This file documents the the GNU Wget utility for downloading network
data.
Copyright (C) 1996, 1997, 1998, 2000, 2001 Free Software Foundation,
Inc.
Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation; with the
Invariant Sections being "GNU General Public License" and "GNU Free
Documentation License", with no Front-Cover Texts, and with no
Back-Cover Texts. A copy of the license is included in the section
entitled "GNU Free Documentation License".
Wget 1.8.1
**********
This manual documents version 1.8.1 of GNU Wget, the freely
available utility for network download.
Copyright (C) 1996, 1997, 1998, 2000, 2001 Free Software Foundation,
Inc.
Overview
********
GNU Wget is a free utility for non-interactive download of files from
the Web. It supports HTTP, HTTPS, and FTP protocols, as well as
retrieval through HTTP proxies.
This chapter is a partial overview of Wget's features.
* Wget is non-interactive, meaning that it can work in the
background, while the user is not logged on. This allows you to
start a retrieval and disconnect from the system, letting Wget
finish the work. By contrast, most of the Web browsers require
constant user's presence, which can be a great hindrance when
transferring a lot of data.
* Wget can follow links in HTML pages and create local versions of
remote web sites, fully recreating the directory structure of the
original site. This is sometimes referred to as "recursive
downloading." While doing that, Wget respects the Robot Exclusion
Standard (`/robots.txt'). Wget can be instructed to convert the
links in downloaded HTML files to the local files for offline
viewing.
* File name wildcard matching and recursive mirroring of directories
are available when retrieving via FTP. Wget can read the
time-stamp information given by both HTTP and FTP servers, and
store it locally. Thus Wget can see if the remote file has
changed since last retrieval, and automatically retrieve the new
version if it has. This makes Wget suitable for mirroring of FTP
sites, as well as home pages.
* Wget has been designed for robustness over slow or unstable network
connections; if a download fails due to a network problem, it will
keep retrying until the whole file has been retrieved. If the
server supports regetting, it will instruct the server to continue
the download from where it left off.
* Wget supports proxy servers, which can lighten the network load,
speed up retrieval and provide access behind firewalls. However,
if you are behind a firewall that requires that you use a socks
style gateway, you can get the socks library and build Wget with
support for socks. Wget also supports the passive FTP downloading
as an option.
* Builtin features offer mechanisms to tune which links you wish to
follow (*note Following Links::).
* The retrieval is conveniently traced with printing dots, each dot
representing a fixed amount of data received (1KB by default).
These representations can be customized to your preferences.
* Most of the features are fully configurable, either through
command line options, or via the initialization file `.wgetrc'
(*note Startup File::). Wget allows you to define "global"
startup files (`/usr/local/etc/wgetrc' by default) for site
settings.
* Finally, GNU Wget is free software. This means that everyone may
use it, redistribute it and/or modify it under the terms of the
GNU General Public License, as published by the Free Software
Foundation (*note Copying::).
Invoking
********
By default, Wget is very simple to invoke. The basic syntax is:
wget [OPTION]... [URL]...
Wget will simply download all the URLs specified on the command
line. URL is a "Uniform Resource Locator", as defined below.
However, you may wish to change some of the default parameters of
Wget. You can do it two ways: permanently, adding the appropriate
command to `.wgetrc' (*note Startup File::), or specifying it on the
command line.
URL Format
==========
"URL" is an acronym for Uniform Resource Locator. A uniform
resource locator is a compact string representation for a resource
available via the Internet. Wget recognizes the URL syntax as per
RFC1738. This is the most widely used form (square brackets denote
optional parts):
http://host[:port]/directory/file
ftp://host[:port]/directory/file
You can also encode your username and password within a URL:
ftp://user:password@host/path
http://user:password@host/path
Either USER or PASSWORD, or both, may be left out. If you leave out
either the HTTP username or password, no authentication will be sent.
If you leave out the FTP username, `anonymous' will be used. If you
leave out the FTP password, your email address will be supplied as a
default password.(1)
You can encode unsafe characters in a URL as `%xy', `xy' being the
hexadecimal representation of the character's ASCII value. Some common
unsafe characters include `%' (quoted as `%25'), `:' (quoted as `%3A'),
and `@' (quoted as `%40'). Refer to RFC1738 for a comprehensive list
of unsafe characters.
Wget also supports the `type' feature for FTP URLs. By default, FTP
documents are retrieved in the binary mode (type `i'), which means that
they are downloaded unchanged. Another useful mode is the `a'
("ASCII") mode, which converts the line delimiters between the
different operating systems, and is thus useful for text files. Here
is an example:
ftp://host/directory/file;type=a
Two alternative variants of URL specification are also supported,
because of historical (hysterical?) reasons and their widespreaded use.
FTP-only syntax (supported by `NcFTP'):
host:/dir/file
HTTP-only syntax (introduced by `Netscape'):
host[:port]/dir/file
These two alternative forms are deprecated, and may cease being
supported in the future.
If you do not understand the difference between these notations, or
do not know which one to use, just use the plain ordinary format you use
with your favorite browser, like `Lynx' or `Netscape'.
---------- Footnotes ----------
(1) If you have a `.netrc' file in your home directory, password
will also be searched for there.
Option Syntax
=============
Since Wget uses GNU getopts to process its arguments, every option
has a short form and a long form. 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:
wget -r --tries=10 http://fly.srk.fer.hr/ -o log
The space between the option accepting an argument and the argument
may be omitted. Instead `-o log' you can write `-olog'.
You may put several options that do not require arguments together,
like:
wget -drc URL
This is a complete equivalent of:
wget -d -r -c URL
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':
wget -o log -- -x
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' (*note Wgetrc Syntax::).
wget -X '' -X /~nobody,/~somebody
Basic Startup Options
=====================
`-V'
`--version'
Display the version of Wget.
`-h'
`--help'
Print a help message describing all of Wget's command-line options.
`-b'
`--background'
Go to background immediately after startup. If no output file is
specified via the `-o', output is redirected to `wget-log'.
`-e COMMAND'
`--execute COMMAND'
Execute COMMAND as if it were a part of `.wgetrc' (*note Startup
File::). A command thus invoked will be executed _after_ the
commands in `.wgetrc', thus taking precedence over them.
Logging and Input File Options
==============================
`-o LOGFILE'
`--output-file=LOGFILE'
Log all messages to LOGFILE. The messages are normally reported
to standard error.
`-a LOGFILE'
`--append-output=LOGFILE'
Append to LOGFILE. This is the same as `-o', only it appends to
LOGFILE instead of overwriting the old log file. If LOGFILE does
not exist, a new file is created.
`-d'
`--debug'
Turn on debug output, meaning various information important to the
developers of Wget if it does not work properly. Your system
administrator may have chosen to compile Wget without debug
support, in which case `-d' will not work. Please note that
compiling with debug support is always safe--Wget compiled with
the debug support will _not_ print any debug info unless requested
with `-d'. *Note Reporting Bugs::, for more information on how to
use `-d' for sending bug reports.
`-q'
`--quiet'
Turn off Wget's output.
`-v'
`--verbose'
Turn on verbose output, with all the available data. The default
output is verbose.
`-nv'
`--non-verbose'
Non-verbose output--turn off verbose without being completely quiet
(use `-q' for that), which means that error messages and basic
information still get printed.
`-i FILE'
`--input-file=FILE'
Read URLs from FILE, in which case no URLs need to be on the
command line. If there are URLs both on the command line and in
an input file, those on the command lines will be the first ones to
be retrieved. The FILE need not be an HTML document (but no harm
if it is)--it is enough if the URLs are just listed sequentially.
However, if you specify `--force-html', the document will be
regarded as `html'. In that case you may have problems with
relative links, which you can solve either by adding `<base
href="URL">' to the documents or by specifying `--base=URL' on the
command line.
`-F'
`--force-html'
When input is read from a file, force it to be treated as an HTML
file. This enables you to retrieve relative links from existing
HTML files on your local disk, by adding `<base href="URL">' to
HTML, or using the `--base' command-line option.
`-B URL'
`--base=URL'
When used in conjunction with `-F', prepends URL to relative links
in the file specified by `-i'.
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.
`-t NUMBER'
`--tries=NUMBER'
Set number of retries to NUMBER. Specify 0 or `inf' for infinite
retrying.
`-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 FILE
already exists, it will be overwritten. If the FILE is `-', the
documents will be written to standard output. Including this
option automatically sets the number of tries to 1.
`-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', or `-r', 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. 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', but without `-N' 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', 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 (*note
Time-Stamping::). `-nc' may not be specified at the same time as
`-N'.
Note that when `-nc' is specified, files with the suffixes `.html'
or (yuck) `.htm' will be loaded from the local disk and parsed as
if they had been retrieved from the Web.
`-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.
Beginning with Wget 1.7, if you use `-c' on a non-empty file, and
it turns out that the server does not support continued
downloading, Wget will refuse to start the download from scratch,
which would effectively ruin existing contents. If you really
want the download to start from scratch, remove the file.
Also 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.
`--progress=TYPE'
Select the type of the progress indicator you wish to use. Legal
indicators are "dot" and "bar".
The "dot" indicator is used by default. It traces the retrieval by
printing dots on the screen, each dot representing a fixed amount
of downloaded data.
When using the dotted retrieval, you may also 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 very 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).
Specifying `--progress=bar' will draw a nice ASCII progress bar
graphics (a.k.a "thermometer" display) to indicate retrieval. If
the output is not a TTY, this option will be ignored, and Wget
will revert to the dot indicator. If you want to force the bar
indicator, use `--progress=bar:force'.
`-N'
`--timestamping'
Turn on time-stamping. *Note Time-Stamping::, for details.
`-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. You can use it to check your bookmarks, e.g. with:
wget --spider --force-html -i bookmarks.html
This feature needs much more work for Wget to get close to the
functionality of real WWW spiders.
`-T seconds'
`--timeout=SECONDS'
Set the read timeout to SECONDS seconds. Whenever a network read
is issued, the file descriptor is checked for a timeout, which
could otherwise leave a pending connection (uninterrupted read).
The default timeout is 900 seconds (fifteen minutes). Setting
timeout to 0 will disable checking for timeouts.
Please do not lower the default timeout value with this option
unless you know what you are doing.
`-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.
`--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. Therefore, a value of 10 will actually make Wget wait up
to (1 + 2 + ... + 10) = 55 seconds per file.
Note that this option is turned on by default in the global
`wgetrc' file.
`--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 and 2 * WAIT seconds,
where WAIT was specified using the `-w' or `--wait' options, in
order to mask Wget's presence from such analysis.
A recent 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.
`-Y on/off'
`--proxy=on/off'
Turn proxy support on or off. The proxy is on by default if the
appropriate environmental variable is defined.
`-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 ftp://wuarchive.wustl.edu/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.
Directory Options
=================
`-nd'
`--no-directories'
Do not create a hierarchy of directories when retrieving
recursively. With this option turned on, all files will get saved
to the current directory, without clobbering (if a name shows up
more than once, the filenames will get extensions `.n').
`-x'
`--force-directories'
The opposite of `-nd'--create a hierarchy of directories, even if
one would not have been created otherwise. E.g. `wget -x
http://fly.srk.fer.hr/robots.txt' will save the downloaded file to
`fly.srk.fer.hr/robots.txt'.
`-nH'
`--no-host-directories'
Disable generation of host-prefixed directories. By default,
invoking Wget with `-r http://fly.srk.fer.hr/' will create a
structure of directories beginning with `fly.srk.fer.hr/'. This
option disables such behavior.
`--cut-dirs=NUMBER'
Ignore NUMBER directory components. This is useful for getting a
fine-grained control over the directory where recursive retrieval
will be saved.
Take, for example, the directory at
`ftp://ftp.xemacs.org/pub/xemacs/'. If you retrieve it with `-r',
it will be saved locally under `ftp.xemacs.org/pub/xemacs/'.
