1 \input texinfo @c -*-texinfo-*-
5 @settitle GNU Wget Manual
6 @c Disable the monstrous rectangles beside overfull hbox-es.
8 @c Use `odd' to print double-sided.
13 @c Remove this if you don't use A4 paper.
17 @c This should really be generated automatically, possibly by including
18 @c an auto-generated file.
20 @set UPDATED September 2003
22 @dircategory Net Utilities
23 @dircategory World Wide Web
25 * Wget: (wget). The non-interactive network downloader.
29 This file documents the the GNU Wget utility for downloading network
32 @c man begin COPYRIGHT
33 Copyright @copyright{} 1996, 1997, 1998, 2000, 2001 Free Software
36 Permission is granted to make and distribute verbatim copies of
37 this manual provided the copyright notice and this permission notice
38 are preserved on all copies.
41 Permission is granted to process this file through TeX and print the
42 results, provided the printed document carries a copying permission
43 notice identical to this one except for the removal of this paragraph
44 (this paragraph not being relevant to the printed manual).
46 Permission is granted to copy, distribute and/or modify this document
47 under the terms of the GNU Free Documentation License, Version 1.1 or
48 any later version published by the Free Software Foundation; with the
49 Invariant Sections being ``GNU General Public License'' and ``GNU Free
50 Documentation License'', with no Front-Cover Texts, and with no
51 Back-Cover Texts. A copy of the license is included in the section
52 entitled ``GNU Free Documentation License''.
58 @subtitle The noninteractive downloading utility
59 @subtitle Updated for Wget @value{VERSION}, @value{UPDATED}
60 @author by Hrvoje Nik@v{s}i@'{c} and the developers
64 Originally written by Hrvoje Niksic <hniksic@arsdigita.com>.
67 GNU Info entry for @file{wget}.
72 @vskip 0pt plus 1filll
73 Copyright @copyright{} 1996, 1997, 1998, 2000, 2001 Free Software
76 Permission is granted to copy, distribute and/or modify this document
77 under the terms of the GNU Free Documentation License, Version 1.1 or
78 any later version published by the Free Software Foundation; with the
79 Invariant Sections being ``GNU General Public License'' and ``GNU Free
80 Documentation License'', with no Front-Cover Texts, and with no
81 Back-Cover Texts. A copy of the license is included in the section
82 entitled ``GNU Free Documentation License''.
86 @node Top, Overview, (dir), (dir)
87 @top Wget @value{VERSION}
89 This manual documents version @value{VERSION} of GNU Wget, the freely
90 available utility for network download.
92 Copyright @copyright{} 1996, 1997, 1998, 2000, 2001 Free Software
96 * Overview:: Features of Wget.
97 * Invoking:: Wget command-line arguments.
98 * Recursive Retrieval:: Description of recursive retrieval.
99 * Following Links:: The available methods of chasing links.
100 * Time-Stamping:: Mirroring according to time-stamps.
101 * Startup File:: Wget's initialization file.
102 * Examples:: Examples of usage.
103 * Various:: The stuff that doesn't fit anywhere else.
104 * Appendices:: Some useful references.
105 * Copying:: You may give out copies of Wget and of this manual.
106 * Concept Index:: Topics covered by this manual.
110 @node Overview, Invoking, Top, Top
115 @c man begin DESCRIPTION
116 GNU Wget is a free utility for non-interactive download of files from
117 the Web. It supports @sc{http}, @sc{https}, and @sc{ftp} protocols, as
118 well as retrieval through @sc{http} proxies.
121 This chapter is a partial overview of Wget's features.
125 @c man begin DESCRIPTION
126 Wget is non-interactive, meaning that it can work in the background,
127 while the user is not logged on. This allows you to start a retrieval
128 and disconnect from the system, letting Wget finish the work. By
129 contrast, most of the Web browsers require constant user's presence,
130 which can be a great hindrance when transferring a lot of data.
136 @c man begin DESCRIPTION
140 @c man begin DESCRIPTION
141 Wget can follow links in @sc{html} pages and create local versions of
142 remote web sites, fully recreating the directory structure of the
143 original site. This is sometimes referred to as ``recursive
144 downloading.'' While doing that, Wget respects the Robot Exclusion
145 Standard (@file{/robots.txt}). Wget can be instructed to convert the
146 links in downloaded @sc{html} files to the local files for offline
152 File name wildcard matching and recursive mirroring of directories are
153 available when retrieving via @sc{ftp}. Wget can read the time-stamp
154 information given by both @sc{http} and @sc{ftp} servers, and store it
155 locally. Thus Wget can see if the remote file has changed since last
156 retrieval, and automatically retrieve the new version if it has. This
157 makes Wget suitable for mirroring of @sc{ftp} sites, as well as home
163 @c man begin DESCRIPTION
167 @c man begin DESCRIPTION
168 Wget has been designed for robustness over slow or unstable network
169 connections; if a download fails due to a network problem, it will
170 keep retrying until the whole file has been retrieved. If the server
171 supports regetting, it will instruct the server to continue the
172 download from where it left off.
177 Wget supports proxy servers, which can lighten the network load, speed
178 up retrieval and provide access behind firewalls. However, if you are
179 behind a firewall that requires that you use a socks style gateway, you
180 can get the socks library and build Wget with support for socks. Wget
181 also supports the passive @sc{ftp} downloading as an option.
185 Builtin features offer mechanisms to tune which links you wish to follow
186 (@pxref{Following Links}).
190 The retrieval is conveniently traced with printing dots, each dot
191 representing a fixed amount of data received (1KB by default). These
192 representations can be customized to your preferences.
196 Most of the features are fully configurable, either through command line
197 options, or via the initialization file @file{.wgetrc} (@pxref{Startup
198 File}). Wget allows you to define @dfn{global} startup files
199 (@file{/usr/local/etc/wgetrc} by default) for site settings.
204 @item /usr/local/etc/wgetrc
205 Default location of the @dfn{global} startup file.
215 Finally, GNU Wget is free software. This means that everyone may use
216 it, redistribute it and/or modify it under the terms of the GNU General
217 Public License, as published by the Free Software Foundation
221 @node Invoking, Recursive Retrieval, Overview, Top
228 By default, Wget is very simple to invoke. The basic syntax is:
231 @c man begin SYNOPSIS
232 wget [@var{option}]@dots{} [@var{URL}]@dots{}
236 Wget will simply download all the @sc{url}s specified on the command
237 line. @var{URL} is a @dfn{Uniform Resource Locator}, as defined below.
239 However, you may wish to change some of the default parameters of
240 Wget. You can do it two ways: permanently, adding the appropriate
241 command to @file{.wgetrc} (@pxref{Startup File}), or specifying it on
247 * Basic Startup Options::
248 * Logging and Input File Options::
250 * Directory Options::
253 * Recursive Retrieval Options::
254 * Recursive Accept/Reject Options::
257 @node URL Format, Option Syntax, Invoking, Invoking
262 @dfn{URL} is an acronym for Uniform Resource Locator. A uniform
263 resource locator is a compact string representation for a resource
264 available via the Internet. Wget recognizes the @sc{url} syntax as per
265 @sc{rfc1738}. This is the most widely used form (square brackets denote
269 http://host[:port]/directory/file
270 ftp://host[:port]/directory/file
273 You can also encode your username and password within a @sc{url}:
276 ftp://user:password@@host/path
277 http://user:password@@host/path
280 Either @var{user} or @var{password}, or both, may be left out. If you
281 leave out either the @sc{http} username or password, no authentication
282 will be sent. If you leave out the @sc{ftp} username, @samp{anonymous}
283 will be used. If you leave out the @sc{ftp} password, your email
284 address will be supplied as a default password.@footnote{If you have a
285 @file{.netrc} file in your home directory, password will also be
288 @strong{Important Note}: if you specify a password-containing @sc{url}
289 on the command line, the username and password will be plainly visible
290 to all users on the system, by way of @code{ps}. On multi-user systems,
291 this is a big security risk. To work around it, use @code{wget -i -}
292 and feed the @sc{url}s to Wget's standard input, each on a separate
293 line, terminated by @kbd{C-d}.
295 You can encode unsafe characters in a @sc{url} as @samp{%xy}, @code{xy}
296 being the hexadecimal representation of the character's @sc{ascii}
297 value. Some common unsafe characters include @samp{%} (quoted as
298 @samp{%25}), @samp{:} (quoted as @samp{%3A}), and @samp{@@} (quoted as
299 @samp{%40}). Refer to @sc{rfc1738} for a comprehensive list of unsafe
302 Wget also supports the @code{type} feature for @sc{ftp} @sc{url}s. By
303 default, @sc{ftp} documents are retrieved in the binary mode (type
304 @samp{i}), which means that they are downloaded unchanged. Another
305 useful mode is the @samp{a} (@dfn{ASCII}) mode, which converts the line
306 delimiters between the different operating systems, and is thus useful
307 for text files. Here is an example:
310 ftp://host/directory/file;type=a
313 Two alternative variants of @sc{url} specification are also supported,
314 because of historical (hysterical?) reasons and their widespreaded use.
316 @sc{ftp}-only syntax (supported by @code{NcFTP}):
321 @sc{http}-only syntax (introduced by @code{Netscape}):
326 These two alternative forms are deprecated, and may cease being
327 supported in the future.
329 If you do not understand the difference between these notations, or do
330 not know which one to use, just use the plain ordinary format you use
331 with your favorite browser, like @code{Lynx} or @code{Netscape}.
333 @node Option Syntax, Basic Startup Options, URL Format, Invoking
334 @section Option Syntax
335 @cindex option syntax
336 @cindex syntax of options
338 Since Wget uses GNU getopts to process its arguments, every option has a
339 short form and a long form. Long options are more convenient to
340 remember, but take time to type. You may freely mix different option
341 styles, or specify options after the command-line arguments. Thus you
345 wget -r --tries=10 http://fly.srk.fer.hr/ -o log
348 The space between the option accepting an argument and the argument may
349 be omitted. Instead @samp{-o log} you can write @samp{-olog}.
