getopt to process command-line arguments, every option has a long form along with the short one. Long options are more convenient to remember, but take time to type. You may freely mix different option styles, or specify options after the command-line arguments. Thus you may write:
The space between the option accepting an argument and the argument may be omitted. Instead of -o log you can write -olog.
Since the options can be specified after the arguments, you may terminate them with --. So the following will try to download URL -x, reporting failure to log:
The options that accept comma-separated lists all respect the convention that specifying an empty list clears its value. This can be useful to clear the .wgetrc settings. For instance, if your .wgetrc sets "exclude_directories" to /cgi-bin, the following example will first reset it, and then set it to exclude /~nobody and /~somebody. You can also clear the lists in .wgetrc.
Unless stated otherwise, it is assumed that the default behavior is the opposite of what the option accomplishes. For example, the documented existence of --follow-ftp assumes that the default is to not follow FTP links from HTML pages.
- 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.
- [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.
- [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
- 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
- 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.
- 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. -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.
- 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).
- 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 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.
- 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 invokation. 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.
- 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 --logfile option.
- Turn on time-stamping.
- Do not send If-Modified-Since header in -N mode. Send preliminary HEAD request instead. This has only effect in -N mode.
- 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.
- Print the headers sent by HTTP servers and responses sent by FTP servers.
- 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
- 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.
- 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.
- 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.
- 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 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 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.
- 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.
- 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.
- Don't use proxies, even if the appropriate *_proxy environment variable is defined.
- -Q 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. However, quota is respected when retrieving either recursively, or from an input file. Thus you may safely type wget -Q2m -i sites---download will be aborted when the quota is exceeded.
Setting quota to 0 or to inf unlimits the download quota.
- 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.
- 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.
- 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.
- 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 22.214.171.124. 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.
- 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.
- 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.
- Prompt for a password for each connection established. Cannot be specified when --password is being used, because they are mutually exclusive.
- 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.
- 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.
- 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.
- Force Wget to unlink file instead of clobbering existing file. This option is useful for downloading to the directory with hardlinks.
- Use name as the default file name when it isn't known (i.e., for URLs that end in a slash), instead of index.html.
- If a file of type application/xhtml+xml or text/html is downloaded and the URL does not end with the regexp \.[Hh][Tt][Mm][Ll]?, this option will cause the suffix .html to be appended to the local filename. This is useful, for instance, when you're mirroring a remote site that uses .asp pages, but you want the mirrored pages to be viewable on your stock Apache server. Another good use for this is when you're downloading CGI-generated materials. A URL like http://site.com/article.cgi?25 will be saved as article.cgi?25.html.
Note that filenames changed in this way will be re-downloaded every time you re-mirror a site, because Wget can't tell that the local X.html file corresponds to remote URL X (since it doesn't yet know that the URL produces output of type text/html or application/xhtml+xml.
As of version 1.12, Wget will also ensure that any downloaded files of type text/css end in the suffix .css, and the option was renamed from --html-extension, to better reflect its new behavior. The old option name is still acceptable, but should now be considered deprecated.
At some point in the future, this option may well be expanded to include suffixes for other types of content, including content types that are not parsed by Wget.
- Specify the username user and password password on an HTTP server. According to the type of the challenge, Wget will encode them using either the "basic" (insecure), the "digest", or the Windows "NTLM" authentication scheme.
Another way to specify username and password is in the URL itself. Either method reveals your password to anyone who bothers to run "ps". To prevent the passwords from being seen, store them in .wgetrc or .netrc, and make sure to protect those files from other users with "chmod". If the passwords are really important, do not leave them lying in those files either---edit the files and delete them after Wget has started the download.
- Turn off the ``keep-alive'' feature for HTTP downloads. Normally, Wget asks the server to keep the connection open so that, when you download more than one document from the same server, they get transferred over the same TCP connection. This saves time and at the same time reduces the load on the server.
This option is useful when, for some reason, persistent (keep-alive) connections don't work for you, for example due to a server bug or due to the inability of server-side scripts to cope with the connections.