While the `-nH' option can remove the `ftp.xemacs.org/' part, you
are still stuck with `pub/xemacs'. This is where `--cut-dirs'
comes in handy; it makes Wget not "see" NUMBER remote directory
components. Here are several examples of how `--cut-dirs' option
works.
No options -> ftp.xemacs.org/pub/xemacs/
-nH -> pub/xemacs/
-nH --cut-dirs=1 -> xemacs/
-nH --cut-dirs=2 -> .
--cut-dirs=1 -> ftp.xemacs.org/xemacs/
...
If you just want to get rid of the directory structure, this
option is similar to a combination of `-nd' and `-P'. However,
unlike `-nd', `--cut-dirs' does not lose with subdirectories--for
instance, with `-nH --cut-dirs=1', a `beta/' subdirectory will be
placed to `xemacs/beta', as one would expect.
`-P PREFIX'
`--directory-prefix=PREFIX'
Set directory prefix to PREFIX. The "directory prefix" is the
directory where all other files and subdirectories will be saved
to, i.e. the top of the retrieval tree. The default is `.' (the
current directory).
HTTP Options
============
`-E'
`--html-extension'
If a file of type `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 the output of CGIs. 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'.
To prevent this re-downloading, you must use `-k' and `-K' so
that the original version of the file will be saved as `X.orig'
(*note Recursive Retrieval Options::).
`--http-user=USER'
`--http-passwd=PASSWORD'
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) or the `digest' authentication
scheme.
Another way to specify username and password is in the URL itself
(*note URL Format::). For more information about security issues
with Wget, *Note Security Considerations::.
`-C on/off'
`--cache=on/off'
When set to off, 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.
`--cookies=on/off'
When set to off, disable the use of cookies. Cookies are a
mechanism for maintaining server-side state. The server sends the
client a cookie using the `Set-Cookie' header, and the client
responds with the same cookie upon further requests. Since
cookies allow the server owners to keep track of visitors and for
sites to exchange this information, some consider them a breach of
privacy. The default is to use cookies; however, _storing_
cookies is not on 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 --cookies=off --header "Cookie: NAME=VALUE"
`--save-cookies FILE'
Save cookies from FILE at the end of session. Cookies whose
expiry time is not specified, or those that have already expired,
are not saved.
`--ignore-length'
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.
`--header=ADDITIONAL-HEADER'
Define an ADDITIONAL-HEADER to be passed to the HTTP servers.
Headers must contain a `:' preceded by one or more non-blank
characters, 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.
`--proxy-user=USER'
`--proxy-passwd=PASSWORD'
Specify the username USER and password PASSWORD for authentication
on a proxy server. Wget will encode them using the `basic'
authentication scheme.
`--referer=URL'
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.
`-s'
`--save-headers'
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'
`--user-agent=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 conceptually this is not such a bad idea, it
has been abused by servers denying information to clients other
than `Mozilla' or 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.
FTP Options
===========
`-nr'
`--dont-remove-listing'
Don't remove the temporary `.listing' files generated by FTP
retrievals. Normally, these files contain the raw directory
listings received from FTP servers. Not removing them can be
useful for debugging purposes, or when you want to be able to
easily check on the contents of remote server directories (e.g. to
verify that a mirror you're running is complete).
Note that even though Wget writes to a known filename for this
file, this is not a security hole in the scenario of a user making
`.listing' a symbolic link to `/etc/passwd' or something and
asking `root' to run Wget in his or her directory. Depending on
the options used, either Wget will refuse to write to `.listing',
making the globbing/recursion/time-stamping operation fail, or the
symbolic link will be deleted and replaced with the actual
`.listing' file, or the listing will be written to a
`.listing.NUMBER' file.
Even though this situation isn't a problem, though, `root' should
never run Wget in a non-trusted user's directory. A user could do
something as simple as linking `index.html' to `/etc/passwd' and
asking `root' to run Wget with `-N' or `-r' so the file will be
overwritten.
`-g on/off'
`--glob=on/off'
Turn FTP globbing on or off. Globbing means you may use the
shell-like special characters ("wildcards"), like `*', `?', `['
and `]' to retrieve more than one file from the same directory at
once, like:
wget ftp://gnjilux.srk.fer.hr/*.msg
By default, globbing will be turned on if the URL contains a
globbing character. This option may be used to turn globbing on
or off permanently.
You may have to quote the URL to protect it from being expanded by
your shell. Globbing makes Wget look for a directory listing,
which is system-specific. This is why it currently works only
with Unix FTP servers (and the ones emulating Unix `ls' output).
`--passive-ftp'
Use the "passive" FTP retrieval scheme, in which the client
initiates the data connection. This is sometimes required for FTP
to work behind firewalls.
`--retr-symlinks'
Usually, when retrieving FTP directories recursively and a symbolic
link is encountered, the linked-to file is not downloaded.
Instead, a matching symbolic link is created on the local
filesystem. The pointed-to file will not be downloaded unless
this recursive retrieval would have encountered it separately and
downloaded it anyway.
When `--retr-symlinks' is specified, however, symbolic links are
traversed and the pointed-to files are retrieved. At this time,
this option does not cause Wget to traverse symlinks to
directories and recurse through them, but in the future it should
be enhanced to do this.
Note that when retrieving a file (not a directory) because it was
specified on the commandline, rather than because it was recursed
to, this option has no effect. Symbolic links are always
traversed in this case.
Recursive Retrieval Options
===========================
`-r'
`--recursive'
Turn on recursive retrieving. *Note Recursive Retrieval::, for
more details.
`-l DEPTH'
`--level=DEPTH'
Specify recursion maximum depth level DEPTH (*note Recursive
Retrieval::). The default maximum depth is 5.
`--delete-after'
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.
`-k'
`--convert-links'
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.
`-K'
`--backup-converted'
When converting a file, back up the original version with a `.orig'
suffix. Affects the behavior of `-N' (*note HTTP Time-Stamping
Internals::).
`-m'
`--mirror'
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 -nr'.
`-p'
`--page-requisites'
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 commandline 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">'.
Recursive Accept/Reject Options
===============================
`-A ACCLIST --accept ACCLIST'
`-R REJLIST --reject REJLIST'
Specify comma-separated lists of file name suffixes or patterns to
accept or reject (*note Types of Files:: for more details).
`-D DOMAIN-LIST'
`--domains=DOMAIN-LIST'
Set domains to be followed. DOMAIN-LIST is a comma-separated list
of domains. Note that it does _not_ turn on `-H'.
`--exclude-domains DOMAIN-LIST'
Specify the domains that are _not_ to be followed. (*note
Spanning Hosts::).
`--follow-ftp'
Follow FTP links from HTML documents. Without this option, Wget
will ignore all the FTP links.
`--follow-tags=LIST'
Wget has an internal table of HTML tag / attribute pairs that it
considers when looking for linked documents during a recursive
retrieval. If a user wants only a subset of those tags to be
considered, however, he or she should be specify such tags in a
comma-separated LIST with this option.
`-G LIST'
`--ignore-tags=LIST'
This is the opposite of the `--follow-tags' option. To skip
certain HTML tags when recursively looking for documents to
download, specify them in a comma-separated LIST.
In the past, the `-G' option was the best bet for downloading a
single page and its requisites, using a commandline like:
wget -Ga,area -H -k -K -r http://SITE/DOCUMENT
However, the author of this option came across a page with tags
like `<LINK REL="home" HREF="/">' and came to the realization that
`-G' was not enough. One can't just tell Wget to ignore `<LINK>',
because then stylesheets will not be downloaded. Now the best bet
for downloading a single page and its requisites is the dedicated
`--page-requisites' option.
`-H'
`--span-hosts'
Enable spanning across hosts when doing recursive retrieving
(*note Spanning Hosts::).
`-L'
`--relative'
Follow relative links only. Useful for retrieving a specific home
page without any distractions, not even those from the same hosts
(*note Relative Links::).
`-I LIST'
`--include-directories=LIST'
Specify a comma-separated list of directories you wish to follow
when downloading (*note Directory-Based Limits:: for more
details.) Elements of LIST may contain wildcards.
`-X LIST'
`--exclude-directories=LIST'
Specify a comma-separated list of directories you wish to exclude
from download (*note Directory-Based Limits:: for more details.)
Elements of LIST may contain wildcards.
`-np'
`--no-parent'
Do not ever ascend to the parent directory when retrieving
recursively. This is a useful option, since it guarantees that
only the files _below_ a certain hierarchy will be downloaded.
*Note Directory-Based Limits::, for more details.
Recursive Retrieval
*******************
GNU Wget is capable of traversing parts of the Web (or a single HTTP
or FTP server), following links and directory structure. We refer to
this as to "recursive retrieving", or "recursion".
With HTTP URLs, Wget retrieves and parses the HTML from the given
URL, documents, retrieving the files the HTML document was referring
to, through markups like `href', or `src'. If the freshly downloaded
file is also of type `text/html', it will be parsed and followed
further.
Recursive retrieval of HTTP and HTML content is "breadth-first".
This means that Wget first downloads the requested HTML document, then
the documents linked from that document, then the documents linked by
them, and so on. In other words, Wget first downloads the documents at
depth 1, then those at depth 2, and so on until the specified maximum
depth.
The maximum "depth" to which the retrieval may descend is specified
with the `-l' option. The default maximum depth is five layers.
When retrieving an FTP URL recursively, Wget will retrieve all the
data from the given directory tree (including the subdirectories up to
the specified depth) on the remote server, creating its mirror image
locally. FTP retrieval is also limited by the `depth' parameter.
Unlike HTTP recursion, FTP recursion is performed depth-first.
By default, Wget will create a local directory tree, corresponding to
the one found on the remote server.
Recursive retrieving can find a number of applications, the most
important of which is mirroring. It is also useful for WWW
presentations, and any other opportunities where slow network
connections should be bypassed by storing the files locally.
You should be warned that recursive downloads can overload the remote
servers. Because of that, many administrators frown upon them and may
ban access from your site if they detect very fast downloads of big
amounts of content. When downloading from Internet servers, consider
using the `-w' option to introduce a delay between accesses to the
server. The download will take a while longer, but the server
administrator will not be alarmed by your rudeness.
Of course, recursive download may cause problems on your machine. If
left to run unchecked, it can easily fill up the disk. If downloading
from local network, it can also take bandwidth on the system, as well as
consume memory and CPU.
Try to specify the criteria that match the kind of download you are
trying to achieve. If you want to download only one page, use
`--page-requisites' without any additional recursion. If you want to
download things under one directory, use `-np' to avoid downloading
things from other directories. If you want to download all the files
from one directory, use `-l 1' to make sure the recursion depth never
exceeds one. *Note Following Links::, for more information about this.
Recursive retrieval should be used with care. Don't say you were not
warned.
Following Links
***************
When retrieving recursively, one does not wish to retrieve loads of
unnecessary data. Most of the time the users bear in mind exactly what
they want to download, and want Wget to follow only specific links.
For example, if you wish to download the music archive from
`fly.srk.fer.hr', you will not want to download all the home pages that
happen to be referenced by an obscure part of the archive.
Wget possesses several mechanisms that allows you to fine-tune which
links it will follow.
Spanning Hosts
==============
Wget's recursive retrieval normally refuses to visit hosts different
than the one you specified on the command line. This is a reasonable
default; without it, every retrieval would have the potential to turn
your Wget into a small version of google.
However, visiting different hosts, or "host spanning," is sometimes
a useful option. Maybe the images are served from a different server.
Maybe you're mirroring a site that consists of pages interlinked between
three servers. Maybe the server has two equivalent names, and the HTML
pages refer to both interchangeably.
Span to any host--`-H'
The `-H' option turns on host spanning, thus allowing Wget's
recursive run to visit any host referenced by a link. Unless
sufficient recursion-limiting criteria are applied depth, these
foreign hosts will typically link to yet more hosts, and so on
until Wget ends up sucking up much more data than you have
intended.