351 You may put several options that do not require arguments together,
358 This is a complete equivalent of:
361 wget -d -r -c @var{URL}
364 Since the options can be specified after the arguments, you may
365 terminate them with @samp{--}. So the following will try to download
366 @sc{url} @samp{-x}, reporting failure to @file{log}:
372 The options that accept comma-separated lists all respect the convention
373 that specifying an empty list clears its value. This can be useful to
374 clear the @file{.wgetrc} settings. For instance, if your @file{.wgetrc}
375 sets @code{exclude_directories} to @file{/cgi-bin}, the following
376 example will first reset it, and then set it to exclude @file{/~nobody}
377 and @file{/~somebody}. You can also clear the lists in @file{.wgetrc}
378 (@pxref{Wgetrc Syntax}).
381 wget -X '' -X /~nobody,/~somebody
386 @node Basic Startup Options, Logging and Input File Options, Option Syntax, Invoking
387 @section Basic Startup Options
392 Display the version of Wget.
396 Print a help message describing all of Wget's command-line options.
400 Go to background immediately after startup. If no output file is
401 specified via the @samp{-o}, output is redirected to @file{wget-log}.
403 @cindex execute wgetrc command
404 @item -e @var{command}
405 @itemx --execute @var{command}
406 Execute @var{command} as if it were a part of @file{.wgetrc}
407 (@pxref{Startup File}). A command thus invoked will be executed
408 @emph{after} the commands in @file{.wgetrc}, thus taking precedence over
412 @node Logging and Input File Options, Download Options, Basic Startup Options, Invoking
413 @section Logging and Input File Options
418 @item -o @var{logfile}
419 @itemx --output-file=@var{logfile}
420 Log all messages to @var{logfile}. The messages are normally reported
423 @cindex append to log
424 @item -a @var{logfile}
425 @itemx --append-output=@var{logfile}
426 Append to @var{logfile}. This is the same as @samp{-o}, only it appends
427 to @var{logfile} instead of overwriting the old log file. If
428 @var{logfile} does not exist, a new file is created.
433 Turn on debug output, meaning various information important to the
434 developers of Wget if it does not work properly. Your system
435 administrator may have chosen to compile Wget without debug support, in
436 which case @samp{-d} will not work. Please note that compiling with
437 debug support is always safe---Wget compiled with the debug support will
438 @emph{not} print any debug info unless requested with @samp{-d}.
439 @xref{Reporting Bugs}, for more information on how to use @samp{-d} for
445 Turn off Wget's output.
450 Turn on verbose output, with all the available data. The default output
455 Non-verbose output---turn off verbose without being completely quiet
456 (use @samp{-q} for that), which means that error messages and basic
457 information still get printed.
461 @itemx --input-file=@var{file}
462 Read @sc{url}s from @var{file}, in which case no @sc{url}s need to be on
463 the command line. If there are @sc{url}s both on the command line and
464 in an input file, those on the command lines will be the first ones to
465 be retrieved. The @var{file} need not be an @sc{html} document (but no
466 harm if it is)---it is enough if the @sc{url}s are just listed
469 However, if you specify @samp{--force-html}, the document will be
470 regarded as @samp{html}. In that case you may have problems with
471 relative links, which you can solve either by adding @code{<base
472 href="@var{url}">} to the documents or by specifying
473 @samp{--base=@var{url}} on the command line.
478 When input is read from a file, force it to be treated as an @sc{html}
479 file. This enables you to retrieve relative links from existing
480 @sc{html} files on your local disk, by adding @code{<base
481 href="@var{url}">} to @sc{html}, or using the @samp{--base} command-line
484 @cindex base for relative links in input file
486 @itemx --base=@var{URL}
487 When used in conjunction with @samp{-F}, prepends @var{URL} to relative
488 links in the file specified by @samp{-i}.
491 @node Download Options, Directory Options, Logging and Input File Options, Invoking
492 @section Download Options
495 @cindex bind() address
496 @cindex client IP address
497 @cindex IP address, client
498 @item --bind-address=@var{ADDRESS}
499 When making client TCP/IP connections, @code{bind()} to @var{ADDRESS} on
500 the local machine. @var{ADDRESS} may be specified as a hostname or IP
501 address. This option can be useful if your machine is bound to multiple
506 @cindex number of retries
507 @item -t @var{number}
508 @itemx --tries=@var{number}
509 Set number of retries to @var{number}. Specify 0 or @samp{inf} for
513 @itemx --output-document=@var{file}
514 The documents will not be written to the appropriate files, but all will
515 be concatenated together and written to @var{file}. If @var{file}
516 already exists, it will be overwritten. If the @var{file} is @samp{-},
517 the documents will be written to standard output. Including this option
518 automatically sets the number of tries to 1.
520 @cindex clobbering, file
521 @cindex downloading multiple times
525 If a file is downloaded more than once in the same directory, Wget's
526 behavior depends on a few options, including @samp{-nc}. In certain
527 cases, the local file will be @dfn{clobbered}, or overwritten, upon
528 repeated download. In other cases it will be preserved.
530 When running Wget without @samp{-N}, @samp{-nc}, or @samp{-r},
531 downloading the same file in the same directory will result in the
532 original copy of @var{file} being preserved and the second copy being
533 named @samp{@var{file}.1}. If that file is downloaded yet again, the
534 third copy will be named @samp{@var{file}.2}, and so on. When
535 @samp{-nc} is specified, this behavior is suppressed, and Wget will
536 refuse to download newer copies of @samp{@var{file}}. Therefore,
537 ``@code{no-clobber}'' is actually a misnomer in this mode---it's not
538 clobbering that's prevented (as the numeric suffixes were already
539 preventing clobbering), but rather the multiple version saving that's
542 When running Wget with @samp{-r}, but without @samp{-N} or @samp{-nc},
543 re-downloading a file will result in the new copy simply overwriting the
544 old. Adding @samp{-nc} will prevent this behavior, instead causing the
545 original version to be preserved and any newer copies on the server to
548 When running Wget with @samp{-N}, with or without @samp{-r}, the
549 decision as to whether or not to download a newer copy of a file depends
550 on the local and remote timestamp and size of the file
551 (@pxref{Time-Stamping}). @samp{-nc} may not be specified at the same
554 Note that when @samp{-nc} is specified, files with the suffixes
555 @samp{.html} or (yuck) @samp{.htm} will be loaded from the local disk
556 and parsed as if they had been retrieved from the Web.
558 @cindex continue retrieval
559 @cindex incomplete downloads
560 @cindex resume download
563 Continue getting a partially-downloaded file. This is useful when you
564 want to finish up a download started by a previous instance of Wget, or
565 by another program. For instance:
568 wget -c ftp://sunsite.doc.ic.ac.uk/ls-lR.Z
571 If there is a file named @file{ls-lR.Z} in the current directory, Wget
572 will assume that it is the first portion of the remote file, and will
573 ask the server to continue the retrieval from an offset equal to the
574 length of the local file.
576 Note that you don't need to specify this option if you just want the
577 current invocation of Wget to retry downloading a file should the
578 connection be lost midway through. This is the default behavior.
579 @samp{-c} only affects resumption of downloads started @emph{prior} to
580 this invocation of Wget, and whose local files are still sitting around.
582 Without @samp{-c}, the previous example would just download the remote
583 file to @file{ls-lR.Z.1}, leaving the truncated @file{ls-lR.Z} file
586 Beginning with Wget 1.7, if you use @samp{-c} on a non-empty file, and
587 it turns out that the server does not support continued downloading,
588 Wget will refuse to start the download from scratch, which would
589 effectively ruin existing contents. If you really want the download to
590 start from scratch, remove the file.
592 Also beginning with Wget 1.7, if you use @samp{-c} on a file which is of
593 equal size as the one on the server, Wget will refuse to download the
594 file and print an explanatory message. The same happens when the file
595 is smaller on the server than locally (presumably because it was changed
596 on the server since your last download attempt)---because ``continuing''
597 is not meaningful, no download occurs.
599 On the other side of the coin, while using @samp{-c}, any file that's
600 bigger on the server than locally will be considered an incomplete
601 download and only @code{(length(remote) - length(local))} bytes will be
602 downloaded and tacked onto the end of the local file. This behavior can
603 be desirable in certain cases---for instance, you can use @samp{wget -c}
604 to download just the new portion that's been appended to a data
605 collection or log file.
607 However, if the file is bigger on the server because it's been
608 @emph{changed}, as opposed to just @emph{appended} to, you'll end up
609 with a garbled file. Wget has no way of verifying that the local file
610 is really a valid prefix of the remote file. You need to be especially
611 careful of this when using @samp{-c} in conjunction with @samp{-r},
612 since every file will be considered as an "incomplete download" candidate.
614 Another instance where you'll get a garbled file if you try to use
615 @samp{-c} is if you have a lame @sc{http} proxy that inserts a
616 ``transfer interrupted'' string into the local file. In the future a
617 ``rollback'' option may be added to deal with this case.
619 Note that @samp{-c} only works with @sc{ftp} servers and with @sc{http}
620 servers that support the @code{Range} header.
622 @cindex progress indicator
624 @item --progress=@var{type}
625 Select the type of the progress indicator you wish to use. Legal
626 indicators are ``dot'' and ``bar''.
628 The ``bar'' indicator is used by default. It draws an ASCII progress
629 bar graphics (a.k.a ``thermometer'' display) indicating the status of
630 retrieval. If the output is not a TTY, the ``dot'' bar will be used by
633 Use @samp{--progress=dot} to switch to the ``dot'' display. It traces
634 the retrieval by printing dots on the screen, each dot representing a
635 fixed amount of downloaded data.
637 When using the dotted retrieval, you may also set the @dfn{style} by
638 specifying the type as @samp{dot:@var{style}}. Different styles assign
639 different meaning to one dot. With the @code{default} style each dot
640 represents 1K, there are ten dots in a cluster and 50 dots in a line.
641 The @code{binary} style has a more ``computer''-like orientation---8K
642 dots, 16-dots clusters and 48 dots per line (which makes for 384K
643 lines). The @code{mega} style is suitable for downloading very large
644 files---each dot represents 64K retrieved, there are eight dots in a
645 cluster, and 48 dots on each line (so each line contains 3M).