- Disable server-side cache. In this case, Wget will send the remote server an appropriate directive (Pragma: no-cache) to get the file from the remote service, rather than returning the cached version. This is especially useful for retrieving and flushing out-of-date documents on proxy servers.
Caching is allowed by default.
- --load-cookies file
- Load cookies from file before the first HTTP retrieval. file is a textual file in the format originally used by Netscape's cookies.txt file.
You will typically use this option when mirroring sites that require that you be logged in to access some or all of their content. The login process typically works by the web server issuing an HTTP cookie upon receiving and verifying your credentials. The cookie is then resent by the browser when accessing that part of the site, and so proves your identity.
Mirroring such a site requires Wget to send the same cookies your browser sends when communicating with the site. This is achieved by --load-cookies---simply point Wget to the location of the cookies.txt file, and it will send the same cookies your browser would send in the same situation. Different browsers keep textual cookie files in different locations:
- "Netscape 4.x."
- The cookies are in ~/.netscape/cookies.txt.
- "Mozilla and Netscape 6.x."
- Mozilla's cookie file is also named cookies.txt, located somewhere under ~/.mozilla, in the directory of your profile. The full path usually ends up looking somewhat like ~/.mozilla/default/some-weird-string/cookies.txt.
- "Internet Explorer."
- You can produce a cookie file Wget can use by using the File menu, Import and Export, Export Cookies. This has been tested with Internet Explorer 5; it is not guaranteed to work with earlier versions.
- "Other browsers."
- If you are using a different browser to create your cookies, --load-cookies will only work if you can locate or produce a cookie file in the Netscape format that Wget expects.
If you cannot use --load-cookies, there might still be an alternative. If your browser supports a ``cookie manager'', you can use it to view the cookies used when accessing the site you're mirroring. Write down the name and value of the cookie, and manually instruct Wget to send those cookies, bypassing the ``official'' cookie support:
wget --no-cookies --header "Cookie: <name>=<value>"
- --save-cookies file
- Save cookies to file before exiting. This will not save cookies that have expired or that have no expiry time (so-called ``session cookies''), but also see --keep-session-cookies.
- When specified, causes --save-cookies to also save session cookies. Session cookies are normally not saved because they are meant to be kept in memory and forgotten when you exit the browser. Saving them is useful on sites that require you to log in or to visit the home page before you can access some pages. With this option, multiple Wget runs are considered a single browser session as far as the site is concerned.
Since the cookie file format does not normally carry session cookies, Wget marks them with an expiry timestamp of 0. Wget's --load-cookies recognizes those as session cookies, but it might confuse other browsers. Also note that cookies so loaded will be treated as other session cookies, which means that if you want --save-cookies to preserve them again, you must use --keep-session-cookies again.
- Unfortunately, some HTTP servers (CGI programs, to be more precise) send out bogus "Content-Length" headers, which makes Wget go wild, as it thinks not all the document was retrieved. You can spot this syndrome if Wget retries getting the same document again and again, each time claiming that the (otherwise normal) connection has closed on the very same byte.
With this option, Wget will ignore the "Content-Length" header---as if it never existed.
- Send header-line along with the rest of the headers in each HTTP request. The supplied header is sent as-is, which means it must contain name and value separated by colon, and must not contain newlines.
You may define more than one additional header by specifying --header more than once.
wget --header='Accept-Charset: iso-8859-2' \ --header='Accept-Language: hr' \ http://fly.srk.fer.hr/
Specification of an empty string as the header value will clear all previous user-defined headers.
As of Wget 1.10, this option can be used to override headers otherwise generated automatically. This example instructs Wget to connect to localhost, but to specify foo.bar in the "Host" header:
wget --header="Host: foo.bar" http://localhost/
In versions of Wget prior to 1.10 such use of --header caused sending of duplicate headers.
- Specifies the maximum number of redirections to follow for a resource. The default is 20, which is usually far more than necessary. However, on those occasions where you want to allow more (or fewer), this is the option to use.
- Specify the username user and password password for authentication on a proxy server. Wget will encode them using the "basic" authentication scheme.
