
you are downloading URLs whose names contain UTF-8 characters, on a
system which can save and display filenames in UTF-8 (some possible
byte values used in UTF-8 byte sequences fall in the range of
values designated by Wget as “controls”).
The ‘ascii’ mode is used to specify that any bytes whose values are
outside the range of ASCII characters (that is, greater than 127)
shall be escaped. This can be useful when saving filenames whose
encoding does not match the one used locally.
‘-4’
‘--inet4-only’
‘-6’
‘--inet6-only’
Force connecting to IPv4 or IPv6 addresses. With ‘--inet4-only’ or
‘-4’, Wget will only connect to IPv4 hosts, ignoring AAAA records
in DNS, and refusing to connect to IPv6 addresses specified in
URLs. Conversely, with ‘--inet6-only’ or ‘-6’, Wget will only
connect to IPv6 hosts and ignore A records and IPv4 addresses.
Neither options should be needed normally. By default, an
IPv6-aware Wget will use the address family specified by the host’s
DNS record. If the DNS responds with both IPv4 and IPv6 addresses,
Wget will try them in sequence until it finds one it can connect
to. (Also see ‘--prefer-family’ option described below.)
These options can be used to deliberately force the use of IPv4 or
IPv6 address families on dual family systems, usually to aid
debugging or to deal with broken network configuration. Only one
of ‘--inet6-only’ and ‘--inet4-only’ may be specified at the same
time. Neither option is available in Wget compiled without IPv6
support.
‘--prefer-family=none/IPv4/IPv6’
When given a choice of several addresses, connect to the addresses
with specified address family first. The address order returned by
DNS is used without change by default.
This avoids spurious errors and connect attempts when accessing
hosts that resolve to both IPv6 and IPv4 addresses from IPv4
networks. For example, ‘www.kame.net’ resolves to
‘2001:200:0:8002:203:47ff:fea5:3085’ and to ‘203.178.141.194’.
When the preferred family is ‘IPv4’, the IPv4 address is used
first; when the preferred family is ‘IPv6’, the IPv6 address is
used first; if the specified value is ‘none’, the address order
returned by DNS is used without change.
Unlike ‘-4’ and ‘-6’, this option doesn’t inhibit access to any
address family, it only changes the _order_ in which the addresses
are accessed. Also note that the reordering performed by this
option is “stable”—it doesn’t affect order of addresses of the same
family. That is, the relative order of all IPv4 addresses and of
all IPv6 addresses remains intact in all cases.
‘--retry-connrefused’
Consider “connection refused” a transient error and try again.
Normally Wget gives up on a URL when it is unable to connect to the
site because failure to connect is taken as a sign that the server
is not running at all and that retries would not help. This option
is for mirroring unreliable sites whose servers tend to disappear
for short periods of time.
‘--user=USER’
‘--password=PASSWORD’
Specify the username USER and password PASSWORD for both FTP and
HTTP file retrieval. These parameters can be overridden using the
‘--ftp-user’ and ‘--ftp-password’ options for FTP connections and
the ‘--http-user’ and ‘--http-password’ options for HTTP
connections.
‘--ask-password’
Prompt for a password for each connection established. Cannot be
specified when ‘--password’ is being used, because they are
mutually exclusive.
‘--use-askpass=COMMAND’
Prompt for a user and password using the specified command. If no
command is specified then the command in the environment variable
WGET_ASKPASS is used. If WGET_ASKPASS is not set then the command
in the environment variable SSH_ASKPASS is used.
You can set the default command for use-askpass in the ‘.wgetrc’.
That setting may be overridden from the command line.
‘--no-iri’
Turn off internationalized URI (IRI) support. Use ‘--iri’ to turn
it on. IRI support is activated by default.
You can set the default state of IRI support using the ‘iri’
command in ‘.wgetrc’. That setting may be overridden from the
command line.
‘--local-encoding=ENCODING’
Force Wget to use ENCODING as the default system encoding. That
affects how Wget converts URLs specified as arguments from locale
to UTF-8 for IRI support.
Wget use the function ‘nl_langinfo()’ and then the ‘CHARSET’
environment variable to get the locale. If it fails, ASCII is
used.
You can set the default local encoding using the ‘local_encoding’
command in ‘.wgetrc’. That setting may be overridden from the
command line.
‘--remote-encoding=ENCODING’
Force Wget to use ENCODING as the default remote server encoding.
That affects how Wget converts URIs found in files from remote
encoding to UTF-8 during a recursive fetch. This options is only
useful for IRI support, for the interpretation of non-ASCII
characters.
For HTTP, remote encoding can be found in HTTP ‘Content-Type’
header and in HTML ‘Content-Type http-equiv’ meta tag.
You can set the default encoding using the ‘remoteencoding’ command
in ‘.wgetrc’. That setting may be overridden from the command
line.
‘--unlink’
Force Wget to unlink file instead of clobbering existing file.
This option is useful for downloading to the directory with
hardlinks.
Info Catalog
wget: Logging and Input File Options
wget: Invoking
wget: Directory Options