647 Note that you can set the default style using the @code{progress}
648 command in @file{.wgetrc}. That setting may be overridden from the
649 command line. The exception is that, when the output is not a TTY, the
650 ``dot'' progress will be favored over ``bar''. To force the bar output,
651 use @samp{--progress=bar:force}.
654 @itemx --timestamping
655 Turn on time-stamping. @xref{Time-Stamping}, for details.
657 @cindex server response, print
659 @itemx --server-response
660 Print the headers sent by @sc{http} servers and responses sent by
663 @cindex Wget as spider
666 When invoked with this option, Wget will behave as a Web @dfn{spider},
667 which means that it will not download the pages, just check that they
668 are there. You can use it to check your bookmarks, e.g. with:
671 wget --spider --force-html -i bookmarks.html
674 This feature needs much more work for Wget to get close to the
675 functionality of real @sc{www} spiders.
679 @itemx --timeout=@var{seconds}
680 Set the network timeout to @var{seconds} seconds. Whenever Wget
681 connects to or reads from a remote host, it checks for a timeout and
682 aborts the operation if the time expires. This prevents anomalous
683 occurrences such as hanging reads or infinite connects. The default
684 timeout is 900 seconds (fifteen minutes). Setting timeout to 0 will
685 disable checking for timeouts.
687 Please do not lower the default timeout value with this option unless
688 you know what you are doing.
690 @cindex bandwidth, limit
692 @cindex limit bandwidth
693 @item --limit-rate=@var{amount}
694 Limit the download speed to @var{amount} bytes per second. Amount may
695 be expressed in bytes, kilobytes with the @samp{k} suffix, or megabytes
696 with the @samp{m} suffix. For example, @samp{--limit-rate=20k} will
697 limit the retrieval rate to 20KB/s. This kind of thing is useful when,
698 for whatever reason, you don't want Wget to consume the entire evailable
701 Note that Wget implementeds the limiting by sleeping the appropriate
702 amount of time after a network read that took less time than specified
703 by the rate. Eventually this strategy causes the TCP transfer to slow
704 down to approximately the specified rate. However, it takes some time
705 for this balance to be achieved, so don't be surprised if limiting the
706 rate doesn't work with very small files. Also, the "sleeping" strategy
707 will misfire when an extremely small bandwidth, say less than 1.5KB/s,
712 @item -w @var{seconds}
713 @itemx --wait=@var{seconds}
714 Wait the specified number of seconds between the retrievals. Use of
715 this option is recommended, as it lightens the server load by making the
716 requests less frequent. Instead of in seconds, the time can be
717 specified in minutes using the @code{m} suffix, in hours using @code{h}
718 suffix, or in days using @code{d} suffix.
720 Specifying a large value for this option is useful if the network or the
721 destination host is down, so that Wget can wait long enough to
722 reasonably expect the network error to be fixed before the retry.
724 @cindex retries, waiting between
725 @cindex waiting between retries
726 @item --waitretry=@var{seconds}
727 If you don't want Wget to wait between @emph{every} retrieval, but only
728 between retries of failed downloads, you can use this option. Wget will
729 use @dfn{linear backoff}, waiting 1 second after the first failure on a
730 given file, then waiting 2 seconds after the second failure on that
731 file, up to the maximum number of @var{seconds} you specify. Therefore,
732 a value of 10 will actually make Wget wait up to (1 + 2 + ... + 10) = 55
735 Note that this option is turned on by default in the global
741 Some web sites may perform log analysis to identify retrieval programs
742 such as Wget by looking for statistically significant similarities in
743 the time between requests. This option causes the time between requests
744 to vary between 0 and 2 * @var{wait} seconds, where @var{wait} was
745 specified using the @samp{-w} or @samp{--wait} options, in order to mask
746 Wget's presence from such analysis.
748 A recent article in a publication devoted to development on a popular
749 consumer platform provided code to perform this analysis on the fly.
750 Its author suggested blocking at the class C address level to ensure
751 automated retrieval programs were blocked despite changing DHCP-supplied
754 The @samp{--random-wait} option was inspired by this ill-advised
755 recommendation to block many unrelated users from a web site due to the
760 @itemx --proxy=on/off
761 Turn proxy support on or off. The proxy is on by default if the
762 appropriate environmental variable is defined.
766 @itemx --quota=@var{quota}
767 Specify download quota for automatic retrievals. The value can be
768 specified in bytes (default), kilobytes (with @samp{k} suffix), or
769 megabytes (with @samp{m} suffix).
771 Note that quota will never affect downloading a single file. So if you
772 specify @samp{wget -Q10k ftp://wuarchive.wustl.edu/ls-lR.gz}, all of the
773 @file{ls-lR.gz} will be downloaded. The same goes even when several
774 @sc{url}s are specified on the command-line. However, quota is
775 respected when retrieving either recursively, or from an input file.
776 Thus you may safely type @samp{wget -Q2m -i sites}---download will be
777 aborted when the quota is exceeded.
779 Setting quota to 0 or to @samp{inf} unlimits the download quota.
782 @cindex caching of DNS lookups
783 @itemx --dns-cache=off
784 Turn off caching of DNS lookups. Normally, Wget remembers the addresses
785 it looked up from DNS so it doesn't have to repeatedly contact the DNS
786 server for the same (typically small) set of addresses it retrieves
787 from. This cache exists in memory only; a new Wget run will contact DNS
790 However, in some cases it is not desirable to cache host names, even for
791 the duration of a short-running application like Wget. For example,
792 some HTTP servers are hosted on machines with dynamically allocated IP
793 addresses that change from time to time. Their DNS entries are updated
794 along with each change. When Wget's download from such a host gets
795 interrupted by IP address change, Wget retries the download, but (due to
796 DNS caching) it contacts the old address. With the DNS cache turned
797 off, Wget will repeat the DNS lookup for every connect and will thus get
798 the correct dynamic address every time---at the cost of additional DNS
799 lookups where they're probably not needed.
801 If you don't understand the above description, you probably won't need
805 @node Directory Options, HTTP Options, Download Options, Invoking
806 @section Directory Options
810 @itemx --no-directories
811 Do not create a hierarchy of directories when retrieving recursively.
812 With this option turned on, all files will get saved to the current
813 directory, without clobbering (if a name shows up more than once, the
814 filenames will get extensions @samp{.n}).
817 @itemx --force-directories
818 The opposite of @samp{-nd}---create a hierarchy of directories, even if
819 one would not have been created otherwise. E.g. @samp{wget -x
820 http://fly.srk.fer.hr/robots.txt} will save the downloaded file to
821 @file{fly.srk.fer.hr/robots.txt}.
824 @itemx --no-host-directories
825 Disable generation of host-prefixed directories. By default, invoking
826 Wget with @samp{-r http://fly.srk.fer.hr/} will create a structure of
827 directories beginning with @file{fly.srk.fer.hr/}. This option disables
830 @cindex cut directories
831 @item --cut-dirs=@var{number}
832 Ignore @var{number} directory components. This is useful for getting a
833 fine-grained control over the directory where recursive retrieval will
836 Take, for example, the directory at
837 @samp{ftp://ftp.xemacs.org/pub/xemacs/}. If you retrieve it with
838 @samp{-r}, it will be saved locally under
839 @file{ftp.xemacs.org/pub/xemacs/}. While the @samp{-nH} option can
840 remove the @file{ftp.xemacs.org/} part, you are still stuck with
841 @file{pub/xemacs}. This is where @samp{--cut-dirs} comes in handy; it
842 makes Wget not ``see'' @var{number} remote directory components. Here
843 are several examples of how @samp{--cut-dirs} option works.
847 No options -> ftp.xemacs.org/pub/xemacs/
849 -nH --cut-dirs=1 -> xemacs/
850 -nH --cut-dirs=2 -> .
852 --cut-dirs=1 -> ftp.xemacs.org/xemacs/
857 If you just want to get rid of the directory structure, this option is
858 similar to a combination of @samp{-nd} and @samp{-P}. However, unlike
859 @samp{-nd}, @samp{--cut-dirs} does not lose with subdirectories---for
860 instance, with @samp{-nH --cut-dirs=1}, a @file{beta/} subdirectory will
861 be placed to @file{xemacs/beta}, as one would expect.
863 @cindex directory prefix
864 @item -P @var{prefix}
865 @itemx --directory-prefix=@var{prefix}
866 Set directory prefix to @var{prefix}. The @dfn{directory prefix} is the
867 directory where all other files and subdirectories will be saved to,
868 i.e. the top of the retrieval tree. The default is @samp{.} (the
872 @node HTTP Options, FTP Options, Directory Options, Invoking
873 @section HTTP Options
876 @cindex .html extension
878 @itemx --html-extension
879 If a file of type @samp{text/html} is downloaded and the URL does not
880 end with the regexp @samp{\.[Hh][Tt][Mm][Ll]?}, this option will cause
881 the suffix @samp{.html} to be appended to the local filename. This is
882 useful, for instance, when you're mirroring a remote site that uses
883 @samp{.asp} pages, but you want the mirrored pages to be viewable on
884 your stock Apache server. Another good use for this is when you're
885 downloading the output of CGIs. A URL like
886 @samp{http://site.com/article.cgi?25} will be saved as
887 @file{article.cgi?25.html}.
889 Note that filenames changed in this way will be re-downloaded every time
890 you re-mirror a site, because Wget can't tell that the local
891 @file{@var{X}.html} file corresponds to remote URL @samp{@var{X}} (since
892 it doesn't yet know that the URL produces output of type
893 @samp{text/html}. To prevent this re-downloading, you must use
894 @samp{-k} and @samp{-K} so that the original version of the file will be
895 saved as @file{@var{X}.orig} (@pxref{Recursive Retrieval Options}).
898 @cindex http password
899 @cindex authentication
900 @item --http-user=@var{user}
901 @itemx --http-passwd=@var{password}
902 Specify the username @var{user} and password @var{password} on an
903 @sc{http} server. According to the type of the challenge, Wget will
904 encode them using either the @code{basic} (insecure) or the
905 @code{digest} authentication scheme.