Security considerations similar to those with --http-password pertain here as well.
- Include `Referer: url' header in HTTP request. Useful for retrieving documents with server-side processing that assume they are always being retrieved by interactive web browsers and only come out properly when Referer is set to one of the pages that point to them.
- Save the headers sent by the HTTP server to the file, preceding the actual contents, with an empty line as the separator.
- -U agent-string
- Identify as agent-string to the HTTP server.
The HTTP protocol allows the clients to identify themselves using a "User-Agent" header field. This enables distinguishing the WWW software, usually for statistical purposes or for tracing of protocol violations. Wget normally identifies as Wget/version, version being the current version number of Wget.
However, some sites have been known to impose the policy of tailoring the output according to the "User-Agent"-supplied information. While this is not such a bad idea in theory, it has been abused by servers denying information to clients other than (historically) Netscape or, more frequently, Microsoft Internet Explorer. This option allows you to change the "User-Agent" line issued by Wget. Use of this option is discouraged, unless you really know what you are doing.
Specifying empty user agent with --user-agent="" instructs Wget not to send the "User-Agent" header in HTTP requests.
- Use POST as the method for all HTTP requests and send the specified data in the request body. --post-data sends string as data, whereas --post-file sends the contents of file. Other than that, they work in exactly the same way. In particular, they both expect content of the form "key1=value1&key2=value2", with percent-encoding for special characters; the only difference is that one expects its content as a command-line parameter and the other accepts its content from a file. In particular, --post-file is not for transmitting files as form attachments: those must appear as "key=value" data (with appropriate percent-coding) just like everything else. Wget does not currently support "multipart/form-data" for transmitting POST data; only "application/x-www-form-urlencoded". Only one of --post-data and --post-file should be specified.
Please note that wget does not require the content to be of the form "key1=value1&key2=value2", and neither does it test for it. Wget will simply transmit whatever data is provided to it. Most servers however expect the POST data to be in the above format when processing HTML Forms.
When sending a POST request using the --post-file option, Wget treats the file as a binary file and will send every character in the POST request without stripping trailing newline or formfeed characters. Any other control characters in the text will also be sent as-is in the POST request.
Please be aware that Wget needs to know the size of the POST data in advance. Therefore the argument to "--post-file" must be a regular file; specifying a FIFO or something like /dev/stdin won't work. It's not quite clear how to work around this limitation inherent in HTTP/1.0. Although HTTP/1.1 introduces chunked transfer that doesn't require knowing the request length in advance, a client can't use chunked unless it knows it's talking to an HTTP/1.1 server. And it can't know that until it receives a response, which in turn requires the request to have been completed --- a chicken-and-egg problem.
Note: As of version 1.15 if Wget is redirected after the POST request is completed, its behaviour will depend on the response code returned by the server. In case of a 301 Moved Permanently, 302 Moved Temporarily or 307 Temporary Redirect, Wget will, in accordance with RFC2616, continue to send a POST request. In case a server wants the client to change the Request method upon redirection, it should send a 303 See Other response code.
This example shows how to log in to a server using POST and then proceed to download the desired pages, presumably only accessible to authorized users:
# Log in to the server. This can be done only once. wget --save-cookies cookies.txt \ --post-data 'user=foo&password=bar' \ http://example.com/auth.php # Now grab the page or pages we care about. wget --load-cookies cookies.txt \ -p http://example.com/interesting/article.php
If the server is using session cookies to track user authentication, the above will not work because --save-cookies will not save them (and neither will browsers) and the cookies.txt file will be empty. In that case use --keep-session-cookies along with --save-cookies to force saving of session cookies.
- For the purpose of RESTful scripting, Wget allows sending of other HTTP Methods without the need to explicitly set them using --header=Header-Line. Wget will use whatever string is passed to it after --method as the HTTP Method to the server.
- Must be set when additional data needs to be sent to the server along with the Method specified using --method. --body-data sends string as data, whereas --body-file sends the contents of file. Other than that, they work in exactly the same way.