Limit spanning to certain domains--`-D'
The `-D' option allows you to specify the domains that will be
followed, thus limiting the recursion only to the hosts that
belong to these domains. Obviously, this makes sense only in
conjunction with `-H'. A typical example would be downloading the
contents of `www.server.com', but allowing downloads from
`images.server.com', etc.:
wget -rH -Dserver.com http://www.server.com/
You can specify more than one address by separating them with a
comma, e.g. `-Ddomain1.com,domain2.com'.
Keep download off certain domains--`--exclude-domains'
If there are domains you want to exclude specifically, you can do
it with `--exclude-domains', which accepts the same type of
arguments of `-D', but will _exclude_ all the listed domains. For
example, if you want to download all the hosts from `foo.edu'
domain, with the exception of `sunsite.foo.edu', you can do it like
this:
wget -rH -Dfoo.edu --exclude-domains sunsite.foo.edu \
http://www.foo.edu/
Types of Files
==============
When downloading material from the web, you will often want to
restrict the retrieval to only certain file types. For example, if you
are interested in downloading GIFs, you will not be overjoyed to get
loads of PostScript documents, and vice versa.
Wget offers two options to deal with this problem. Each option
description lists a short name, a long name, and the equivalent command
in `.wgetrc'.
`-A ACCLIST'
`--accept ACCLIST'
`accept = ACCLIST'
The argument to `--accept' option is a list of file suffixes or
patterns that Wget will download during recursive retrieval. A
suffix is the ending part of a file, and consists of "normal"
letters, e.g. `gif' or `.jpg'. A matching pattern contains
shell-like wildcards, e.g. `books*' or `zelazny*196[0-9]*'.
So, specifying `wget -A gif,jpg' will make Wget download only the
files ending with `gif' or `jpg', i.e. GIFs and JPEGs. On the
other hand, `wget -A "zelazny*196[0-9]*"' will download only files
beginning with `zelazny' and containing numbers from 1960 to 1969
anywhere within. Look up the manual of your shell for a
description of how pattern matching works.
Of course, any number of suffixes and patterns can be combined
into a comma-separated list, and given as an argument to `-A'.
`-R REJLIST'
`--reject REJLIST'
`reject = REJLIST'
The `--reject' option works the same way as `--accept', only its
logic is the reverse; Wget will download all files _except_ the
ones matching the suffixes (or patterns) in the list.
So, if you want to download a whole page except for the cumbersome
MPEGs and .AU files, you can use `wget -R mpg,mpeg,au'.
Analogously, to download all files except the ones beginning with
`bjork', use `wget -R "bjork*"'. The quotes are to prevent
expansion by the shell.
The `-A' and `-R' options may be combined to achieve even better
fine-tuning of which files to retrieve. E.g. `wget -A "*zelazny*" -R
.ps' will download all the files having `zelazny' as a part of their
name, but _not_ the PostScript files.
Note that these two options do not affect the downloading of HTML
files; Wget must load all the HTMLs to know where to go at
all--recursive retrieval would make no sense otherwise.
Directory-Based Limits
======================
Regardless of other link-following facilities, it is often useful to
place the restriction of what files to retrieve based on the directories
those files are placed in. There can be many reasons for this--the
home pages may be organized in a reasonable directory structure; or some
directories may contain useless information, e.g. `/cgi-bin' or `/dev'
directories.
Wget offers three different options to deal with this requirement.
Each option description lists a short name, a long name, and the
equivalent command in `.wgetrc'.
`-I LIST'
`--include LIST'
`include_directories = LIST'
`-I' option accepts a comma-separated list of directories included
in the retrieval. Any other directories will simply be ignored.
The directories are absolute paths.
So, if you wish to download from `http://host/people/bozo/'
following only links to bozo's colleagues in the `/people'
directory and the bogus scripts in `/cgi-bin', you can specify:
wget -I /people,/cgi-bin http://host/people/bozo/
`-X LIST'
`--exclude LIST'
`exclude_directories = LIST'
`-X' option is exactly the reverse of `-I'--this is a list of
directories _excluded_ from the download. E.g. if you do not want
Wget to download things from `/cgi-bin' directory, specify `-X
/cgi-bin' on the command line.
The same as with `-A'/`-R', these two options can be combined to
get a better fine-tuning of downloading subdirectories. E.g. if
you want to load all the files from `/pub' hierarchy except for
`/pub/worthless', specify `-I/pub -X/pub/worthless'.
`-np'
`--no-parent'
`no_parent = on'
The simplest, and often very useful way of limiting directories is
disallowing retrieval of the links that refer to the hierarchy
"above" than the beginning directory, i.e. disallowing ascent to
the parent directory/directories.
The `--no-parent' option (short `-np') is useful in this case.
Using it guarantees that you will never leave the existing
hierarchy. Supposing you issue Wget with:
wget -r --no-parent http://somehost/~luzer/my-archive/
You may rest assured that none of the references to
`/~his-girls-homepage/' or `/~luzer/all-my-mpegs/' will be
followed. Only the archive you are interested in will be
downloaded. Essentially, `--no-parent' is similar to
`-I/~luzer/my-archive', only it handles redirections in a more
intelligent fashion.
Relative Links
==============
When `-L' is turned on, only the relative links are ever followed.
Relative links are here defined those that do not refer to the web
server root. For example, these links are relative:
<a href="foo.gif">
<a href="foo/bar.gif">
<a href="../foo/bar.gif">
These links are not relative:
<a href="/foo.gif">
<a href="/foo/bar.gif">
<a href="http://www.server.com/foo/bar.gif">
Using this option guarantees that recursive retrieval will not span
hosts, even without `-H'. In simple cases it also allows downloads to
"just work" without having to convert links.
This option is probably not very useful and might be removed in a
future release.
Following FTP Links
===================
The rules for FTP are somewhat specific, as it is necessary for them
to be. FTP links in HTML documents are often included for purposes of
reference, and it is often inconvenient to download them by default.
To have FTP links followed from HTML documents, you need to specify
the `--follow-ftp' option. Having done that, FTP links will span hosts
regardless of `-H' setting. This is logical, as FTP links rarely point
to the same host where the HTTP server resides. For similar reasons,
the `-L' options has no effect on such downloads. On the other hand,
domain acceptance (`-D') and suffix rules (`-A' and `-R') apply
normally.
Also note that followed links to FTP directories will not be
retrieved recursively further.
Time-Stamping
*************
One of the most important aspects of mirroring information from the
Internet is updating your archives.
Downloading the whole archive again and again, just to replace a few
changed files is expensive, both in terms of wasted bandwidth and money,
and the time to do the update. This is why all the mirroring tools
offer the option of incremental updating.
Such an updating mechanism means that the remote server is scanned in
search of "new" files. Only those new files will be downloaded in the
place of the old ones.
A file is considered new if one of these two conditions are met:
1. A file of that name does not already exist locally.
2. A file of that name does exist, but the remote file was modified
more recently than the local file.
To implement this, the program needs to be aware of the time of last
modification of both local and remote files. We call this information
the "time-stamp" of a file.
The time-stamping in GNU Wget is turned on using `--timestamping'
(`-N') option, or through `timestamping = on' directive in `.wgetrc'.
With this option, for each file it intends to download, Wget will check
whether a local file of the same name exists. If it does, and the
remote file is older, Wget will not download it.
If the local file does not exist, or the sizes of the files do not
match, Wget will download the remote file no matter what the time-stamps
say.
Time-Stamping Usage
===================
The usage of time-stamping is simple. Say you would like to
download a file so that it keeps its date of modification.
wget -S http://www.gnu.ai.mit.edu/
A simple `ls -l' shows that the time stamp on the local file equals
the state of the `Last-Modified' header, as returned by the server. As
you can see, the time-stamping info is preserved locally, even without
`-N' (at least for HTTP).
Several days later, you would like Wget to check if the remote file
has changed, and download it if it has.
wget -N http://www.gnu.ai.mit.edu/
Wget will ask the server for the last-modified date. If the local
file has the same timestamp as the server, or a newer one, the remote
file will not be re-fetched. However, if the remote file is more
recent, Wget will proceed to fetch it.
The same goes for FTP. For example:
wget "ftp://ftp.ifi.uio.no/pub/emacs/gnus/*"
(The quotes around that URL are to prevent the shell from trying to
interpret the `*'.)
After download, a local directory listing will show that the
timestamps match those on the remote server. Reissuing the command
with `-N' will make Wget re-fetch _only_ the files that have been
modified since the last download.
If you wished to mirror the GNU archive every week, you would use a
command like the following, weekly:
wget --timestamping -r ftp://ftp.gnu.org/pub/gnu/
Note that time-stamping will only work for files for which the server
gives a timestamp. For HTTP, this depends on getting a `Last-Modified'
header. For FTP, this depends on getting a directory listing with
dates in a format that Wget can parse (*note FTP Time-Stamping
Internals::).
HTTP Time-Stamping Internals
============================
Time-stamping in HTTP is implemented by checking of the
`Last-Modified' header. If you wish to retrieve the file `foo.html'
through HTTP, Wget will check whether `foo.html' exists locally. If it
doesn't, `foo.html' will be retrieved unconditionally.
If the file does exist locally, Wget will first check its local
time-stamp (similar to the way `ls -l' checks it), and then send a
`HEAD' request to the remote server, demanding the information on the
remote file.
The `Last-Modified' header is examined to find which file was
modified more recently (which makes it "newer"). If the remote file is
newer, it will be downloaded; if it is older, Wget will give up.(1)
When `--backup-converted' (`-K') is specified in conjunction with
`-N', server file `X' is compared to local file `X.orig', if extant,
rather than being compared to local file `X', which will always differ
if it's been converted by `--convert-links' (`-k').
Arguably, HTTP time-stamping should be implemented using the
`If-Modified-Since' request.
---------- Footnotes ----------
(1) As an additional check, Wget will look at the `Content-Length'
header, and compare the sizes; if they are not the same, the remote
file will be downloaded no matter what the time-stamp says.
FTP Time-Stamping Internals
===========================
In theory, FTP time-stamping works much the same as HTTP, only FTP
has no headers--time-stamps must be ferreted out of directory listings.
If an FTP download is recursive or uses globbing, Wget will use the
FTP `LIST' command to get a file listing for the directory containing
the desired file(s). It will try to analyze the listing, treating it
like Unix `ls -l' output, extracting the time-stamps. The rest is
exactly the same as for HTTP. Note that when retrieving individual
files from an FTP server without using globbing or recursion, listing
files will not be downloaded (and thus files will not be time-stamped)
unless `-N' is specified.
Assumption that every directory listing is a Unix-style listing may
sound extremely constraining, but in practice it is not, as many
non-Unix FTP servers use the Unixoid listing format because most (all?)
of the clients understand it. Bear in mind that RFC959 defines no
standard way to get a file list, let alone the time-stamps. We can
only hope that a future standard will define this.
Another non-standard solution includes the use of `MDTM' command
that is supported by some FTP servers (including the popular
`wu-ftpd'), which returns the exact time of the specified file. Wget
may support this command in the future.
Startup File
************
Once you know how to change default settings of Wget through command
line arguments, you may wish to make some of those settings permanent.
You can do that in a convenient way by creating the Wget startup
file--`.wgetrc'.
Besides `.wgetrc' is the "main" initialization file, it is
convenient to have a special facility for storing passwords. Thus Wget
reads and interprets the contents of `$HOME/.netrc', if it finds it.
You can find `.netrc' format in your system manuals.
Wget reads `.wgetrc' upon startup, recognizing a limited set of
commands.
Wgetrc Location
===============
When initializing, Wget will look for a "global" startup file,
`/usr/local/etc/wgetrc' by default (or some prefix other than
`/usr/local', if Wget was not installed there) and read commands from
there, if it exists.
Then it will look for the user's file. If the environmental variable
`WGETRC' is set, Wget will try to load that file. Failing that, no
further attempts will be made.
If `WGETRC' is not set, Wget will try to load `$HOME/.wgetrc'.
The fact that user's settings are loaded after the system-wide ones
means that in case of collision user's wgetrc _overrides_ the
system-wide wgetrc (in `/usr/local/etc/wgetrc' by default). Fascist
admins, away!