907 Another way to specify username and password is in the @sc{url} itself
908 (@pxref{URL Format}). Either method reveals your password to anyone who
909 bothers to run @code{ps}. To prevent the passwords from being seen,
910 store them in @file{.wgetrc} or @file{.netrc}, and make sure to protect
911 those files from other users with @code{chmod}. If the passwords are
912 really important, do not leave them lying in those files either---edit
913 the files and delete them after Wget has started the download.
915 For more information about security issues with Wget, @xref{Security
921 @itemx --cache=on/off
922 When set to off, disable server-side cache. In this case, Wget will
923 send the remote server an appropriate directive (@samp{Pragma:
924 no-cache}) to get the file from the remote service, rather than
925 returning the cached version. This is especially useful for retrieving
926 and flushing out-of-date documents on proxy servers.
928 Caching is allowed by default.
931 @item --cookies=on/off
932 When set to off, disable the use of cookies. Cookies are a mechanism
933 for maintaining server-side state. The server sends the client a cookie
934 using the @code{Set-Cookie} header, and the client responds with the
935 same cookie upon further requests. Since cookies allow the server
936 owners to keep track of visitors and for sites to exchange this
937 information, some consider them a breach of privacy. The default is to
938 use cookies; however, @emph{storing} cookies is not on by default.
940 @cindex loading cookies
941 @cindex cookies, loading
942 @item --load-cookies @var{file}
943 Load cookies from @var{file} before the first HTTP retrieval.
944 @var{file} is a textual file in the format originally used by Netscape's
945 @file{cookies.txt} file.
947 You will typically use this option when mirroring sites that require
948 that you be logged in to access some or all of their content. The login
949 process typically works by the web server issuing an @sc{http} cookie
950 upon receiving and verifying your credentials. The cookie is then
951 resent by the browser when accessing that part of the site, and so
952 proves your identity.
954 Mirroring such a site requires Wget to send the same cookies your
955 browser sends when communicating with the site. This is achieved by
956 @samp{--load-cookies}---simply point Wget to the location of the
957 @file{cookies.txt} file, and it will send the same cookies your browser
958 would send in the same situation. Different browsers keep textual
959 cookie files in different locations:
963 The cookies are in @file{~/.netscape/cookies.txt}.
965 @item Mozilla and Netscape 6.x.
966 Mozilla's cookie file is also named @file{cookies.txt}, located
967 somewhere under @file{~/.mozilla}, in the directory of your profile.
968 The full path usually ends up looking somewhat like
969 @file{~/.mozilla/default/@var{some-weird-string}/cookies.txt}.
971 @item Internet Explorer.
972 You can produce a cookie file Wget can use by using the File menu,
973 Import and Export, Export Cookies. This has been tested with Internet
974 Explorer 5; it is not guaranteed to work with earlier versions.
976 @item Other browsers.
977 If you are using a different browser to create your cookies,
978 @samp{--load-cookies} will only work if you can locate or produce a
979 cookie file in the Netscape format that Wget expects.
982 If you cannot use @samp{--load-cookies}, there might still be an
983 alternative. If your browser supports a ``cookie manager'', you can use
984 it to view the cookies used when accessing the site you're mirroring.
985 Write down the name and value of the cookie, and manually instruct Wget
986 to send those cookies, bypassing the ``official'' cookie support:
989 wget --cookies=off --header "Cookie: @var{name}=@var{value}"
992 @cindex saving cookies
993 @cindex cookies, saving
994 @item --save-cookies @var{file}
995 Save cookies from @var{file} at the end of session. Cookies whose
996 expiry time is not specified, or those that have already expired, are
999 @cindex Content-Length, ignore
1000 @cindex ignore length
1001 @item --ignore-length
1002 Unfortunately, some @sc{http} servers (@sc{cgi} programs, to be more
1003 precise) send out bogus @code{Content-Length} headers, which makes Wget
1004 go wild, as it thinks not all the document was retrieved. You can spot
1005 this syndrome if Wget retries getting the same document again and again,
1006 each time claiming that the (otherwise normal) connection has closed on
1009 With this option, Wget will ignore the @code{Content-Length} header---as
1010 if it never existed.
1013 @item --header=@var{additional-header}
1014 Define an @var{additional-header} to be passed to the @sc{http} servers.
1015 Headers must contain a @samp{:} preceded by one or more non-blank
1016 characters, and must not contain newlines.
1018 You may define more than one additional header by specifying
1019 @samp{--header} more than once.
1023 wget --header='Accept-Charset: iso-8859-2' \
1024 --header='Accept-Language: hr' \
1025 http://fly.srk.fer.hr/
1029 Specification of an empty string as the header value will clear all
1030 previous user-defined headers.
1033 @cindex proxy password
1034 @cindex proxy authentication
1035 @item --proxy-user=@var{user}
1036 @itemx --proxy-passwd=@var{password}
1037 Specify the username @var{user} and password @var{password} for
1038 authentication on a proxy server. Wget will encode them using the
1039 @code{basic} authentication scheme.
1041 Security considerations similar to those with @samp{--http-passwd}
1042 pertain here as well.
1044 @cindex http referer
1045 @cindex referer, http
1046 @item --referer=@var{url}
1047 Include `Referer: @var{url}' header in HTTP request. Useful for
1048 retrieving documents with server-side processing that assume they are
1049 always being retrieved by interactive web browsers and only come out
1050 properly when Referer is set to one of the pages that point to them.
1052 @cindex server response, save
1054 @itemx --save-headers
1055 Save the headers sent by the @sc{http} server to the file, preceding the
1056 actual contents, with an empty line as the separator.
1059 @item -U @var{agent-string}
1060 @itemx --user-agent=@var{agent-string}
1061 Identify as @var{agent-string} to the @sc{http} server.
1063 The @sc{http} protocol allows the clients to identify themselves using a
1064 @code{User-Agent} header field. This enables distinguishing the
1065 @sc{www} software, usually for statistical purposes or for tracing of
1066 protocol violations. Wget normally identifies as
1067 @samp{Wget/@var{version}}, @var{version} being the current version
1070 However, some sites have been known to impose the policy of tailoring
1071 the output according to the @code{User-Agent}-supplied information.
1072 While conceptually this is not such a bad idea, it has been abused by
1073 servers denying information to clients other than @code{Mozilla} or
1074 Microsoft @code{Internet Explorer}. This option allows you to change
1075 the @code{User-Agent} line issued by Wget. Use of this option is
1076 discouraged, unless you really know what you are doing.
1079 @node FTP Options, Recursive Retrieval Options, HTTP Options, Invoking
1080 @section FTP Options
1083 @cindex .listing files, removing
1085 @itemx --dont-remove-listing
1086 Don't remove the temporary @file{.listing} files generated by @sc{ftp}
1087 retrievals. Normally, these files contain the raw directory listings
1088 received from @sc{ftp} servers. Not removing them can be useful for
1089 debugging purposes, or when you want to be able to easily check on the
1090 contents of remote server directories (e.g. to verify that a mirror
1091 you're running is complete).
1093 Note that even though Wget writes to a known filename for this file,
1094 this is not a security hole in the scenario of a user making
1095 @file{.listing} a symbolic link to @file{/etc/passwd} or something and
1096 asking @code{root} to run Wget in his or her directory. Depending on
1097 the options used, either Wget will refuse to write to @file{.listing},
1098 making the globbing/recursion/time-stamping operation fail, or the
1099 symbolic link will be deleted and replaced with the actual
1100 @file{.listing} file, or the listing will be written to a
1101 @file{.listing.@var{number}} file.
1103 Even though this situation isn't a problem, though, @code{root} should
1104 never run Wget in a non-trusted user's directory. A user could do
1105 something as simple as linking @file{index.html} to @file{/etc/passwd}
1106 and asking @code{root} to run Wget with @samp{-N} or @samp{-r} so the file
1107 will be overwritten.
1109 @cindex globbing, toggle
1111 @itemx --glob=on/off
1112 Turn @sc{ftp} globbing on or off. Globbing means you may use the
1113 shell-like special characters (@dfn{wildcards}), like @samp{*},
1114 @samp{?}, @samp{[} and @samp{]} to retrieve more than one file from the
1115 same directory at once, like:
1118 wget ftp://gnjilux.srk.fer.hr/*.msg
1121 By default, globbing will be turned on if the @sc{url} contains a
1122 globbing character. This option may be used to turn globbing on or off
1125 You may have to quote the @sc{url} to protect it from being expanded by
1126 your shell. Globbing makes Wget look for a directory listing, which is
1127 system-specific. This is why it currently works only with Unix @sc{ftp}
1128 servers (and the ones emulating Unix @code{ls} output).
1132 Use the @dfn{passive} @sc{ftp} retrieval scheme, in which the client
1133 initiates the data connection. This is sometimes required for @sc{ftp}
1134 to work behind firewalls.
1136 @cindex symbolic links, retrieving
1137 @item --retr-symlinks
1138 Usually, when retrieving @sc{ftp} directories recursively and a symbolic
1139 link is encountered, the linked-to file is not downloaded. Instead, a
1140 matching symbolic link is created on the local filesystem. The
1141 pointed-to file will not be downloaded unless this recursive retrieval
1142 would have encountered it separately and downloaded it anyway.
1144 When @samp{--retr-symlinks} is specified, however, symbolic links are
1145 traversed and the pointed-to files are retrieved. At this time, this
1146 option does not cause Wget to traverse symlinks to directories and
1147 recurse through them, but in the future it should be enhanced to do
1150 Note that when retrieving a file (not a directory) because it was
1151 specified on the commandline, rather than because it was recursed to,
1152 this option has no effect. Symbolic links are always traversed in this
1156 @node Recursive Retrieval Options, Recursive Accept/Reject Options, FTP Options, Invoking
1157 @section Recursive Retrieval Options
1162 Turn on recursive retrieving. @xref{Recursive Retrieval}, for more
1165 @item -l @var{depth}
1166 @itemx --level=@var{depth}
1167 Specify recursion maximum depth level @var{depth} (@pxref{Recursive
1168 Retrieval}). The default maximum depth is 5.
1170 @cindex proxy filling
1171 @cindex delete after retrieval
1172 @cindex filling proxy cache
1173 @item --delete-after
1174 This option tells Wget to delete every single file it downloads,
1175 @emph{after} having done so. It is useful for pre-fetching popular
1176 pages through a proxy, e.g.:
1179 wget -r -nd --delete-after http://whatever.com/~popular/page/
1182 The @samp{-r} option is to retrieve recursively, and @samp{-nd} to not
1185 Note that @samp{--delete-after} deletes files on the local machine. It
1186 does not issue the @samp{DELE} command to remote FTP sites, for
1187 instance. Also note that when @samp{--delete-after} is specified,
1188 @samp{--convert-links} is ignored, so @samp{.orig} files are simply not
1189 created in the first place.