Currently, --body-file is not for transmitting files as a whole. Wget does not currently support "multipart/form-data" for transmitting data; only "application/x-www-form-urlencoded". In the future, this may be changed so that wget sends the --body-file as a complete file instead of sending its contents to the server. Please be aware that Wget needs to know the contents of BODY Data in advance, and hence the argument to --body-file should be a regular file. See --post-file for a more detailed explanation. Only one of --body-data and --body-file should be specified.
If Wget is redirected after the request is completed, Wget will suspend the current method and send a GET request till the redirection is completed. This is true for all redirection response codes except 307 Temporary Redirect which is used to explicitly specify that the request method should not change. Another exception is when the method is set to "POST", in which case the redirection rules specified under --post-data are followed.
- If this is set to on, experimental (not fully-functional) support for "Content-Disposition" headers is enabled. This can currently result in extra round-trips to the server for a "HEAD" request, and is known to suffer from a few bugs, which is why it is not currently enabled by default.
This option is useful for some file-downloading CGI programs that use "Content-Disposition" headers to describe what the name of a downloaded file should be.
- If this is set to on, wget will not skip the content when the server responds with a http status code that indicates error.
- If this is set to on, on a redirect the last component of the redirection URL will be used as the local file name. By default it is used the last component in the original URL.
- If this option is given, Wget will send Basic HTTP authentication information (plaintext username and password) for all requests, just like Wget 1.10.2 and prior did by default.
Use of this option is not recommended, and is intended only to support some few obscure servers, which never send HTTP authentication challenges, but accept unsolicited auth info, say, in addition to form-based authentication.
library. The current default is GnuTLS. In addition, Wget also supports
Strict Transport Security). If Wget is compiled without
support, none of these options are available.
- Choose the secure protocol to be used. Legal values are auto, SSLv2, SSLv3, TLSv1, TLSv1_1, TLSv1_2 and PFS. If auto is used, the SSL library is given the liberty of choosing the appropriate protocol automatically, which is achieved by sending a TLSv1 greeting. This is the default.
Specifying SSLv2, SSLv3, TLSv1, TLSv1_1 or TLSv1_2 forces the use of the corresponding protocol. This is useful when talking to old and buggy SSL server implementations that make it hard for the underlying SSL library to choose the correct protocol version. Fortunately, such servers are quite rare.
Specifying PFS enforces the use of the so-called Perfect Forward Security cipher suites. In short, PFS adds security by creating a one-time key for each SSL connection. It has a bit more CPU impact on client and server. We use known to be secure ciphers (e.g. no MD4) and the TLS protocol.
- When in recursive mode, only HTTPS links are followed.
- Don't check the server certificate against the available certificate authorities. Also don't require the URL host name to match the common name presented by the certificate.
As of Wget 1.10, the default is to verify the server's certificate against the recognized certificate authorities, breaking the SSL handshake and aborting the download if the verification fails. Although this provides more secure downloads, it does break interoperability with some sites that worked with previous Wget versions, particularly those using self-signed, expired, or otherwise invalid certificates. This option forces an ``insecure'' mode of operation that turns the certificate verification errors into warnings and allows you to proceed.
If you encounter ``certificate verification'' errors or ones saying that ``common name doesn't match requested host name'', you can use this option to bypass the verification and proceed with the download. Only use this option if you are otherwise convinced of the site's authenticity, or if you really don't care about the validity of its certificate. It is almost always a bad idea not to check the certificates when transmitting confidential or important data. For self-signed/internal certificates, you should download the certificate and verify against that instead of forcing this insecure mode. If you are really sure of not desiring any certificate verification, you can specify --check-certificate=quiet to tell wget to not print any warning about invalid certificates, albeit in most cases this is the wrong thing to do.
- Use the client certificate stored in file. This is needed for servers that are configured to require certificates from the clients that connect to them. Normally a certificate is not required and this switch is optional.
- Specify the type of the client certificate. Legal values are PEM (assumed by default) and DER, also known as ASN1.
- Read the private key from file. This allows you to provide the private key in a file separate from the certificate.