Wgetrc Syntax
=============
The syntax of a wgetrc command is simple:
variable = value
The "variable" will also be called "command". Valid "values" are
different for different commands.
The commands are case-insensitive and underscore-insensitive. Thus
`DIr__PrefiX' is the same as `dirprefix'. Empty lines, lines beginning
with `#' and lines containing white-space only are discarded.
Commands that expect a comma-separated list will clear the list on an
empty command. So, if you wish to reset the rejection list specified in
global `wgetrc', you can do it with:
reject =
Wgetrc Commands
===============
The complete set of commands is listed below. Legal values are
listed after the `='. Simple Boolean values can be set or unset using
`on' and `off' or `1' and `0'. A fancier kind of Boolean allowed in
some cases is the "lockable Boolean", which may be set to `on', `off',
`always', or `never'. If an option is set to `always' or `never', that
value will be locked in for the duration of the Wget
invocation--commandline options will not override.
Some commands take pseudo-arbitrary values. ADDRESS values can be
hostnames or dotted-quad IP addresses. N can be any positive integer,
or `inf' for infinity, where appropriate. STRING values can be any
non-empty string.
Most of these commands have commandline equivalents (*note
Invoking::), though some of the more obscure or rarely used ones do not.
accept/reject = STRING
Same as `-A'/`-R' (*note Types of Files::).
add_hostdir = on/off
Enable/disable host-prefixed file names. `-nH' disables it.
continue = on/off
If set to on, force continuation of preexistent partially retrieved
files. See `-c' before setting it.
background = on/off
Enable/disable going to background--the same as `-b' (which
enables it).
backup_converted = on/off
Enable/disable saving pre-converted files with the suffix
`.orig'--the same as `-K' (which enables it).
base = STRING
Consider relative URLs in URL input files forced to be interpreted
as HTML as being relative to STRING--the same as `-B'.
bind_address = ADDRESS
Bind to ADDRESS, like the `--bind-address' option.
cache = on/off
When set to off, disallow server-caching. See the `-C' option.
convert links = on/off
Convert non-relative links locally. The same as `-k'.
cookies = on/off
When set to off, disallow cookies. See the `--cookies' option.
load_cookies = FILE
Load cookies from FILE. See `--load-cookies'.
save_cookies = FILE
Save cookies to FILE. See `--save-cookies'.
cut_dirs = N
Ignore N remote directory components.
debug = on/off
Debug mode, same as `-d'.
delete_after = on/off
Delete after download--the same as `--delete-after'.
dir_prefix = STRING
Top of directory tree--the same as `-P'.
dirstruct = on/off
Turning dirstruct on or off--the same as `-x' or `-nd',
respectively.
domains = STRING
Same as `-D' (*note Spanning Hosts::).
dot_bytes = N
Specify the number of bytes "contained" in a dot, as seen
throughout the retrieval (1024 by default). You can postfix the
value with `k' or `m', representing kilobytes and megabytes,
respectively. With dot settings you can tailor the dot retrieval
to suit your needs, or you can use the predefined "styles" (*note
Download Options::).
dots_in_line = N
Specify the number of dots that will be printed in each line
throughout the retrieval (50 by default).
dot_spacing = N
Specify the number of dots in a single cluster (10 by default).
exclude_directories = STRING
Specify a comma-separated list of directories you wish to exclude
from download--the same as `-X' (*note Directory-Based Limits::).
exclude_domains = STRING
Same as `--exclude-domains' (*note Spanning Hosts::).
follow_ftp = on/off
Follow FTP links from HTML documents--the same as `--follow-ftp'.
follow_tags = STRING
Only follow certain HTML tags when doing a recursive retrieval,
just like `--follow-tags'.
force_html = on/off
If set to on, force the input filename to be regarded as an HTML
document--the same as `-F'.
ftp_proxy = STRING
Use STRING as FTP proxy, instead of the one specified in
environment.
glob = on/off
Turn globbing on/off--the same as `-g'.
header = STRING
Define an additional header, like `--header'.
html_extension = on/off
Add a `.html' extension to `text/html' files without it, like `-E'.
http_passwd = STRING
Set HTTP password.
http_proxy = STRING
Use STRING as HTTP proxy, instead of the one specified in
environment.
http_user = STRING
Set HTTP user to STRING.
ignore_length = on/off
When set to on, ignore `Content-Length' header; the same as
`--ignore-length'.
ignore_tags = STRING
Ignore certain HTML tags when doing a recursive retrieval, just
like `-G' / `--ignore-tags'.
include_directories = STRING
Specify a comma-separated list of directories you wish to follow
when downloading--the same as `-I'.
input = STRING
Read the URLs from STRING, like `-i'.
kill_longer = on/off
Consider data longer than specified in content-length header as
invalid (and retry getting it). The default behaviour is to save
as much data as there is, provided there is more than or equal to
the value in `Content-Length'.
logfile = STRING
Set logfile--the same as `-o'.
login = STRING
Your user name on the remote machine, for FTP. Defaults to
`anonymous'.
mirror = on/off
Turn mirroring on/off. The same as `-m'.
netrc = on/off
Turn reading netrc on or off.
noclobber = on/off
Same as `-nc'.
no_parent = on/off
Disallow retrieving outside the directory hierarchy, like
`--no-parent' (*note Directory-Based Limits::).
no_proxy = STRING
Use STRING as the comma-separated list of domains to avoid in
proxy loading, instead of the one specified in environment.
output_document = STRING
Set the output filename--the same as `-O'.
page_requisites = on/off
Download all ancillary documents necessary for a single HTML page
to display properly--the same as `-p'.
passive_ftp = on/off/always/never
Set passive FTP--the same as `--passive-ftp'. Some scripts and
`.pm' (Perl module) files download files using `wget
--passive-ftp'. If your firewall does not allow this, you can set
`passive_ftp = never' to override the commandline.
passwd = STRING
Set your FTP password to PASSWORD. Without this setting, the
password defaults to `username@hostname.domainname'.
progress = STRING
Set the type of the progress indicator. Legal types are "dot" and
"bar".
proxy_user = STRING
Set proxy authentication user name to STRING, like `--proxy-user'.
proxy_passwd = STRING
Set proxy authentication password to STRING, like `--proxy-passwd'.
referer = STRING
Set HTTP `Referer:' header just like `--referer'. (Note it was
the folks who wrote the HTTP spec who got the spelling of
"referrer" wrong.)
quiet = on/off
Quiet mode--the same as `-q'.
quota = QUOTA
Specify the download quota, which is useful to put in the global
`wgetrc'. When download quota is specified, Wget will stop
retrieving after the download sum has become greater than quota.
The quota can be specified in bytes (default), kbytes `k'
appended) or mbytes (`m' appended). Thus `quota = 5m' will set
the quota to 5 mbytes. Note that the user's startup file
overrides system settings.
reclevel = N
Recursion level--the same as `-l'.
recursive = on/off
Recursive on/off--the same as `-r'.
relative_only = on/off
Follow only relative links--the same as `-L' (*note Relative
Links::).
remove_listing = on/off
If set to on, remove FTP listings downloaded by Wget. Setting it
to off is the same as `-nr'.
retr_symlinks = on/off
When set to on, retrieve symbolic links as if they were plain
files; the same as `--retr-symlinks'.
robots = on/off
Use (or not) `/robots.txt' file (*note Robots::). Be sure to know
what you are doing before changing the default (which is `on').
server_response = on/off
Choose whether or not to print the HTTP and FTP server
responses--the same as `-S'.
span_hosts = on/off
Same as `-H'.
timeout = N
Set timeout value--the same as `-T'.
timestamping = on/off
Turn timestamping on/off. The same as `-N' (*note
Time-Stamping::).
tries = N
Set number of retries per URL--the same as `-t'.
use_proxy = on/off
Turn proxy support on/off. The same as `-Y'.
verbose = on/off
Turn verbose on/off--the same as `-v'/`-nv'.
wait = N
Wait N seconds between retrievals--the same as `-w'.
waitretry = N
Wait up to N seconds between retries of failed retrievals
only--the same as `--waitretry'. Note that this is turned on by
default in the global `wgetrc'.
randomwait = on/off
Turn random between-request wait times on or off. The same as
`--random-wait'.
Sample Wgetrc
=============
This is the sample initialization file, as given in the distribution.
It is divided in two section--one for global usage (suitable for global
startup file), and one for local usage (suitable for `$HOME/.wgetrc').
Be careful about the things you change.
Note that almost all the lines are commented out. For a command to
have any effect, you must remove the `#' character at the beginning of
its line.
###
### Sample Wget initialization file .wgetrc
###
## You can use this file to change the default behaviour of wget or to
## avoid having to type many many command-line options. This file does
## not contain a comprehensive list of commands -- look at the manual
## to find out what you can put into this file.
##
## Wget initialization file can reside in /usr/local/etc/wgetrc
## (global, for all users) or $HOME/.wgetrc (for a single user).
##
## To use the settings in this file, you will have to uncomment them,
## as well as change them, in most cases, as the values on the
## commented-out lines are the default values (e.g. "off").
##
## Global settings (useful for setting up in /usr/local/etc/wgetrc).
## Think well before you change them, since they may reduce wget's
## functionality, and make it behave contrary to the documentation:
##
# You can set retrieve quota for beginners by specifying a value
# optionally followed by 'K' (kilobytes) or 'M' (megabytes). The
# default quota is unlimited.
#quota = inf
# You can lower (or raise) the default number of retries when
# downloading a file (default is 20).
#tries = 20
# Lowering the maximum depth of the recursive retrieval is handy to
# prevent newbies from going too "deep" when they unwittingly start
# the recursive retrieval. The default is 5.
#reclevel = 5
# Many sites are behind firewalls that do not allow initiation of
# connections from the outside. On these sites you have to use the
# `passive' feature of FTP. If you are behind such a firewall, you
# can turn this on to make Wget use passive FTP by default.
#passive_ftp = off
# The "wait" command below makes Wget wait between every connection.
# If, instead, you want Wget to wait only between retries of failed
# downloads, set waitretry to maximum number of seconds to wait (Wget
# will use "linear backoff", waiting 1 second after the first failure
# on a file, 2 seconds after the second failure, etc. up to this max).
waitretry = 10
##
## Local settings (for a user to set in his $HOME/.wgetrc). It is
## *highly* undesirable to put these settings in the global file, since
## they are potentially dangerous to "normal" users.
##
## Even when setting up your own ~/.wgetrc, you should know what you
## are doing before doing so.
##
# Set this to on to use timestamping by default:
#timestamping = off
# It is a good idea to make Wget send your email address in a `From:'
# header with your request (so that server administrators can contact
# you in case of errors). Wget does *not* send `From:' by default.
#header = From: Your Name <username@site.domain>
# You can set up other headers, like Accept-Language. Accept-Language
# is *not* sent by default.
#header = Accept-Language: en
# You can set the default proxies for Wget to use for http and ftp.
# They will override the value in the environment.
#http_proxy = http://proxy.yoyodyne.com:18023/
#ftp_proxy = http://proxy.yoyodyne.com:18023/
# If you do not want to use proxy at all, set this to off.
#use_proxy = on
# You can customize the retrieval outlook. Valid options are default,
# binary, mega and micro.
#dot_style = default
# Setting this to off makes Wget not download /robots.txt. Be sure to
# know *exactly* what /robots.txt is and how it is used before changing
# the default!
#robots = on
# It can be useful to make Wget wait between connections. Set this to
# the number of seconds you want Wget to wait.
#wait = 0
# You can force creating directory structure, even if a single is being
# retrieved, by setting this to on.
#dirstruct = off
# You can turn on recursive retrieving by default (don't do this if
# you are not sure you know what it means) by setting this to on.
#recursive = off
# To always back up file X as X.orig before converting its links (due
# to -k / --convert-links / convert_links = on having been specified),
# set this variable to on:
#backup_converted = off
# To have Wget follow FTP links from HTML files by default, set this
# to on:
#follow_ftp = off
Examples
********
The examples are divided into three sections loosely based on their
complexity.