1191 @cindex conversion of links
1192 @cindex link conversion
1194 @itemx --convert-links
1195 After the download is complete, convert the links in the document to
1196 make them suitable for local viewing. This affects not only the visible
1197 hyperlinks, but any part of the document that links to external content,
1198 such as embedded images, links to style sheets, hyperlinks to non-HTML
1201 Each link will be changed in one of the two ways:
1205 The links to files that have been downloaded by Wget will be changed to
1206 refer to the file they point to as a relative link.
1208 Example: if the downloaded file @file{/foo/doc.html} links to
1209 @file{/bar/img.gif}, also downloaded, then the link in @file{doc.html}
1210 will be modified to point to @samp{../bar/img.gif}. This kind of
1211 transformation works reliably for arbitrary combinations of directories.
1214 The links to files that have not been downloaded by Wget will be changed
1215 to include host name and absolute path of the location they point to.
1217 Example: if the downloaded file @file{/foo/doc.html} links to
1218 @file{/bar/img.gif} (or to @file{../bar/img.gif}), then the link in
1219 @file{doc.html} will be modified to point to
1220 @file{http://@var{hostname}/bar/img.gif}.
1223 Because of this, local browsing works reliably: if a linked file was
1224 downloaded, the link will refer to its local name; if it was not
1225 downloaded, the link will refer to its full Internet address rather than
1226 presenting a broken link. The fact that the former links are converted
1227 to relative links ensures that you can move the downloaded hierarchy to
1230 Note that only at the end of the download can Wget know which links have
1231 been downloaded. Because of that, the work done by @samp{-k} will be
1232 performed at the end of all the downloads.
1234 @cindex backing up converted files
1236 @itemx --backup-converted
1237 When converting a file, back up the original version with a @samp{.orig}
1238 suffix. Affects the behavior of @samp{-N} (@pxref{HTTP Time-Stamping
1243 Turn on options suitable for mirroring. This option turns on recursion
1244 and time-stamping, sets infinite recursion depth and keeps @sc{ftp}
1245 directory listings. It is currently equivalent to
1246 @samp{-r -N -l inf -nr}.
1248 @cindex page requisites
1249 @cindex required images, downloading
1251 @itemx --page-requisites
1252 This option causes Wget to download all the files that are necessary to
1253 properly display a given HTML page. This includes such things as
1254 inlined images, sounds, and referenced stylesheets.
1256 Ordinarily, when downloading a single HTML page, any requisite documents
1257 that may be needed to display it properly are not downloaded. Using
1258 @samp{-r} together with @samp{-l} can help, but since Wget does not
1259 ordinarily distinguish between external and inlined documents, one is
1260 generally left with ``leaf documents'' that are missing their
1263 For instance, say document @file{1.html} contains an @code{<IMG>} tag
1264 referencing @file{1.gif} and an @code{<A>} tag pointing to external
1265 document @file{2.html}. Say that @file{2.html} is similar but that its
1266 image is @file{2.gif} and it links to @file{3.html}. Say this
1267 continues up to some arbitrarily high number.
1269 If one executes the command:
1272 wget -r -l 2 http://@var{site}/1.html
1275 then @file{1.html}, @file{1.gif}, @file{2.html}, @file{2.gif}, and
1276 @file{3.html} will be downloaded. As you can see, @file{3.html} is
1277 without its requisite @file{3.gif} because Wget is simply counting the
1278 number of hops (up to 2) away from @file{1.html} in order to determine
1279 where to stop the recursion. However, with this command:
1282 wget -r -l 2 -p http://@var{site}/1.html
1285 all the above files @emph{and} @file{3.html}'s requisite @file{3.gif}
1286 will be downloaded. Similarly,
1289 wget -r -l 1 -p http://@var{site}/1.html
1292 will cause @file{1.html}, @file{1.gif}, @file{2.html}, and @file{2.gif}
1293 to be downloaded. One might think that:
1296 wget -r -l 0 -p http://@var{site}/1.html
1299 would download just @file{1.html} and @file{1.gif}, but unfortunately
1300 this is not the case, because @samp{-l 0} is equivalent to
1301 @samp{-l inf}---that is, infinite recursion. To download a single HTML
1302 page (or a handful of them, all specified on the commandline or in a
1303 @samp{-i} @sc{url} input file) and its (or their) requisites, simply leave off
1304 @samp{-r} and @samp{-l}:
1307 wget -p http://@var{site}/1.html
1310 Note that Wget will behave as if @samp{-r} had been specified, but only
1311 that single page and its requisites will be downloaded. Links from that
1312 page to external documents will not be followed. Actually, to download
1313 a single page and all its requisites (even if they exist on separate
1314 websites), and make sure the lot displays properly locally, this author
1315 likes to use a few options in addition to @samp{-p}:
1318 wget -E -H -k -K -p http://@var{site}/@var{document}
1321 To finish off this topic, it's worth knowing that Wget's idea of an
1322 external document link is any URL specified in an @code{<A>} tag, an
1323 @code{<AREA>} tag, or a @code{<LINK>} tag other than @code{<LINK
1327 @node Recursive Accept/Reject Options, , Recursive Retrieval Options, Invoking
1328 @section Recursive Accept/Reject Options
1331 @item -A @var{acclist} --accept @var{acclist}
1332 @itemx -R @var{rejlist} --reject @var{rejlist}
1333 Specify comma-separated lists of file name suffixes or patterns to
1334 accept or reject (@pxref{Types of Files} for more details).
1336 @item -D @var{domain-list}
1337 @itemx --domains=@var{domain-list}
1338 Set domains to be followed. @var{domain-list} is a comma-separated list
1339 of domains. Note that it does @emph{not} turn on @samp{-H}.
1341 @item --exclude-domains @var{domain-list}
1342 Specify the domains that are @emph{not} to be followed.
1343 (@pxref{Spanning Hosts}).
1345 @cindex follow FTP links
1347 Follow @sc{ftp} links from @sc{html} documents. Without this option,
1348 Wget will ignore all the @sc{ftp} links.
1350 @cindex tag-based recursive pruning
1351 @item --follow-tags=@var{list}
1352 Wget has an internal table of HTML tag / attribute pairs that it
1353 considers when looking for linked documents during a recursive
1354 retrieval. If a user wants only a subset of those tags to be
1355 considered, however, he or she should be specify such tags in a
1356 comma-separated @var{list} with this option.
1359 @itemx --ignore-tags=@var{list}
1360 This is the opposite of the @samp{--follow-tags} option. To skip
1361 certain HTML tags when recursively looking for documents to download,
1362 specify them in a comma-separated @var{list}.
1364 In the past, the @samp{-G} option was the best bet for downloading a
1365 single page and its requisites, using a commandline like:
1368 wget -Ga,area -H -k -K -r http://@var{site}/@var{document}
1371 However, the author of this option came across a page with tags like
1372 @code{<LINK REL="home" HREF="/">} and came to the realization that
1373 @samp{-G} was not enough. One can't just tell Wget to ignore
1374 @code{<LINK>}, because then stylesheets will not be downloaded. Now the
1375 best bet for downloading a single page and its requisites is the
1376 dedicated @samp{--page-requisites} option.
1380 Enable spanning across hosts when doing recursive retrieving
1381 (@pxref{Spanning Hosts}).
1385 Follow relative links only. Useful for retrieving a specific home page
1386 without any distractions, not even those from the same hosts
1387 (@pxref{Relative Links}).
1390 @itemx --include-directories=@var{list}
1391 Specify a comma-separated list of directories you wish to follow when
1392 downloading (@pxref{Directory-Based Limits} for more details.) Elements
1393 of @var{list} may contain wildcards.
1396 @itemx --exclude-directories=@var{list}
1397 Specify a comma-separated list of directories you wish to exclude from
1398 download (@pxref{Directory-Based Limits} for more details.) Elements of
1399 @var{list} may contain wildcards.
1403 Do not ever ascend to the parent directory when retrieving recursively.
1404 This is a useful option, since it guarantees that only the files
1405 @emph{below} a certain hierarchy will be downloaded.
1406 @xref{Directory-Based Limits}, for more details.
1411 @node Recursive Retrieval, Following Links, Invoking, Top
1412 @chapter Recursive Retrieval
1415 @cindex recursive retrieval
1417 GNU Wget is capable of traversing parts of the Web (or a single
1418 @sc{http} or @sc{ftp} server), following links and directory structure.
1419 We refer to this as to @dfn{recursive retrieving}, or @dfn{recursion}.
1421 With @sc{http} @sc{url}s, Wget retrieves and parses the @sc{html} from
1422 the given @sc{url}, documents, retrieving the files the @sc{html}
1423 document was referring to, through markups like @code{href}, or
1424 @code{src}. If the freshly downloaded file is also of type
1425 @code{text/html}, it will be parsed and followed further.
1427 Recursive retrieval of @sc{http} and @sc{html} content is
1428 @dfn{breadth-first}. This means that Wget first downloads the requested
1429 HTML document, then the documents linked from that document, then the
1430 documents linked by them, and so on. In other words, Wget first
1431 downloads the documents at depth 1, then those at depth 2, and so on
1432 until the specified maximum depth.
1434 The maximum @dfn{depth} to which the retrieval may descend is specified
1435 with the @samp{-l} option. The default maximum depth is five layers.
1437 When retrieving an @sc{ftp} @sc{url} recursively, Wget will retrieve all
1438 the data from the given directory tree (including the subdirectories up
1439 to the specified depth) on the remote server, creating its mirror image
1440 locally. @sc{ftp} retrieval is also limited by the @code{depth}
1441 parameter. Unlike @sc{http} recursion, @sc{ftp} recursion is performed
1444 By default, Wget will create a local directory tree, corresponding to
1445 the one found on the remote server.