- Specify the type of the private key. Accepted values are PEM (the default) and DER.
- Use file as the file with the bundle of certificate authorities (``CA'') to verify the peers. The certificates must be in PEM format.
Without this option Wget looks for CA certificates at the system-specified locations, chosen at OpenSSL installation time.
- Specifies directory containing CA certificates in PEM format. Each file contains one CA certificate, and the file name is based on a hash value derived from the certificate. This is achieved by processing a certificate directory with the "c_rehash" utility supplied with OpenSSL. Using --ca-directory is more efficient than --ca-certificate when many certificates are installed because it allows Wget to fetch certificates on demand.
Without this option Wget looks for CA certificates at the system-specified locations, chosen at OpenSSL installation time.
- Specifies a CRL file in file. This is needed for certificates that have been revocated by the CAs.
- Tells wget to use the specified public key file (or hashes) to verify the peer. This can be a path to a file which contains a single public key in PEM or DER format, or any number of base64 encoded sha256 hashes preceded by ``sha256//'' and separated by ``;''
When negotiating a TLS or SSL connection, the server sends a certificate indicating its identity. A public key is extracted from this certificate and if it does not exactly match the public key(s) provided to this option, wget will abort the connection before sending or receiving any data.
- [OpenSSL and LibreSSL only] Use file as the source of random data for seeding the pseudo-random number generator on systems without /dev/urandom.
On such systems the SSL library needs an external source of randomness to initialize. Randomness may be provided by EGD (see --egd-file below) or read from an external source specified by the user. If this option is not specified, Wget looks for random data in $RANDFILE or, if that is unset, in $HOME/.rnd.
If you're getting the ``Could not seed OpenSSL PRNG; disabling SSL.'' error, you should provide random data using some of the methods described above.
- [OpenSSL only] Use file as the EGD socket. EGD stands for Entropy Gathering Daemon, a user-space program that collects data from various unpredictable system sources and makes it available to other programs that might need it. Encryption software, such as the SSL library, needs sources of non-repeating randomness to seed the random number generator used to produce cryptographically strong keys.
OpenSSL allows the user to specify his own source of entropy using the "RAND_FILE" environment variable. If this variable is unset, or if the specified file does not produce enough randomness, OpenSSL will read random data from EGD socket specified using this option.
If this option is not specified (and the equivalent startup command is not used), EGD is never contacted. EGD is not needed on modern Unix systems that support /dev/urandom.
- Wget supports HSTS (HTTP Strict Transport Security, RFC 6797) by default. Use --no-hsts to make Wget act as a non-HSTS-compliant UA. As a consequence, Wget would ignore all the "Strict-Transport-Security" headers, and would not enforce any existing HSTS policy.
- By default, Wget stores its HSTS database in ~/.wget-hsts. You can use --hsts-file to override this. Wget will use the supplied file as the HSTS database. Such file must conform to the correct HSTS database format used by Wget. If Wget cannot parse the provided file, the behaviour is unspecified.
The Wget's HSTS database is a plain text file. Each line contains an HSTS entry (ie. a site that has issued a "Strict-Transport-Security" header and that therefore has specified a concrete HSTS policy to be applied). Lines starting with a dash ("#") are ignored by Wget. Please note that in spite of this convenient human-readability hand-hacking the HSTS database is generally not a good idea.
An HSTS entry line consists of several fields separated by one or more whitespace:
"<hostname> SP [<port>] SP <include subdomains> SP <created> SP <max-age>"
The hostname and port fields indicate the hostname and port to which the given HSTS policy applies. The port field may be zero, and it will, in most of the cases. That means that the port number will not be taken into account when deciding whether such HSTS policy should be applied on a given request (only the hostname will be evaluated). When port is different to zero, both the target hostname and the port will be evaluated and the HSTS policy will only be applied if both of them match. This feature has been included for testing/development purposes only. The Wget testsuite (in testenv/) creates HSTS databases with explicit ports with the purpose of ensuring Wget's correct behaviour. Applying HSTS policies to ports other than the default ones is discouraged by RFC 6797 (see Appendix B ``Differences between HSTS Policy and Same-Origin Policy''). Thus, this functionality should not be used in production environments and port will typically be zero. The last three fields do what they are expected to. The field include_subdomains can either be 1 or 0 and it signals whether the subdomains of the target domain should be part of the given HSTS policy as well. The created and max-age fields hold the timestamp values of when such entry was created (first seen by Wget) and the HSTS-defined value 'max-age', which states how long should that HSTS policy remain active, measured in seconds elapsed since the timestamp stored in created. Once that time has passed, that HSTS policy will no longer be valid and will eventually be removed from the database.