Simple Usage
============
* Say you want to download a URL. Just type:
wget http://fly.srk.fer.hr/
* But what will happen if the connection is slow, and the file is
lengthy? The connection will probably fail before the whole file
is retrieved, more than once. In this case, Wget will try getting
the file until it either gets the whole of it, or exceeds the
default number of retries (this being 20). It is easy to change
the number of tries to 45, to insure that the whole file will
arrive safely:
wget --tries=45 http://fly.srk.fer.hr/jpg/flyweb.jpg
* Now let's leave Wget to work in the background, and write its
progress to log file `log'. It is tiring to type `--tries', so we
shall use `-t'.
wget -t 45 -o log http://fly.srk.fer.hr/jpg/flyweb.jpg &
The ampersand at the end of the line makes sure that Wget works in
the background. To unlimit the number of retries, use `-t inf'.
* The usage of FTP is as simple. Wget will take care of login and
password.
wget ftp://gnjilux.srk.fer.hr/welcome.msg
* If you specify a directory, Wget will retrieve the directory
listing, parse it and convert it to HTML. Try:
wget ftp://prep.ai.mit.edu/pub/gnu/
links index.html
Advanced Usage
==============
* You have a file that contains the URLs you want to download? Use
the `-i' switch:
wget -i FILE
If you specify `-' as file name, the URLs will be read from
standard input.
* Create a five levels deep mirror image of the GNU web site, with
the same directory structure the original has, with only one try
per document, saving the log of the activities to `gnulog':
wget -r http://www.gnu.org/ -o gnulog
* The same as the above, but convert the links in the HTML files to
point to local files, so you can view the documents off-line:
wget --convert-links -r http://www.gnu.org/ -o gnulog
* Retrieve only one HTML page, but make sure that all the elements
needed for the page to be displayed, such as inline images and
external style sheets, are also downloaded. Also make sure the
downloaded page references the downloaded links.
wget -p --convert-links http://www.server.com/dir/page.html
The HTML page will be saved to `www.server.com/dir/page.html', and
the images, stylesheets, etc., somewhere under `www.server.com/',
depending on where they were on the remote server.
* The same as the above, but without the `www.server.com/' directory.
In fact, I don't want to have all those random server directories
anyway--just save _all_ those files under a `download/'
subdirectory of the current directory.
wget -p --convert-links -nH -nd -Pdownload \
http://www.server.com/dir/page.html
* Retrieve the index.html of `www.lycos.com', showing the original
server headers:
wget -S http://www.lycos.com/
* Save the server headers with the file, perhaps for post-processing.
wget -s http://www.lycos.com/
more index.html
* Retrieve the first two levels of `wuarchive.wustl.edu', saving them
to `/tmp'.
wget -r -l2 -P/tmp ftp://wuarchive.wustl.edu/
* You want to download all the GIFs from a directory on an HTTP
server. You tried `wget http://www.server.com/dir/*.gif', but that
didn't work because HTTP retrieval does not support globbing. In
that case, use:
wget -r -l1 --no-parent -A.gif http://www.server.com/dir/
More verbose, but the effect is the same. `-r -l1' means to
retrieve recursively (*note Recursive Retrieval::), with maximum
depth of 1. `--no-parent' means that references to the parent
directory are ignored (*note Directory-Based Limits::), and
`-A.gif' means to download only the GIF files. `-A "*.gif"' would
have worked too.
* Suppose you were in the middle of downloading, when Wget was
interrupted. Now you do not want to clobber the files already
present. It would be:
wget -nc -r http://www.gnu.org/
* If you want to encode your own username and password to HTTP or
FTP, use the appropriate URL syntax (*note URL Format::).
wget ftp://hniksic:mypassword@unix.server.com/.emacs
* You would like the output documents to go to standard output
instead of to files?
wget -O - http://jagor.srce.hr/ http://www.srce.hr/
You can also combine the two options and make pipelines to
retrieve the documents from remote hotlists:
wget -O - http://cool.list.com/ | wget --force-html -i -
Very Advanced Usage
===================
* If you wish Wget to keep a mirror of a page (or FTP
subdirectories), use `--mirror' (`-m'), which is the shorthand for
`-r -l inf -N'. You can put Wget in the crontab file asking it to
recheck a site each Sunday:
crontab
0 0 * * 0 wget --mirror http://www.gnu.org/ -o /home/me/weeklog
* In addition to the above, you want the links to be converted for
local viewing. But, after having read this manual, you know that
link conversion doesn't play well with timestamping, so you also
want Wget to back up the original HTML files before the
conversion. Wget invocation would look like this:
wget --mirror --convert-links --backup-converted \
http://www.gnu.org/ -o /home/me/weeklog
* But you've also noticed that local viewing doesn't work all that
well when HTML files are saved under extensions other than `.html',
perhaps because they were served as `index.cgi'. So you'd like
Wget to rename all the files served with content-type `text/html'
to `NAME.html'.
wget --mirror --convert-links --backup-converted \
--html-extension -o /home/me/weeklog \
http://www.gnu.org/
Or, with less typing:
wget -m -k -K -E http://www.gnu.org/ -o /home/me/weeklog
Various
*******
This chapter contains all the stuff that could not fit anywhere else.
Proxies
=======
"Proxies" are special-purpose HTTP servers designed to transfer data
from remote servers to local clients. One typical use of proxies is
lightening network load for users behind a slow connection. This is
achieved by channeling all HTTP and FTP requests through the proxy
which caches the transferred data. When a cached resource is requested
again, proxy will return the data from cache. Another use for proxies
is for companies that separate (for security reasons) their internal
networks from the rest of Internet. In order to obtain information
from the Web, their users connect and retrieve remote data using an
authorized proxy.
Wget supports proxies for both HTTP and FTP retrievals. The
standard way to specify proxy location, which Wget recognizes, is using
the following environment variables:
`http_proxy'
This variable should contain the URL of the proxy for HTTP
connections.
`ftp_proxy'
This variable should contain the URL of the proxy for FTP
connections. It is quite common that HTTP_PROXY and FTP_PROXY are
set to the same URL.
`no_proxy'
This variable should contain a comma-separated list of domain
extensions proxy should _not_ be used for. For instance, if the
value of `no_proxy' is `.mit.edu', proxy will not be used to
retrieve documents from MIT.
In addition to the environment variables, proxy location and settings
may be specified from within Wget itself.
`-Y on/off'
`--proxy=on/off'
`proxy = on/off'
This option may be used to turn the proxy support on or off. Proxy
support is on by default, provided that the appropriate environment
variables are set.
`http_proxy = URL'
`ftp_proxy = URL'
`no_proxy = STRING'
These startup file variables allow you to override the proxy
settings specified by the environment.
Some proxy servers require authorization to enable you to use them.
The authorization consists of "username" and "password", which must be
sent by Wget. As with HTTP authorization, several authentication
schemes exist. For proxy authorization only the `Basic' authentication
scheme is currently implemented.
You may specify your username and password either through the proxy
URL or through the command-line options. Assuming that the company's
proxy is located at `proxy.company.com' at port 8001, a proxy URL
location containing authorization data might look like this:
http://hniksic:mypassword@proxy.company.com:8001/
Alternatively, you may use the `proxy-user' and `proxy-password'
options, and the equivalent `.wgetrc' settings `proxy_user' and
`proxy_passwd' to set the proxy username and password.
Distribution
============
Like all GNU utilities, the latest version of Wget can be found at
the master GNU archive site prep.ai.mit.edu, and its mirrors. For
example, Wget 1.8.1 can be found at
<ftp://prep.ai.mit.edu/gnu/wget/wget-1.8.1.tar.gz>
Mailing List
============
Wget has its own mailing list at <wget@sunsite.dk>, thanks to
Karsten Thygesen. The mailing list is for discussion of Wget features
and web, reporting Wget bugs (those that you think may be of interest
to the public) and mailing announcements. You are welcome to
subscribe. The more people on the list, the better!
To subscribe, send mail to <wget-subscribe@sunsite.dk>. the magic
word `subscribe' in the subject line. Unsubscribe by mailing to
<wget-unsubscribe@sunsite.dk>.
The mailing list is archived at <http://fly.srk.fer.hr/archive/wget>.
Alternative archive is available at
<http://www.mail-archive.com/wget%40sunsite.auc.dk/>.
Reporting Bugs
==============
You are welcome to send bug reports about GNU Wget to
<bug-wget@gnu.org>.
Before actually submitting a bug report, please try to follow a few
simple guidelines.
1. Please try to ascertain that the behaviour you see really is a
bug. If Wget crashes, it's a bug. If Wget does not behave as
documented, it's a bug. If things work strange, but you are not
sure about the way they are supposed to work, it might well be a
bug.
2. Try to repeat the bug in as simple circumstances as possible.
E.g. if Wget crashes while downloading `wget -rl0 -kKE -t5 -Y0
http://yoyodyne.com -o /tmp/log', you should try to see if the
crash is repeatable, and if will occur with a simpler set of
options. You might even try to start the download at the page
where the crash occurred to see if that page somehow triggered the
crash.
Also, while I will probably be interested to know the contents of
your `.wgetrc' file, just dumping it into the debug message is
probably a bad idea. Instead, you should first try to see if the
bug repeats with `.wgetrc' moved out of the way. Only if it turns
out that `.wgetrc' settings affect the bug, mail me the relevant
parts of the file.
3. Please start Wget with `-d' option and send the log (or the
relevant parts of it). If Wget was compiled without debug support,
recompile it. It is _much_ easier to trace bugs with debug support
on.
4. If Wget has crashed, try to run it in a debugger, e.g. `gdb `which
wget` core' and type `where' to get the backtrace.
Portability
===========
Since Wget uses GNU Autoconf for building and configuring, and avoids
using "special" ultra-mega-cool features of any particular Unix, it
should compile (and work) on all common Unix flavors.
Various Wget versions have been compiled and tested under many kinds
of Unix systems, including Solaris, Linux, SunOS, OSF (aka Digital
Unix), Ultrix, *BSD, IRIX, and others; refer to the file `MACHINES' in
the distribution directory for a comprehensive list. If you compile it
on an architecture not listed there, please let me know so I can update
it.
Wget should also compile on the other Unix systems, not listed in
`MACHINES'. If it doesn't, please let me know.
Thanks to kind contributors, this version of Wget compiles and works
on Microsoft Windows 95 and Windows NT platforms. It has been compiled
successfully using MS Visual C++ 4.0, Watcom, and Borland C compilers,
with Winsock as networking software. Naturally, it is crippled of some
features available on Unix, but it should work as a substitute for
people stuck with Windows. Note that the Windows port is *neither
tested nor maintained* by me--all questions and problems should be
reported to Wget mailing list at <wget@sunsite.dk> where the
maintainers will look at them.
Signals
=======
Since the purpose of Wget is background work, it catches the hangup
signal (`SIGHUP') and ignores it. If the output was on standard
output, it will be redirected to a file named `wget-log'. Otherwise,
`SIGHUP' is ignored. This is convenient when you wish to redirect the
output of Wget after having started it.
$ wget http://www.ifi.uio.no/~larsi/gnus.tar.gz &
$ kill -HUP %% # Redirect the output to wget-log
Other than that, Wget will not try to interfere with signals in any
way. `C-c', `kill -TERM' and `kill -KILL' should kill it alike.
Appendices
**********
This chapter contains some references I consider useful.
Robots
======
It is extremely easy to make Wget wander aimlessly around a web site,
sucking all the available data in progress. `wget -r SITE', and you're
set. Great? Not for the server admin.
While Wget is retrieving static pages, there's not much of a problem.
But for Wget, there is no real difference between a static page and the
most demanding CGI. For instance, a site I know has a section handled
by an, uh, "bitchin'" CGI script that converts all the Info files to
HTML. The script can and does bring the machine to its knees without
providing anything useful to the downloader.
For such and similar cases various robot exclusion schemes have been
devised as a means for the server administrators and document authors to
protect chosen portions of their sites from the wandering of robots.