1447 Recursive retrieving can find a number of applications, the most
1448 important of which is mirroring. It is also useful for @sc{www}
1449 presentations, and any other opportunities where slow network
1450 connections should be bypassed by storing the files locally.
1452 You should be warned that recursive downloads can overload the remote
1453 servers. Because of that, many administrators frown upon them and may
1454 ban access from your site if they detect very fast downloads of big
1455 amounts of content. When downloading from Internet servers, consider
1456 using the @samp{-w} option to introduce a delay between accesses to the
1457 server. The download will take a while longer, but the server
1458 administrator will not be alarmed by your rudeness.
1460 Of course, recursive download may cause problems on your machine. If
1461 left to run unchecked, it can easily fill up the disk. If downloading
1462 from local network, it can also take bandwidth on the system, as well as
1463 consume memory and CPU.
1465 Try to specify the criteria that match the kind of download you are
1466 trying to achieve. If you want to download only one page, use
1467 @samp{--page-requisites} without any additional recursion. If you want
1468 to download things under one directory, use @samp{-np} to avoid
1469 downloading things from other directories. If you want to download all
1470 the files from one directory, use @samp{-l 1} to make sure the recursion
1471 depth never exceeds one. @xref{Following Links}, for more information
1474 Recursive retrieval should be used with care. Don't say you were not
1477 @node Following Links, Time-Stamping, Recursive Retrieval, Top
1478 @chapter Following Links
1480 @cindex following links
1482 When retrieving recursively, one does not wish to retrieve loads of
1483 unnecessary data. Most of the time the users bear in mind exactly what
1484 they want to download, and want Wget to follow only specific links.
1486 For example, if you wish to download the music archive from
1487 @samp{fly.srk.fer.hr}, you will not want to download all the home pages
1488 that happen to be referenced by an obscure part of the archive.
1490 Wget possesses several mechanisms that allows you to fine-tune which
1491 links it will follow.
1494 * Spanning Hosts:: (Un)limiting retrieval based on host name.
1495 * Types of Files:: Getting only certain files.
1496 * Directory-Based Limits:: Getting only certain directories.
1497 * Relative Links:: Follow relative links only.
1498 * FTP Links:: Following FTP links.
1501 @node Spanning Hosts, Types of Files, Following Links, Following Links
1502 @section Spanning Hosts
1503 @cindex spanning hosts
1504 @cindex hosts, spanning
1506 Wget's recursive retrieval normally refuses to visit hosts different
1507 than the one you specified on the command line. This is a reasonable
1508 default; without it, every retrieval would have the potential to turn
1509 your Wget into a small version of google.
1511 However, visiting different hosts, or @dfn{host spanning,} is sometimes
1512 a useful option. Maybe the images are served from a different server.
1513 Maybe you're mirroring a site that consists of pages interlinked between
1514 three servers. Maybe the server has two equivalent names, and the HTML
1515 pages refer to both interchangeably.
1518 @item Span to any host---@samp{-H}
1520 The @samp{-H} option turns on host spanning, thus allowing Wget's
1521 recursive run to visit any host referenced by a link. Unless sufficient
1522 recursion-limiting criteria are applied depth, these foreign hosts will
1523 typically link to yet more hosts, and so on until Wget ends up sucking
1524 up much more data than you have intended.
1526 @item Limit spanning to certain domains---@samp{-D}
1528 The @samp{-D} option allows you to specify the domains that will be
1529 followed, thus limiting the recursion only to the hosts that belong to
1530 these domains. Obviously, this makes sense only in conjunction with
1531 @samp{-H}. A typical example would be downloading the contents of
1532 @samp{www.server.com}, but allowing downloads from
1533 @samp{images.server.com}, etc.:
1536 wget -rH -Dserver.com http://www.server.com/
1539 You can specify more than one address by separating them with a comma,
1540 e.g. @samp{-Ddomain1.com,domain2.com}.
1542 @item Keep download off certain domains---@samp{--exclude-domains}
1544 If there are domains you want to exclude specifically, you can do it
1545 with @samp{--exclude-domains}, which accepts the same type of arguments
1546 of @samp{-D}, but will @emph{exclude} all the listed domains. For
1547 example, if you want to download all the hosts from @samp{foo.edu}
1548 domain, with the exception of @samp{sunsite.foo.edu}, you can do it like
1552 wget -rH -Dfoo.edu --exclude-domains sunsite.foo.edu \
1558 @node Types of Files, Directory-Based Limits, Spanning Hosts, Following Links
1559 @section Types of Files
1560 @cindex types of files
1562 When downloading material from the web, you will often want to restrict
1563 the retrieval to only certain file types. For example, if you are
1564 interested in downloading @sc{gif}s, you will not be overjoyed to get
1565 loads of PostScript documents, and vice versa.
1567 Wget offers two options to deal with this problem. Each option
1568 description lists a short name, a long name, and the equivalent command
1571 @cindex accept wildcards
1572 @cindex accept suffixes
1573 @cindex wildcards, accept
1574 @cindex suffixes, accept
1576 @item -A @var{acclist}
1577 @itemx --accept @var{acclist}
1578 @itemx accept = @var{acclist}
1579 The argument to @samp{--accept} option is a list of file suffixes or
1580 patterns that Wget will download during recursive retrieval. A suffix
1581 is the ending part of a file, and consists of ``normal'' letters,
1582 e.g. @samp{gif} or @samp{.jpg}. A matching pattern contains shell-like
1583 wildcards, e.g. @samp{books*} or @samp{zelazny*196[0-9]*}.
1585 So, specifying @samp{wget -A gif,jpg} will make Wget download only the
1586 files ending with @samp{gif} or @samp{jpg}, i.e. @sc{gif}s and
1587 @sc{jpeg}s. On the other hand, @samp{wget -A "zelazny*196[0-9]*"} will
1588 download only files beginning with @samp{zelazny} and containing numbers
1589 from 1960 to 1969 anywhere within. Look up the manual of your shell for
1590 a description of how pattern matching works.
1592 Of course, any number of suffixes and patterns can be combined into a
1593 comma-separated list, and given as an argument to @samp{-A}.
1595 @cindex reject wildcards
1596 @cindex reject suffixes
1597 @cindex wildcards, reject
1598 @cindex suffixes, reject
1599 @item -R @var{rejlist}
1600 @itemx --reject @var{rejlist}
1601 @itemx reject = @var{rejlist}
1602 The @samp{--reject} option works the same way as @samp{--accept}, only
1603 its logic is the reverse; Wget will download all files @emph{except} the
1604 ones matching the suffixes (or patterns) in the list.
1606 So, if you want to download a whole page except for the cumbersome
1607 @sc{mpeg}s and @sc{.au} files, you can use @samp{wget -R mpg,mpeg,au}.
1608 Analogously, to download all files except the ones beginning with
1609 @samp{bjork}, use @samp{wget -R "bjork*"}. The quotes are to prevent
1610 expansion by the shell.
1613 The @samp{-A} and @samp{-R} options may be combined to achieve even
1614 better fine-tuning of which files to retrieve. E.g. @samp{wget -A
1615 "*zelazny*" -R .ps} will download all the files having @samp{zelazny} as
1616 a part of their name, but @emph{not} the PostScript files.
1618 Note that these two options do not affect the downloading of @sc{html}
1619 files; Wget must load all the @sc{html}s to know where to go at
1620 all---recursive retrieval would make no sense otherwise.
1622 @node Directory-Based Limits, Relative Links, Types of Files, Following Links
1623 @section Directory-Based Limits
1625 @cindex directory limits
1627 Regardless of other link-following facilities, it is often useful to
1628 place the restriction of what files to retrieve based on the directories
1629 those files are placed in. There can be many reasons for this---the
1630 home pages may be organized in a reasonable directory structure; or some
1631 directories may contain useless information, e.g. @file{/cgi-bin} or
1632 @file{/dev} directories.
1634 Wget offers three different options to deal with this requirement. Each
1635 option description lists a short name, a long name, and the equivalent
1636 command in @file{.wgetrc}.
1638 @cindex directories, include
1639 @cindex include directories
1640 @cindex accept directories
1643 @itemx --include @var{list}
1644 @itemx include_directories = @var{list}
1645 @samp{-I} option accepts a comma-separated list of directories included
1646 in the retrieval. Any other directories will simply be ignored. The
1647 directories are absolute paths.
1649 So, if you wish to download from @samp{http://host/people/bozo/}
1650 following only links to bozo's colleagues in the @file{/people}
1651 directory and the bogus scripts in @file{/cgi-bin}, you can specify:
1654 wget -I /people,/cgi-bin http://host/people/bozo/
1657 @cindex directories, exclude
1658 @cindex exclude directories
1659 @cindex reject directories
1661 @itemx --exclude @var{list}
1662 @itemx exclude_directories = @var{list}
1663 @samp{-X} option is exactly the reverse of @samp{-I}---this is a list of
1664 directories @emph{excluded} from the download. E.g. if you do not want
1665 Wget to download things from @file{/cgi-bin} directory, specify @samp{-X
1666 /cgi-bin} on the command line.
1668 The same as with @samp{-A}/@samp{-R}, these two options can be combined
1669 to get a better fine-tuning of downloading subdirectories. E.g. if you
1670 want to load all the files from @file{/pub} hierarchy except for
1671 @file{/pub/worthless}, specify @samp{-I/pub -X/pub/worthless}.
1676 @itemx no_parent = on
1677 The simplest, and often very useful way of limiting directories is
1678 disallowing retrieval of the links that refer to the hierarchy
1679 @dfn{above} than the beginning directory, i.e. disallowing ascent to the
1680 parent directory/directories.
1682 The @samp{--no-parent} option (short @samp{-np}) is useful in this case.
1683 Using it guarantees that you will never leave the existing hierarchy.
1684 Supposing you issue Wget with:
1687 wget -r --no-parent http://somehost/~luzer/my-archive/
1690 You may rest assured that none of the references to
1691 @file{/~his-girls-homepage/} or @file{/~luzer/all-my-mpegs/} will be
1692 followed. Only the archive you are interested in will be downloaded.