If you supply your own HSTS database via --hsts-file, be aware that Wget may modify the provided file if any change occurs between the HSTS policies requested by the remote servers and those in the file. When Wget exists, it effectively updates the HSTS database by rewriting the database file with the new entries.
If the supplied file does not exist, Wget will create one. This file will contain the new HSTS entries. If no HSTS entries were generated (no "Strict-Transport-Security" headers were sent by any of the servers) then no file will be created, not even an empty one. This behaviour applies to the default database file (~/.wget-hsts) as well: it will not be created until some server enforces an HSTS policy.
Care is taken not to override possible changes made by other Wget processes at the same time over the HSTS database. Before dumping the updated HSTS entries on the file, Wget will re-read it and merge the changes.
Using a custom HSTS database and/or modifying an existing one is discouraged. For more information about the potential security threats arised from such practice, see section 14 ``Security Considerations'' of RFC 6797, specially section 14.9 ``Creative Manipulation of HSTS Policy Store''.
- Use file as the destination WARC file.
- Use string into as the warcinfo record.
- Set the maximum size of the WARC files to size.
- Write CDX index files.
- Do not store records listed in this CDX file.
- Do not compress WARC files with GZIP.
- Do not calculate SHA1 digests.
- Do not store the log file in a WARC record.
- Specify the location for temporary files created by the WARC writer.
- Turn on recursive retrieving. The default maximum depth is 5.
- -l depth
- Specify recursion maximum depth level depth.
- This option tells Wget to delete every single file it downloads, after having done so. It is useful for pre-fetching popular pages through a proxy, e.g.:
wget -r -nd --delete-after http://whatever.com/~popular/page/
The -r option is to retrieve recursively, and -nd to not create directories.
Note that --delete-after deletes files on the local machine. It does not issue the DELE command to remote FTP sites, for instance. Also note that when --delete-after is specified, --convert-links is ignored, so .orig files are simply not created in the first place.
- After the download is complete, convert the links in the document to make them suitable for local viewing. This affects not only the visible hyperlinks, but any part of the document that links to external content, such as embedded images, links to style sheets, hyperlinks to non-HTML content, etc.
Each link will be changed in one of the two ways:
- The links to files that have been downloaded by Wget will be changed to refer to the file they point to as a relative link.
Example: if the downloaded file /foo/doc.html links to /bar/img.gif, also downloaded, then the link in doc.html will be modified to point to ../bar/img.gif. This kind of transformation works reliably for arbitrary combinations of directories.
- The links to files that have not been downloaded by Wget will be changed to include host name and absolute path of the location they point to.
Example: if the downloaded file /foo/doc.html links to /bar/img.gif (or to ../bar/img.gif), then the link in doc.html will be modified to point to http://hostname/bar/img.gif.
Because of this, local browsing works reliably: if a linked file was downloaded, the link will refer to its local name; if it was not downloaded, the link will refer to its full Internet address rather than presenting a broken link. The fact that the former links are converted to relative links ensures that you can move the downloaded hierarchy to another directory.
Note that only at the end of the download can Wget know which links have been downloaded. Because of that, the work done by -k will be performed at the end of all the downloads.
- This option converts only the filename part of the URLs, leaving the rest of the URLs untouched. This filename part is sometimes referred to as the ``basename'', although we avoid that term here in order not to cause confusion.
It works particularly well in conjunction with --adjust-extension, although this coupling is not enforced. It proves useful to populate Internet caches with files downloaded from different hosts.