The more popular mechanism is the "Robots Exclusion Standard", or
RES, written by Martijn Koster et al. in 1994. It specifies the format
of a text file containing directives that instruct the robots which URL
paths to avoid. To be found by the robots, the specifications must be
placed in `/robots.txt' in the server root, which the robots are
supposed to download and parse.
Wget supports RES when downloading recursively. So, when you issue:
wget -r http://www.server.com/
First the index of `www.server.com' will be downloaded. If Wget
finds that it wants to download more documents from that server, it will
request `http://www.server.com/robots.txt' and, if found, use it for
further downloads. `robots.txt' is loaded only once per each server.
Until version 1.8, Wget supported the first version of the standard,
written by Martijn Koster in 1994 and available at
<http://www.robotstxt.org/wc/norobots.html>. As of version 1.8, Wget
has supported the additional directives specified in the internet draft
`<draft-koster-robots-00.txt>' titled "A Method for Web Robots
Control". The draft, which has as far as I know never made to an RFC,
is available at <http://www.robotstxt.org/wc/norobots-rfc.txt>.
This manual no longer includes the text of the Robot Exclusion
Standard.
The second, less known mechanism, enables the author of an individual
document to specify whether they want the links from the file to be
followed by a robot. This is achieved using the `META' tag, like this:
<meta name="robots" content="nofollow">
This is explained in some detail at
<http://www.robotstxt.org/wc/meta-user.html>. Wget supports this
method of robot exclusion in addition to the usual `/robots.txt'
exclusion.
Security Considerations
=======================
When using Wget, you must be aware that it sends unencrypted
passwords through the network, which may present a security problem.
Here are the main issues, and some solutions.
1. The passwords on the command line are visible using `ps'. If this
is a problem, avoid putting passwords from the command line--e.g.
you can use `.netrc' for this.
2. Using the insecure "basic" authentication scheme, unencrypted
passwords are transmitted through the network routers and gateways.
3. The FTP passwords are also in no way encrypted. There is no good
solution for this at the moment.
4. Although the "normal" output of Wget tries to hide the passwords,
debugging logs show them, in all forms. This problem is avoided by
being careful when you send debug logs (yes, even when you send
them to me).
Contributors
============
GNU Wget was written by Hrvoje Niksic <hniksic@arsdigita.com>.
However, its development could never have gone as far as it has, were it
not for the help of many people, either with bug reports, feature
proposals, patches, or letters saying "Thanks!".
Special thanks goes to the following people (no particular order):
* Karsten Thygesen--donated system resources such as the mailing
list, web space, and FTP space, along with a lot of time to make
these actually work.
* Shawn McHorse--bug reports and patches.
* Kaveh R. Ghazi--on-the-fly `ansi2knr'-ization. Lots of
portability fixes.
* Gordon Matzigkeit--`.netrc' support.
* Zlatko Calusic, Tomislav Vujec and Drazen Kacar--feature
suggestions and "philosophical" discussions.
* Darko Budor--initial port to Windows.
* Antonio Rosella--help and suggestions, plus the Italian
translation.
* Tomislav Petrovic, Mario Mikocevic--many bug reports and
suggestions.
* Francois Pinard--many thorough bug reports and discussions.
* Karl Eichwalder--lots of help with internationalization and other
things.
* Junio Hamano--donated support for Opie and HTTP `Digest'
authentication.
* The people who provided donations for development, including Brian
Gough.
The following people have provided patches, bug/build reports, useful
suggestions, beta testing services, fan mail and all the other things
that make maintenance so much fun:
Ian Abbott Tim Adam, Adrian Aichner, Martin Baehr, Dieter Baron,
Roger Beeman, Dan Berger, T. Bharath, Paul Bludov, Daniel Bodea, Mark
Boyns, John Burden, Wanderlei Cavassin, Gilles Cedoc, Tim Charron, Noel
Cragg, Kristijan Conkas, John Daily, Andrew Davison, Andrew Deryabin,
Ulrich Drepper, Marc Duponcheel, Damir Dzeko, Alan Eldridge, Aleksandar
Erkalovic, Andy Eskilsson, Christian Fraenkel, Masashi Fujita, Howard
Gayle, Marcel Gerrits, Lemble Gregory, Hans Grobler, Mathieu Guillaume,
Dan Harkless, Herold Heiko, Jochen Hein, Karl Heuer, HIROSE Masaaki,
Gregor Hoffleit, Erik Magnus Hulthen, Richard Huveneers, Jonas Jensen,
Simon Josefsson, Mario Juric, Hack Kampbjorn, Const Kaplinsky, Goran
Kezunovic, Robert Kleine, KOJIMA Haime, Fila Kolodny, Alexander
Kourakos, Martin Kraemer, Simos KSenitellis, Hrvoje Lacko, Daniel S.
Lewart, Nicolas Lichtmeier, Dave Love, Alexander V. Lukyanov, Jordan
Mendelson, Lin Zhe Min, Tim Mooney, Simon Munton, Charlie Negyesi, R.
K. Owen, Andrew Pollock, Steve Pothier, Jan Prikryl, Marin Purgar,
Csaba Raduly, Keith Refson, Tyler Riddle, Tobias Ringstrom, Juan Jose
Rodrigues, Edward J. Sabol, Heinz Salzmann, Robert Schmidt, Andreas
Schwab, Chris Seawood, Toomas Soome, Tage Stabell-Kulo, Sven
Sternberger, Markus Strasser, John Summerfield, Szakacsits Szabolcs,
Mike Thomas, Philipp Thomas, Dave Turner, Russell Vincent, Charles G
Waldman, Douglas E. Wegscheid, Jasmin Zainul, Bojan Zdrnja, Kristijan
Zimmer.
Apologies to all who I accidentally left out, and many thanks to all
the subscribers of the Wget mailing list.
Copying
*******
GNU Wget is licensed under the GNU GPL, which makes it "free
software".
Please note that "free" in "free software" refers to liberty, not
price. As some GNU project advocates like to point out, think of "free
speech" rather than "free beer". The exact and legally binding
distribution terms are spelled out below; in short, you have the right
(freedom) to run and change Wget and distribute it to other people, and
even--if you want--charge money for doing either. The important
restriction is that you have to grant your recipients the same rights
and impose the same restrictions.
This method of licensing software is also known as "open source"
because, among other things, it makes sure that all recipients will
receive the source code along with the program, and be able to improve
it. The GNU project prefers the term "free software" for reasons
outlined at
<http://www.gnu.org/philosophy/free-software-for-freedom.html>.
The exact license terms are defined by this paragraph and the GNU
General Public License it refers to:
GNU Wget 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.
GNU Wget 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.
A copy of the GNU General Public License is included as part of
this manual; if you did not receive it, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
In addition to this, this manual is free in the same sense:
Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License,
Version 1.1 or any later version published by the Free Software
Foundation; with the Invariant Sections being "GNU General Public
License" and "GNU Free Documentation License", with no Front-Cover
Texts, and with no Back-Cover Texts. A copy of the license is
included in the section entitled "GNU Free Documentation License".
The full texts of the GNU General Public License and of the GNU Free
Documentation License are available below.
GNU General Public License
==========================
Version 2, June 1991
Copyright (C) 1989, 1991 Free Software Foundation, Inc.
675 Mass Ave, Cambridge, MA 02139, USA
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
Preamble
========
The licenses for most software are designed to take away your
freedom to share and change it. By contrast, the GNU General Public
License is intended to guarantee your freedom to share and change free
software--to make sure the software is free for all its users. This
General Public License applies to most of the Free Software
Foundation's software and to any other program whose authors commit to
using it. (Some other Free Software Foundation software is covered by
the GNU Library General Public License instead.) You can apply it to
your programs, too.
When we speak of free software, we are referring to freedom, not
price. Our General Public Licenses are designed to make sure that you
have the freedom to distribute copies of free software (and charge for
this service if you wish), that you receive source code or can get it
if you want it, that you can change the software or use pieces of it in
new free programs; and that you know you can do these things.
To protect your rights, we need to make restrictions that forbid
anyone to deny you these rights or to ask you to surrender the rights.
These restrictions translate to certain responsibilities for you if you
distribute copies of the software, or if you modify it.
For example, if you distribute copies of such a program, whether
gratis or for a fee, you must give the recipients all the rights that
you have. You must make sure that they, too, receive or can get the
source code. And you must show them these terms so they know their
rights.
We protect your rights with two steps: (1) copyright the software,
and (2) offer you this license which gives you legal permission to copy,
distribute and/or modify the software.
Also, for each author's protection and ours, we want to make certain
that everyone understands that there is no warranty for this free
software. If the software is modified by someone else and passed on, we
want its recipients to know that what they have is not the original, so
that any problems introduced by others will not reflect on the original
authors' reputations.
Finally, any free program is threatened constantly by software
patents. We wish to avoid the danger that redistributors of a free
program will individually obtain patent licenses, in effect making the
program proprietary. To prevent this, we have made it clear that any
patent must be licensed for everyone's free use or not licensed at all.
The precise terms and conditions for copying, distribution and
modification follow.
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
1. This License applies to any program or other work which contains a
notice placed by the copyright holder saying it may be distributed
under the terms of this General Public License. The "Program",
below, refers to any such program or work, and a "work based on
the Program" means either the Program or any derivative work under
copyright law: that is to say, a work containing the Program or a
portion of it, either verbatim or with modifications and/or
translated into another language. (Hereinafter, translation is
included without limitation in the term "modification".) Each
licensee is addressed as "you".
Activities other than copying, distribution and modification are
not covered by this License; they are outside its scope. The act
of running the Program is not restricted, and the output from the
Program is covered only if its contents constitute a work based on
the Program (independent of having been made by running the
Program). Whether that is true depends on what the Program does.
2. You may copy and distribute verbatim copies of the Program's
source code as you receive it, in any medium, provided that you
conspicuously and appropriately publish on each copy an appropriate
copyright notice and disclaimer of warranty; keep intact all the
notices that refer to this License and to the absence of any
warranty; and give any other recipients of the Program a copy of
this License along with the Program.
You may charge a fee for the physical act of transferring a copy,
and you may at your option offer warranty protection in exchange
for a fee.
3. You may modify your copy or copies of the Program or any portion
of it, thus forming a work based on the Program, and copy and
distribute such modifications or work under the terms of Section 1
above, provided that you also meet all of these conditions:
a. You must cause the modified files to carry prominent notices
stating that you changed the files and the date of any change.
b. You must cause any work that you distribute or publish, that
in whole or in part contains or is derived from the Program
or any part thereof, to be licensed as a whole at no charge
to all third parties under the terms of this License.
c. If the modified program normally reads commands interactively
when run, you must cause it, when started running for such
interactive use in the most ordinary way, to print or display
an announcement including an appropriate copyright notice and
a notice that there is no warranty (or else, saying that you
provide a warranty) and that users may redistribute the
program under these conditions, and telling the user how to
view a copy of this License. (Exception: if the Program
itself is interactive but does not normally print such an
announcement, your work based on the Program is not required
to print an announcement.)
These requirements apply to the modified work as a whole. If
identifiable sections of that work are not derived from the
Program, and can be reasonably considered independent and separate
works in themselves, then this License, and its terms, do not
apply to those sections when you distribute them as separate
works. But when you distribute the same sections as part of a
whole which is a work based on the Program, the distribution of
the whole must be on the terms of this License, whose permissions
for other licensees extend to the entire whole, and thus to each
and every part regardless of who wrote it.
Thus, it is not the intent of this section to claim rights or
contest your rights to work written entirely by you; rather, the
intent is to exercise the right to control the distribution of
derivative or collective works based on the Program.
In addition, mere aggregation of another work not based on the
Program with the Program (or with a work based on the Program) on
a volume of a storage or distribution medium does not bring the
other work under the scope of this License.