1693 Essentially, @samp{--no-parent} is similar to
1694 @samp{-I/~luzer/my-archive}, only it handles redirections in a more
1695 intelligent fashion.
1698 @node Relative Links, FTP Links, Directory-Based Limits, Following Links
1699 @section Relative Links
1700 @cindex relative links
1702 When @samp{-L} is turned on, only the relative links are ever followed.
1703 Relative links are here defined those that do not refer to the web
1704 server root. For example, these links are relative:
1708 <a href="foo/bar.gif">
1709 <a href="../foo/bar.gif">
1712 These links are not relative:
1716 <a href="/foo/bar.gif">
1717 <a href="http://www.server.com/foo/bar.gif">
1720 Using this option guarantees that recursive retrieval will not span
1721 hosts, even without @samp{-H}. In simple cases it also allows downloads
1722 to ``just work'' without having to convert links.
1724 This option is probably not very useful and might be removed in a future
1727 @node FTP Links, , Relative Links, Following Links
1728 @section Following FTP Links
1729 @cindex following ftp links
1731 The rules for @sc{ftp} are somewhat specific, as it is necessary for
1732 them to be. @sc{ftp} links in @sc{html} documents are often included
1733 for purposes of reference, and it is often inconvenient to download them
1736 To have @sc{ftp} links followed from @sc{html} documents, you need to
1737 specify the @samp{--follow-ftp} option. Having done that, @sc{ftp}
1738 links will span hosts regardless of @samp{-H} setting. This is logical,
1739 as @sc{ftp} links rarely point to the same host where the @sc{http}
1740 server resides. For similar reasons, the @samp{-L} options has no
1741 effect on such downloads. On the other hand, domain acceptance
1742 (@samp{-D}) and suffix rules (@samp{-A} and @samp{-R}) apply normally.
1744 Also note that followed links to @sc{ftp} directories will not be
1745 retrieved recursively further.
1747 @node Time-Stamping, Startup File, Following Links, Top
1748 @chapter Time-Stamping
1749 @cindex time-stamping
1750 @cindex timestamping
1751 @cindex updating the archives
1752 @cindex incremental updating
1754 One of the most important aspects of mirroring information from the
1755 Internet is updating your archives.
1757 Downloading the whole archive again and again, just to replace a few
1758 changed files is expensive, both in terms of wasted bandwidth and money,
1759 and the time to do the update. This is why all the mirroring tools
1760 offer the option of incremental updating.
1762 Such an updating mechanism means that the remote server is scanned in
1763 search of @dfn{new} files. Only those new files will be downloaded in
1764 the place of the old ones.
1766 A file is considered new if one of these two conditions are met:
1770 A file of that name does not already exist locally.
1773 A file of that name does exist, but the remote file was modified more
1774 recently than the local file.
1777 To implement this, the program needs to be aware of the time of last
1778 modification of both local and remote files. We call this information the
1779 @dfn{time-stamp} of a file.
1781 The time-stamping in GNU Wget is turned on using @samp{--timestamping}
1782 (@samp{-N}) option, or through @code{timestamping = on} directive in
1783 @file{.wgetrc}. With this option, for each file it intends to download,
1784 Wget will check whether a local file of the same name exists. If it
1785 does, and the remote file is older, Wget will not download it.
1787 If the local file does not exist, or the sizes of the files do not
1788 match, Wget will download the remote file no matter what the time-stamps
1792 * Time-Stamping Usage::
1793 * HTTP Time-Stamping Internals::
1794 * FTP Time-Stamping Internals::
1797 @node Time-Stamping Usage, HTTP Time-Stamping Internals, Time-Stamping, Time-Stamping
1798 @section Time-Stamping Usage
1799 @cindex time-stamping usage
1800 @cindex usage, time-stamping
1802 The usage of time-stamping is simple. Say you would like to download a
1803 file so that it keeps its date of modification.
1806 wget -S http://www.gnu.ai.mit.edu/
1809 A simple @code{ls -l} shows that the time stamp on the local file equals
1810 the state of the @code{Last-Modified} header, as returned by the server.
1811 As you can see, the time-stamping info is preserved locally, even
1812 without @samp{-N} (at least for @sc{http}).
1814 Several days later, you would like Wget to check if the remote file has
1815 changed, and download it if it has.
1818 wget -N http://www.gnu.ai.mit.edu/
1821 Wget will ask the server for the last-modified date. If the local file
1822 has the same timestamp as the server, or a newer one, the remote file
1823 will not be re-fetched. However, if the remote file is more recent,
1824 Wget will proceed to fetch it.
1826 The same goes for @sc{ftp}. For example:
1829 wget "ftp://ftp.ifi.uio.no/pub/emacs/gnus/*"
1832 (The quotes around that URL are to prevent the shell from trying to
1833 interpret the @samp{*}.)
1835 After download, a local directory listing will show that the timestamps
1836 match those on the remote server. Reissuing the command with @samp{-N}
1837 will make Wget re-fetch @emph{only} the files that have been modified
1838 since the last download.
1840 If you wished to mirror the GNU archive every week, you would use a
1841 command like the following, weekly:
1844 wget --timestamping -r ftp://ftp.gnu.org/pub/gnu/
1847 Note that time-stamping will only work for files for which the server
1848 gives a timestamp. For @sc{http}, this depends on getting a
1849 @code{Last-Modified} header. For @sc{ftp}, this depends on getting a
1850 directory listing with dates in a format that Wget can parse
1851 (@pxref{FTP Time-Stamping Internals}).
1853 @node HTTP Time-Stamping Internals, FTP Time-Stamping Internals, Time-Stamping Usage, Time-Stamping
1854 @section HTTP Time-Stamping Internals
1855 @cindex http time-stamping
1857 Time-stamping in @sc{http} is implemented by checking of the
1858 @code{Last-Modified} header. If you wish to retrieve the file
1859 @file{foo.html} through @sc{http}, Wget will check whether
1860 @file{foo.html} exists locally. If it doesn't, @file{foo.html} will be
1861 retrieved unconditionally.
1863 If the file does exist locally, Wget will first check its local
1864 time-stamp (similar to the way @code{ls -l} checks it), and then send a
1865 @code{HEAD} request to the remote server, demanding the information on
1868 The @code{Last-Modified} header is examined to find which file was
1869 modified more recently (which makes it ``newer''). If the remote file
1870 is newer, it will be downloaded; if it is older, Wget will give
1871 up.@footnote{As an additional check, Wget will look at the
1872 @code{Content-Length} header, and compare the sizes; if they are not the
1873 same, the remote file will be downloaded no matter what the time-stamp
1876 When @samp{--backup-converted} (@samp{-K}) is specified in conjunction
1877 with @samp{-N}, server file @samp{@var{X}} is compared to local file
1878 @samp{@var{X}.orig}, if extant, rather than being compared to local file
1879 @samp{@var{X}}, which will always differ if it's been converted by
1880 @samp{--convert-links} (@samp{-k}).
1882 Arguably, @sc{http} time-stamping should be implemented using the
1883 @code{If-Modified-Since} request.
1885 @node FTP Time-Stamping Internals, , HTTP Time-Stamping Internals, Time-Stamping
1886 @section FTP Time-Stamping Internals
1887 @cindex ftp time-stamping
1889 In theory, @sc{ftp} time-stamping works much the same as @sc{http}, only
1890 @sc{ftp} has no headers---time-stamps must be ferreted out of directory
1893 If an @sc{ftp} download is recursive or uses globbing, Wget will use the
1894 @sc{ftp} @code{LIST} command to get a file listing for the directory
1895 containing the desired file(s). It will try to analyze the listing,
1896 treating it like Unix @code{ls -l} output, extracting the time-stamps.
1897 The rest is exactly the same as for @sc{http}. Note that when
1898 retrieving individual files from an @sc{ftp} server without using
1899 globbing or recursion, listing files will not be downloaded (and thus
1900 files will not be time-stamped) unless @samp{-N} is specified.
1902 Assumption that every directory listing is a Unix-style listing may
1903 sound extremely constraining, but in practice it is not, as many
1904 non-Unix @sc{ftp} servers use the Unixoid listing format because most
1905 (all?) of the clients understand it. Bear in mind that @sc{rfc959}
1906 defines no standard way to get a file list, let alone the time-stamps.
1907 We can only hope that a future standard will define this.
1909 Another non-standard solution includes the use of @code{MDTM} command
1910 that is supported by some @sc{ftp} servers (including the popular
1911 @code{wu-ftpd}), which returns the exact time of the specified file.
1912 Wget may support this command in the future.
1914 @node Startup File, Examples, Time-Stamping, Top
1915 @chapter Startup File
1916 @cindex startup file
1922 Once you know how to change default settings of Wget through command
1923 line arguments, you may wish to make some of those settings permanent.
1924 You can do that in a convenient way by creating the Wget startup
1925 file---@file{.wgetrc}.
1927 Besides @file{.wgetrc} is the ``main'' initialization file, it is
1928 convenient to have a special facility for storing passwords. Thus Wget
1929 reads and interprets the contents of @file{$HOME/.netrc}, if it finds
1930 it. You can find @file{.netrc} format in your system manuals.
1932 Wget reads @file{.wgetrc} upon startup, recognizing a limited set of
1936 * Wgetrc Location:: Location of various wgetrc files.
1937 * Wgetrc Syntax:: Syntax of wgetrc.
1938 * Wgetrc Commands:: List of available commands.
1939 * Sample Wgetrc:: A wgetrc example.
1942 @node Wgetrc Location, Wgetrc Syntax, Startup File, Startup File
1943 @section Wgetrc Location
1944 @cindex wgetrc location
1945 @cindex location of wgetrc
1947 When initializing, Wget will look for a @dfn{global} startup file,
1948 @file{/usr/local/etc/wgetrc} by default (or some prefix other than
1949 @file{/usr/local}, if Wget was not installed there) and read commands
1950 from there, if it exists.
1952 Then it will look for the user's file. If the environmental variable
1953 @code{WGETRC} is set, Wget will try to load that file. Failing that, no
1954 further attempts will be made.