Example: if some link points to //foo.com/bar.cgi?xyz with --adjust-extension asserted and its local destination is intended to be ./foo.com/bar.cgi?xyz.css, then the link would be converted to //foo.com/bar.cgi?xyz.css. Note that only the filename part has been modified. The rest of the URL has been left untouched, including the net path ("//") which would otherwise be processed by Wget and converted to the effective scheme (ie. "http://").
- When converting a file, back up the original version with a .orig suffix. Affects the behavior of -N.
- Turn on options suitable for mirroring. This option turns on recursion and time-stamping, sets infinite recursion depth and keeps FTP directory listings. It is currently equivalent to -r -N -l inf --no-remove-listing.
- This option causes Wget to download all the files that are necessary to properly display a given HTML page. This includes such things as inlined images, sounds, and referenced stylesheets.
Ordinarily, when downloading a single HTML page, any requisite documents that may be needed to display it properly are not downloaded. Using -r together with -l can help, but since Wget does not ordinarily distinguish between external and inlined documents, one is generally left with ``leaf documents'' that are missing their requisites.
For instance, say document 1.html contains an "<IMG>" tag referencing 1.gif and an "<A>" tag pointing to external document 2.html. Say that 2.html is similar but that its image is 2.gif and it links to 3.html. Say this continues up to some arbitrarily high number.
If one executes the command:
wget -r -l 2 http://<site>/1.html
then 1.html, 1.gif, 2.html, 2.gif, and 3.html will be downloaded. As you can see, 3.html is without its requisite 3.gif because Wget is simply counting the number of hops (up to 2) away from 1.html in order to determine where to stop the recursion. However, with this command:
wget -r -l 2 -p http://<site>/1.html
all the above files and 3.html's requisite 3.gif will be downloaded. Similarly,
wget -r -l 1 -p http://<site>/1.html
will cause 1.html, 1.gif, 2.html, and 2.gif to be downloaded. One might think that:
wget -r -l 0 -p http://<site>/1.html
would download just 1.html and 1.gif, but unfortunately this is not the case, because -l 0 is equivalent to -l inf---that is, infinite recursion. To download a single HTML page (or a handful of them, all specified on the command-line or in a -i URL input file) and its (or their) requisites, simply leave off -r and -l:
wget -p http://<site>/1.html
Note that Wget will behave as if -r had been specified, but only that single page and its requisites will be downloaded. Links from that page to external documents will not be followed. Actually, to download a single page and all its requisites (even if they exist on separate websites), and make sure the lot displays properly locally, this author likes to use a few options in addition to -p:
wget -E -H -k -K -p http://<site>/<document>
To finish off this topic, it's worth knowing that Wget's idea of an external document link is any URL specified in an "<A>" tag, an "<AREA>" tag, or a "<LINK>" tag other than "<LINK REL="stylesheet">".
- Turn on strict parsing of HTML comments. The default is to terminate comments at the first occurrence of -->.
According to specifications, HTML comments are expressed as SGML declarations. Declaration is special markup that begins with <! and ends with >, such as <!DOCTYPE ...>, that may contain comments between a pair of -- delimiters. HTML comments are ``empty declarations'', SGML declarations without any non-comment text. Therefore, <!--foo--> is a valid comment, and so is <!--one--- --two-->, but <!--1--2--> is not.
On the other hand, most HTML writers don't perceive comments as anything other than text delimited with <!-- and -->, which is not quite the same. For example, something like <!------------> works as a valid comment as long as the number of dashes is a multiple of four (!). If not, the comment technically lasts until the next --, which may be at the other end of the document. Because of this, many popular browsers completely ignore the specification and implement what users have come to expect: comments delimited with <!-- and -->.
Until version 1.9, Wget interpreted comments strictly, which resulted in missing links in many web pages that displayed fine in browsers, but had the misfortune of containing non-compliant comments. Beginning with version 1.9, Wget has joined the ranks of clients that implements ``naive'' comments, terminating each comment at the first occurrence of -->.
If, for whatever reason, you want strict comment parsing, use this option to turn it on.