4. You may copy and distribute the Program (or a work based on it,
under Section 2) in object code or executable form under the terms
of Sections 1 and 2 above provided that you also do one of the
following:
a. Accompany it with the complete corresponding machine-readable
source code, which must be distributed under the terms of
Sections 1 and 2 above on a medium customarily used for
software interchange; or,
b. Accompany it with a written offer, valid for at least three
years, to give any third party, for a charge no more than your
cost of physically performing source distribution, a complete
machine-readable copy of the corresponding source code, to be
distributed under the terms of Sections 1 and 2 above on a
medium customarily used for software interchange; or,
c. Accompany it with the information you received as to the offer
to distribute corresponding source code. (This alternative is
allowed only for noncommercial distribution and only if you
received the program in object code or executable form with
such an offer, in accord with Subsection b above.)
The source code for a work means the preferred form of the work for
making modifications to it. For an executable work, complete
source code means all the source code for all modules it contains,
plus any associated interface definition files, plus the scripts
used to control compilation and installation of the executable.
However, as a special exception, the source code distributed need
not include anything that is normally distributed (in either
source or binary form) with the major components (compiler,
kernel, and so on) of the operating system on which the executable
runs, unless that component itself accompanies the executable.
If distribution of executable or object code is made by offering
access to copy from a designated place, then offering equivalent
access to copy the source code from the same place counts as
distribution of the source code, even though third parties are not
compelled to copy the source along with the object code.
5. You may not copy, modify, sublicense, or distribute the Program
except as expressly provided under this License. Any attempt
otherwise to copy, modify, sublicense or distribute the Program is
void, and will automatically terminate your rights under this
License. However, parties who have received copies, or rights,
from you under this License will not have their licenses
terminated so long as such parties remain in full compliance.
6. You are not required to accept this License, since you have not
signed it. However, nothing else grants you permission to modify
or distribute the Program or its derivative works. These actions
are prohibited by law if you do not accept this License.
Therefore, by modifying or distributing the Program (or any work
based on the Program), you indicate your acceptance of this
License to do so, and all its terms and conditions for copying,
distributing or modifying the Program or works based on it.
7. Each time you redistribute the Program (or any work based on the
Program), the recipient automatically receives a license from the
original licensor to copy, distribute or modify the Program
subject to these terms and conditions. You may not impose any
further restrictions on the recipients' exercise of the rights
granted herein. You are not responsible for enforcing compliance
by third parties to this License.
8. If, as a consequence of a court judgment or allegation of patent
infringement or for any other reason (not limited to patent
issues), conditions are imposed on you (whether by court order,
agreement or otherwise) that contradict the conditions of this
License, they do not excuse you from the conditions of this
License. If you cannot distribute so as to satisfy simultaneously
your obligations under this License and any other pertinent
obligations, then as a consequence you may not distribute the
Program at all. For example, if a patent license would not permit
royalty-free redistribution of the Program by all those who
receive copies directly or indirectly through you, then the only
way you could satisfy both it and this License would be to refrain
entirely from distribution of the Program.
If any portion of this section is held invalid or unenforceable
under any particular circumstance, the balance of the section is
intended to apply and the section as a whole is intended to apply
in other circumstances.
It is not the purpose of this section to induce you to infringe any
patents or other property right claims or to contest validity of
any such claims; this section has the sole purpose of protecting
the integrity of the free software distribution system, which is
implemented by public license practices. Many people have made
generous contributions to the wide range of software distributed
through that system in reliance on consistent application of that
system; it is up to the author/donor to decide if he or she is
willing to distribute software through any other system and a
licensee cannot impose that choice.
This section is intended to make thoroughly clear what is believed
to be a consequence of the rest of this License.
9. If the distribution and/or use of the Program is restricted in
certain countries either by patents or by copyrighted interfaces,
the original copyright holder who places the Program under this
License may add an explicit geographical distribution limitation
excluding those countries, so that distribution is permitted only
in or among countries not thus excluded. In such case, this
License incorporates the limitation as if written in the body of
this License.
10. The Free Software Foundation may publish revised and/or new
versions of the General Public License from time to time. Such
new versions will be similar in spirit to the present version, but
may differ in detail to address new problems or concerns.
Each version is given a distinguishing version number. If the
Program specifies a version number of this License which applies
to it and "any later version", you have the option of following
the terms and conditions either of that version or of any later
version published by the Free Software Foundation. If the Program
does not specify a version number of this License, you may choose
any version ever published by the Free Software Foundation.
11. If you wish to incorporate parts of the Program into other free
programs whose distribution conditions are different, write to the
author to ask for permission. For software which is copyrighted
by the Free Software Foundation, write to the Free Software
Foundation; we sometimes make exceptions for this. Our decision
will be guided by the two goals of preserving the free status of
all derivatives of our free software and of promoting the sharing
and reuse of software generally.
NO WARRANTY
12. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO
WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE
LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT
WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT
NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE
QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY
SERVICING, REPAIR OR CORRECTION.
13. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY
MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE
LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL,
INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR
INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU
OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY
OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN
ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
END OF TERMS AND CONDITIONS
How to Apply These Terms to Your New Programs
=============================================
If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these
terms.
To do so, attach the following notices to the program. It is safest
to attach them to the start of each source file to most effectively
convey the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.
ONE LINE TO GIVE THE PROGRAM'S NAME AND AN IDEA OF WHAT IT DOES.
Copyright (C) 19YY NAME OF AUTHOR
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., 675 Mass Ave, Cambridge, MA 02139, USA.
Also add information on how to contact you by electronic and paper
mail.
If the program is interactive, make it output a short notice like
this when it starts in an interactive mode:
Gnomovision version 69, Copyright (C) 19YY NAME OF AUTHOR
Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
type `show w'. This is free software, and you are welcome
to redistribute it under certain conditions; type `show c'
for details.
The hypothetical commands `show w' and `show c' should show the
appropriate parts of the General Public License. Of course, the
commands you use may be called something other than `show w' and `show
c'; they could even be mouse-clicks or menu items--whatever suits your
program.
You should also get your employer (if you work as a programmer) or
your school, if any, to sign a "copyright disclaimer" for the program,
if necessary. Here is a sample; alter the names:
Yoyodyne, Inc., hereby disclaims all copyright
interest in the program `Gnomovision'
(which makes passes at compilers) written
by James Hacker.
SIGNATURE OF TY COON, 1 April 1989
Ty Coon, President of Vice
This General Public License does not permit incorporating your
program into proprietary programs. If your program is a subroutine
library, you may consider it more useful to permit linking proprietary
applications with the library. If this is what you want to do, use the
GNU Library General Public License instead of this License.
GNU Free Documentation License
==============================
Version 1.1, March 2000
Copyright (C) 2000 Free Software Foundation, Inc.
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
0. PREAMBLE
The purpose of this License is to make a manual, textbook, or other
written document "free" in the sense of freedom: to assure everyone
the effective freedom to copy and redistribute it, with or without
modifying it, either commercially or noncommercially. Secondarily,
this License preserves for the author and publisher a way to get
credit for their work, while not being considered responsible for
modifications made by others.
This License is a kind of "copyleft", which means that derivative
works of the document must themselves be free in the same sense.
It complements the GNU General Public License, which is a copyleft
license designed for free software.
We have designed this License in order to use it for manuals for
free software, because free software needs free documentation: a
free program should come with manuals providing the same freedoms
that the software does. But this License is not limited to
software manuals; it can be used for any textual work, regardless
of subject matter or whether it is published as a printed book.
We recommend this License principally for works whose purpose is
instruction or reference.
1. APPLICABILITY AND DEFINITIONS
This License applies to any manual or other work that contains a
notice placed by the copyright holder saying it can be distributed
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any such manual or work. Any member of the public is a licensee,
and is addressed as "you".
A "Modified Version" of the Document means any work containing the
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A "Secondary Section" is a named appendix or a front-matter
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(For example, if the Document is in part a textbook of
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The relationship could be a matter of historical connection with
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The "Invariant Sections" are certain Secondary Sections whose
titles are designated, as being those of Invariant Sections, in
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License.
The "Cover Texts" are certain short passages of text that are
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A "Transparent" copy of the Document means a machine-readable copy,
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Opaque formats include PostScript, PDF, proprietary formats that
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The "Title Page" means, for a printed book, the title page itself,
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2. VERBATIM COPYING
You may copy and distribute the Document in any medium, either
commercially or noncommercially, provided that this License, the
copyright notices, and the license notice saying this License
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You may also lend copies, under the same conditions stated above,
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3. COPYING IN QUANTITY
If you publish printed copies of the Document numbering more than
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must enclose the copies in covers that carry, clearly and legibly,
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If the required texts for either cover are too voluminous to fit
legibly, you should put the first ones listed (as many as fit
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If you publish or distribute Opaque copies of the Document
numbering more than 100, you must either include a
machine-readable Transparent copy along with each Opaque copy, or
state in or with each Opaque copy a publicly-accessible
computer-network location containing a complete Transparent copy
of the Document, free of added material, which the general
network-using public has access to download anonymously at no
charge using public-standard network protocols. If you use the
latter option, you must take reasonably prudent steps, when you
begin distribution of Opaque copies in quantity, to ensure that
this Transparent copy will remain thus accessible at the stated
location until at least one year after the last time you
distribute an Opaque copy (directly or through your agents or
retailers) of that edition to the public.
It is requested, but not required, that you contact the authors of
the Document well before redistributing any large number of
copies, to give them a chance to provide you with an updated
version of the Document.
4. MODIFICATIONS
You may copy and distribute a Modified Version of the Document
under the conditions of sections 2 and 3 above, provided that you
release the Modified Version under precisely this License, with
the Modified Version filling the role of the Document, thus
licensing distribution and modification of the Modified Version to
whoever possesses a copy of it. In addition, you must do these
things in the Modified Version:
A. Use in the Title Page (and on the covers, if any) a title
distinct from that of the Document, and from those of previous
versions (which should, if there were any, be listed in the
History section of the Document). You may use the same title
as a previous version if the original publisher of that version
gives permission.
B. List on the Title Page, as authors, one or more persons or
entities responsible for authorship of the modifications in the
Modified Version, together with at least five of the principal
authors of the Document (all of its principal authors, if it
has less than five).
C. State on the Title page the name of the publisher of the
Modified Version, as the publisher.
D. Preserve all the copyright notices of the Document.
E. Add an appropriate copyright notice for your modifications
adjacent to the other copyright notices.
F. Include, immediately after the copyright notices, a license
notice giving the public permission to use the Modified Version
under the terms of this License, in the form shown in the
Addendum below.
G. Preserve in that license notice the full lists of Invariant
Sections and required Cover Texts given in the Document's
license notice.
H. Include an unaltered copy of this License.
I. Preserve the section entitled "History", and its title, and add
to it an item stating at least the title, year, new authors, and
publisher of the Modified Version as given on the Title Page.
If there is no section entitled "History" in the Document,
create one stating the title, year, authors, and publisher of
the Document as given on its Title Page, then add an item
describing the Modified Version as stated in the previous
sentence.
J. Preserve the network location, if any, given in the Document for
public access to a Transparent copy of the Document, and
likewise the network locations given in the Document for
previous versions it was based on. These may be placed in the
"History" section. You may omit a network location for a work
that was published at least four years before the Document
itself, or if the original publisher of the version it refers
to gives permission.
K. In any section entitled "Acknowledgements" or "Dedications",
preserve the section's title, and preserve in the section all the
substance and tone of each of the contributor acknowledgements
and/or dedications given therein.
L. Preserve all the Invariant Sections of the Document,
unaltered in their text and in their titles. Section numbers
or the equivalent are not considered part of the section titles.
M. Delete any section entitled "Endorsements". Such a section
may not be included in the Modified Version.
N. Do not retitle any existing section as "Endorsements" or to
conflict in title with any Invariant Section.
If the Modified Version includes new front-matter sections or
appendices that qualify as Secondary Sections and contain no
material copied from the Document, you may at your option
designate some or all of these sections as invariant. To do this,
add their titles to the list of Invariant Sections in the Modified
Version's license notice. These titles must be distinct from any
other section titles.
You may add a section entitled "Endorsements", provided it contains
nothing but endorsements of your Modified Version by various
parties-for example, statements of peer review or that the text has
been approved by an organization as the authoritative definition
of a standard.
You may add a passage of up to five words as a Front-Cover Text,
and a passage of up to 25 words as a Back-Cover Text, to the end
of the list of Cover Texts in the Modified Version. Only one
passage of Front-Cover Text and one of Back-Cover Text may be
added by (or through arrangements made by) any one entity. If the
Document already includes a cover text for the same cover,
previously added by you or by arrangement made by the same entity
you are acting on behalf of, you may not add another; but you may
replace the old one, on explicit permission from the previous
publisher that added the old one.
The author(s) and publisher(s) of the Document do not by this
License give permission to use their names for publicity for or to
assert or imply endorsement of any Modified Version.
5. COMBINING DOCUMENTS
You may combine the Document with other documents released under
this License, under the terms defined in section 4 above for
modified versions, provided that you include in the combination
all of the Invariant Sections of all of the original documents,
unmodified, and list them all as Invariant Sections of your
combined work in its license notice.
The combined work need only contain one copy of this License, and
multiple identical Invariant Sections may be replaced with a single
copy. If there are multiple Invariant Sections with the same name
but different contents, make the title of each such section unique
by adding at the end of it, in parentheses, the name of the
original author or publisher of that section if known, or else a
unique number. Make the same adjustment to the section titles in
the list of Invariant Sections in the license notice of the
combined work.
In the combination, you must combine any sections entitled
"History" in the various original documents, forming one section
entitled "History"; likewise combine any sections entitled
"Acknowledgements", and any sections entitled "Dedications". You
must delete all sections entitled "Endorsements."
6. COLLECTIONS OF DOCUMENTS
You may make a collection consisting of the Document and other
documents released under this License, and replace the individual
copies of this License in the various documents with a single copy
that is included in the collection, provided that you follow the
rules of this License for verbatim copying of each of the
documents in all other respects.
You may extract a single document from such a collection, and
distribute it individually under this License, provided you insert
a copy of this License into the extracted document, and follow
this License in all other respects regarding verbatim copying of
that document.
7. AGGREGATION WITH INDEPENDENT WORKS
A compilation of the Document or its derivatives with other
separate and independent documents or works, in or on a volume of
a storage or distribution medium, does not as a whole count as a
Modified Version of the Document, provided no compilation
copyright is claimed for the compilation. Such a compilation is
called an "aggregate", and this License does not apply to the
other self-contained works thus compiled with the Document, on
account of their being thus compiled, if they are not themselves
derivative works of the Document.
If the Cover Text requirement of section 3 is applicable to these
copies of the Document, then if the Document is less than one
quarter of the entire aggregate, the Document's Cover Texts may be
placed on covers that surround only the Document within the
aggregate. Otherwise they must appear on covers around the whole
aggregate.
8. TRANSLATION
Translation is considered a kind of modification, so you may
distribute translations of the Document under the terms of section
4. Replacing Invariant Sections with translations requires special
permission from their copyright holders, but you may include
translations of some or all Invariant Sections in addition to the
original versions of these Invariant Sections. You may include a
translation of this License provided that you also include the
original English version of this License. In case of a
disagreement between the translation and the original English
version of this License, the original English version will prevail.
9. TERMINATION
You may not copy, modify, sublicense, or distribute the Document
except as expressly provided for under this License. Any other
attempt to copy, modify, sublicense or distribute the Document is
void, and will automatically terminate your rights under this
License. However, parties who have received copies, or rights,
from you under this License will not have their licenses
terminated so long as such parties remain in full compliance.
10. FUTURE REVISIONS OF THIS LICENSE
The Free Software Foundation may publish new, revised versions of
the GNU Free Documentation License from time to time. Such new
versions will be similar in spirit to the present version, but may
differ in detail to address new problems or concerns. See
http://www.gnu.org/copyleft/.
Each version of the License is given a distinguishing version
number. If the Document specifies that a particular numbered
version of this License "or any later version" applies to it, you
have the option of following the terms and conditions either of
that specified version or of any later version that has been
published (not as a draft) by the Free Software Foundation. If
the Document does not specify a version number of this License,
you may choose any version ever published (not as a draft) by the
Free Software Foundation.
ADDENDUM: How to use this License for your documents
====================================================
To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and license
notices just after the title page:
Copyright (C) YEAR YOUR NAME.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1
or any later version published by the Free Software Foundation;
with the Invariant Sections being LIST THEIR TITLES, with the
Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
A copy of the license is included in the section entitled ``GNU
Free Documentation License''.
If you have no Invariant Sections, write "with no Invariant
Sections" instead of saying which ones are invariant. If you have no
Front-Cover Texts, write "no Front-Cover Texts" instead of "Front-Cover
Texts being LIST"; likewise for Back-Cover Texts.
If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of
free software license, such as the GNU General Public License, to
permit their use in free software.
Concept Index
*************
.html extension:
See ``HTTP Options''.
.listing files, removing:
See ``FTP Options''.
.netrc:
See ``Startup File''.
.wgetrc:
See ``Startup File''.
accept directories:
See ``Directory-Based Limits''.
accept suffixes:
See ``Types of Files''.
accept wildcards:
See ``Types of Files''.
append to log:
See ``Logging and Input File Options''.
arguments:
See ``Invoking''.
authentication:
See ``HTTP Options''.
backing up converted files:
See ``Recursive Retrieval Options''.
base for relative links in input file:
See ``Logging and Input File Options''.
bind() address:
See ``Download Options''.
bug reports:
See ``Reporting Bugs''.
bugs:
See ``Reporting Bugs''.
cache:
See ``HTTP Options''.
client IP address:
See ``Download Options''.
clobbering, file:
See ``Download Options''.
command line:
See ``Invoking''.
Content-Length, ignore:
See ``HTTP Options''.
continue retrieval:
See ``Download Options''.
contributors:
See ``Contributors''.
conversion of links:
See ``Recursive Retrieval Options''.
cookies:
See ``HTTP Options''.
cookies, loading:
See ``HTTP Options''.
cookies, saving:
See ``HTTP Options''.
copying:
See ``Copying''.
cut directories:
See ``Directory Options''.
debug:
See ``Logging and Input File Options''.
delete after retrieval:
See ``Recursive Retrieval Options''.
directories:
See ``Directory-Based Limits''.
directories, exclude:
See ``Directory-Based Limits''.
directories, include:
See ``Directory-Based Limits''.
directory limits:
See ``Directory-Based Limits''.
directory prefix:
See ``Directory Options''.
dot style:
See ``Download Options''.
downloading multiple times:
See ``Download Options''.
examples:
See ``Examples''.
exclude directories:
See ``Directory-Based Limits''.
execute wgetrc command:
See ``Basic Startup Options''.
features:
See ``Overview''.
filling proxy cache:
See ``Recursive Retrieval Options''.
follow FTP links:
See ``Recursive Accept/Reject Options''.
following ftp links:
See ``Following FTP Links''.
following links:
See ``Following Links''.
force html:
See ``Logging and Input File Options''.
free software:
See ``Copying''.
ftp time-stamping:
See ``FTP Time-Stamping Internals''.
GFDL:
See ``Copying''.
globbing, toggle:
See ``FTP Options''.
GPL:
See ``Copying''.
hangup:
See ``Signals''.
header, add:
See ``HTTP Options''.
hosts, spanning:
See ``Spanning Hosts''.
http password:
See ``HTTP Options''.
http referer:
See ``HTTP Options''.
http time-stamping:
See ``HTTP Time-Stamping Internals''.
http user:
See ``HTTP Options''.
ignore length:
See ``HTTP Options''.
include directories:
See ``Directory-Based Limits''.
incomplete downloads:
See ``Download Options''.
incremental updating:
See ``Time-Stamping''.
input-file:
See ``Logging and Input File Options''.
invoking:
See ``Invoking''.
IP address, client:
See ``Download Options''.
latest version:
See ``Distribution''.
link conversion:
See ``Recursive Retrieval Options''.
links:
See ``Following Links''.
list:
See ``Mailing List''.
loading cookies:
See ``HTTP Options''.
location of wgetrc:
See ``Wgetrc Location''.
log file:
See ``Logging and Input File Options''.
mailing list:
See ``Mailing List''.
mirroring:
See ``Very Advanced Usage''.
no parent:
See ``Directory-Based Limits''.
no warranty:
See ``GNU General Public License''.
no-clobber:
See ``Download Options''.
nohup:
See ``Invoking''.
number of retries:
See ``Download Options''.
operating systems:
See ``Portability''.
option syntax:
See ``Option Syntax''.
output file:
See ``Logging and Input File Options''.
overview:
See ``Overview''.
page requisites:
See ``Recursive Retrieval Options''.
passive ftp:
See ``FTP Options''.
pause:
See ``Download Options''.
portability:
See ``Portability''.
progress indicator:
See ``Download Options''.
proxies:
See ``Proxies''.
proxy <1>:
See ``HTTP Options''.
proxy:
See ``Download Options''.
proxy authentication:
See ``HTTP Options''.
proxy filling:
See ``Recursive Retrieval Options''.
proxy password:
See ``HTTP Options''.
proxy user:
See ``HTTP Options''.
quiet:
See ``Logging and Input File Options''.
quota:
See ``Download Options''.
random wait:
See ``Download Options''.
recursion:
See ``Recursive Retrieval''.
recursive retrieval:
See ``Recursive Retrieval''.
redirecting output:
See ``Advanced Usage''.
referer, http:
See ``HTTP Options''.
reject directories:
See ``Directory-Based Limits''.
reject suffixes:
See ``Types of Files''.
reject wildcards:
See ``Types of Files''.
relative links:
See ``Relative Links''.
reporting bugs:
See ``Reporting Bugs''.
required images, downloading:
See ``Recursive Retrieval Options''.
resume download:
See ``Download Options''.
retries:
See ``Download Options''.
retries, waiting between:
See ``Download Options''.
retrieving:
See ``Recursive Retrieval''.
robots:
See ``Robots''.
robots.txt:
See ``Robots''.
sample wgetrc:
See ``Sample Wgetrc''.
saving cookies:
See ``HTTP Options''.
security:
See ``Security Considerations''.
server maintenance:
See ``Robots''.
server response, print:
See ``Download Options''.
server response, save:
See ``HTTP Options''.
signal handling:
See ``Signals''.
spanning hosts:
See ``Spanning Hosts''.
spider:
See ``Download Options''.
startup:
See ``Startup File''.
startup file:
See ``Startup File''.
suffixes, accept:
See ``Types of Files''.
suffixes, reject:
See ``Types of Files''.
symbolic links, retrieving:
See ``FTP Options''.
syntax of options:
See ``Option Syntax''.
syntax of wgetrc:
See ``Wgetrc Syntax''.
tag-based recursive pruning:
See ``Recursive Accept/Reject Options''.
time-stamping:
See ``Time-Stamping''.
time-stamping usage:
See ``Time-Stamping Usage''.
timeout:
See ``Download Options''.
timestamping:
See ``Time-Stamping''.
tries:
See ``Download Options''.
types of files:
See ``Types of Files''.
updating the archives:
See ``Time-Stamping''.
URL:
See ``URL Format''.
URL syntax:
See ``URL Format''.
usage, time-stamping:
See ``Time-Stamping Usage''.
user-agent:
See ``HTTP Options''.
various:
See ``Various''.
verbose:
See ``Logging and Input File Options''.
wait:
See ``Download Options''.
wait, random:
See ``Download Options''.
waiting between retries:
See ``Download Options''.
Wget as spider:
See ``Download Options''.
wgetrc:
See ``Startup File''.
wgetrc commands:
See ``Wgetrc Commands''.
wgetrc location:
See ``Wgetrc Location''.
wgetrc syntax:
See ``Wgetrc Syntax''.
wildcards, accept:
See ``Types of Files''.
wildcards, reject:
See ``Types of Files''.
...Table of Contents...