1956 If @code{WGETRC} is not set, Wget will try to load @file{$HOME/.wgetrc}.
1958 The fact that user's settings are loaded after the system-wide ones
1959 means that in case of collision user's wgetrc @emph{overrides} the
1960 system-wide wgetrc (in @file{/usr/local/etc/wgetrc} by default).
1961 Fascist admins, away!
1963 @node Wgetrc Syntax, Wgetrc Commands, Wgetrc Location, Startup File
1964 @section Wgetrc Syntax
1965 @cindex wgetrc syntax
1966 @cindex syntax of wgetrc
1968 The syntax of a wgetrc command is simple:
1974 The @dfn{variable} will also be called @dfn{command}. Valid
1975 @dfn{values} are different for different commands.
1977 The commands are case-insensitive and underscore-insensitive. Thus
1978 @samp{DIr__PrefiX} is the same as @samp{dirprefix}. Empty lines, lines
1979 beginning with @samp{#} and lines containing white-space only are
1982 Commands that expect a comma-separated list will clear the list on an
1983 empty command. So, if you wish to reset the rejection list specified in
1984 global @file{wgetrc}, you can do it with:
1990 @node Wgetrc Commands, Sample Wgetrc, Wgetrc Syntax, Startup File
1991 @section Wgetrc Commands
1992 @cindex wgetrc commands
1994 The complete set of commands is listed below. Legal values are listed
1995 after the @samp{=}. Simple Boolean values can be set or unset using
1996 @samp{on} and @samp{off} or @samp{1} and @samp{0}. A fancier kind of
1997 Boolean allowed in some cases is the @dfn{lockable Boolean}, which may
1998 be set to @samp{on}, @samp{off}, @samp{always}, or @samp{never}. If an
1999 option is set to @samp{always} or @samp{never}, that value will be
2000 locked in for the duration of the Wget invocation---commandline options
2003 Some commands take pseudo-arbitrary values. @var{address} values can be
2004 hostnames or dotted-quad IP addresses. @var{n} can be any positive
2005 integer, or @samp{inf} for infinity, where appropriate. @var{string}
2006 values can be any non-empty string.
2008 Most of these commands have commandline equivalents (@pxref{Invoking}),
2009 though some of the more obscure or rarely used ones do not.
2012 @item accept/reject = @var{string}
2013 Same as @samp{-A}/@samp{-R} (@pxref{Types of Files}).
2015 @item add_hostdir = on/off
2016 Enable/disable host-prefixed file names. @samp{-nH} disables it.
2018 @item continue = on/off
2019 If set to on, force continuation of preexistent partially retrieved
2020 files. See @samp{-c} before setting it.
2022 @item background = on/off
2023 Enable/disable going to background---the same as @samp{-b} (which
2026 @item backup_converted = on/off
2027 Enable/disable saving pre-converted files with the suffix
2028 @samp{.orig}---the same as @samp{-K} (which enables it).
2030 @c @item backups = @var{number}
2031 @c #### Document me!
2033 @item base = @var{string}
2034 Consider relative @sc{url}s in @sc{url} input files forced to be
2035 interpreted as @sc{html} as being relative to @var{string}---the same as
2038 @item bind_address = @var{address}
2039 Bind to @var{address}, like the @samp{--bind-address} option.
2041 @item cache = on/off
2042 When set to off, disallow server-caching. See the @samp{-C} option.
2044 @item convert links = on/off
2045 Convert non-relative links locally. The same as @samp{-k}.
2047 @item cookies = on/off
2048 When set to off, disallow cookies. See the @samp{--cookies} option.
2050 @item load_cookies = @var{file}
2051 Load cookies from @var{file}. See @samp{--load-cookies}.
2053 @item save_cookies = @var{file}
2054 Save cookies to @var{file}. See @samp{--save-cookies}.
2056 @item cut_dirs = @var{n}
2057 Ignore @var{n} remote directory components.
2059 @item debug = on/off
2060 Debug mode, same as @samp{-d}.
2062 @item delete_after = on/off
2063 Delete after download---the same as @samp{--delete-after}.
2065 @item dir_prefix = @var{string}
2066 Top of directory tree---the same as @samp{-P}.
2068 @item dirstruct = on/off
2069 Turning dirstruct on or off---the same as @samp{-x} or @samp{-nd},
2072 @item dns_cache = on/off
2073 Turn DNS caching on/off. Since DNS caching is on by default, this
2074 option is normally used to turn it off. Same as @samp{--dns-cache}.
2076 @item domains = @var{string}
2077 Same as @samp{-D} (@pxref{Spanning Hosts}).
2079 @item dot_bytes = @var{n}
2080 Specify the number of bytes ``contained'' in a dot, as seen throughout
2081 the retrieval (1024 by default). You can postfix the value with
2082 @samp{k} or @samp{m}, representing kilobytes and megabytes,
2083 respectively. With dot settings you can tailor the dot retrieval to
2084 suit your needs, or you can use the predefined @dfn{styles}
2085 (@pxref{Download Options}).
2087 @item dots_in_line = @var{n}
2088 Specify the number of dots that will be printed in each line throughout
2089 the retrieval (50 by default).
2091 @item dot_spacing = @var{n}
2092 Specify the number of dots in a single cluster (10 by default).
2094 @item exclude_directories = @var{string}
2095 Specify a comma-separated list of directories you wish to exclude from
2096 download---the same as @samp{-X} (@pxref{Directory-Based Limits}).
2098 @item exclude_domains = @var{string}
2099 Same as @samp{--exclude-domains} (@pxref{Spanning Hosts}).
2101 @item follow_ftp = on/off
2102 Follow @sc{ftp} links from @sc{html} documents---the same as
2103 @samp{--follow-ftp}.
2105 @item follow_tags = @var{string}
2106 Only follow certain HTML tags when doing a recursive retrieval, just like
2107 @samp{--follow-tags}.
2109 @item force_html = on/off
2110 If set to on, force the input filename to be regarded as an @sc{html}
2111 document---the same as @samp{-F}.
2113 @item ftp_proxy = @var{string}
2114 Use @var{string} as @sc{ftp} proxy, instead of the one specified in
2118 Turn globbing on/off---the same as @samp{-g}.
2120 @item header = @var{string}
2121 Define an additional header, like @samp{--header}.
2123 @item html_extension = on/off
2124 Add a @samp{.html} extension to @samp{text/html} files without it, like
2127 @item http_passwd = @var{string}
2128 Set @sc{http} password.
2130 @item http_proxy = @var{string}
2131 Use @var{string} as @sc{http} proxy, instead of the one specified in
2134 @item http_user = @var{string}
2135 Set @sc{http} user to @var{string}.
2137 @item ignore_length = on/off
2138 When set to on, ignore @code{Content-Length} header; the same as
2139 @samp{--ignore-length}.
2141 @item ignore_tags = @var{string}
2142 Ignore certain HTML tags when doing a recursive retrieval, just like
2143 @samp{-G} / @samp{--ignore-tags}.
2145 @item include_directories = @var{string}
2146 Specify a comma-separated list of directories you wish to follow when
2147 downloading---the same as @samp{-I}.
2149 @item input = @var{string}
2150 Read the @sc{url}s from @var{string}, like @samp{-i}.
2152 @item kill_longer = on/off
2153 Consider data longer than specified in content-length header as invalid
2154 (and retry getting it). The default behaviour is to save as much data
2155 as there is, provided there is more than or equal to the value in
2156 @code{Content-Length}.
2158 @item limit_rate = @var{rate}
2159 Limit the download speed to no more than @var{rate} bytes per second.
2160 The same as @samp{--limit-rate}.
2162 @item logfile = @var{string}
2163 Set logfile---the same as @samp{-o}.
2165 @item login = @var{string}
2166 Your user name on the remote machine, for @sc{ftp}. Defaults to
2169 @item mirror = on/off
2170 Turn mirroring on/off. The same as @samp{-m}.
2172 @item netrc = on/off
2173 Turn reading netrc on or off.
2175 @item noclobber = on/off
2178 @item no_parent = on/off
2179 Disallow retrieving outside the directory hierarchy, like
2180 @samp{--no-parent} (@pxref{Directory-Based Limits}).
2182 @item no_proxy = @var{string}
2183 Use @var{string} as the comma-separated list of domains to avoid in
2184 proxy loading, instead of the one specified in environment.
2186 @item output_document = @var{string}
2187 Set the output filename---the same as @samp{-O}.
2189 @item page_requisites = on/off
2190 Download all ancillary documents necessary for a single HTML page to
2191 display properly---the same as @samp{-p}.
2193 @item passive_ftp = on/off/always/never
2194 Set passive @sc{ftp}---the same as @samp{--passive-ftp}. Some scripts
2195 and @samp{.pm} (Perl module) files download files using @samp{wget
2196 --passive-ftp}. If your firewall does not allow this, you can set
2197 @samp{passive_ftp = never} to override the commandline.
2199 @item passwd = @var{string}
2200 Set your @sc{ftp} password to @var{password}. Without this setting, the
2201 password defaults to @samp{username@@hostname.domainname}.
2203 @item progress = @var{string}
2204 Set the type of the progress indicator. Legal types are ``dot'' and
2207 @item proxy_user = @var{string}
2208 Set proxy authentication user name to @var{string}, like @samp{--proxy-user}.
2210 @item proxy_passwd = @var{string}
2211 Set proxy authentication password to @var{string}, like @samp{--proxy-passwd}.
2213 @item referer = @var{string}
2214 Set HTTP @samp{Referer:} header just like @samp{--referer}. (Note it
2215 was the folks who wrote the @sc{http} spec who got the spelling of
2216 ``referrer'' wrong.)
2218 @item quiet = on/off
2219 Quiet mode---the same as @samp{-q}.
2221 @item quota = @var{quota}
2222 Specify the download quota, which is useful to put in the global
2223 @file{wgetrc}. When download quota is specified, Wget will stop
2224 retrieving after the download sum has become greater than quota. The
2225 quota can be specified in bytes (default), kbytes @samp{k} appended) or
2226 mbytes (@samp{m} appended). Thus @samp{quota = 5m} will set the quota
2227 to 5 mbytes. Note that the user's startup file overrides system
2230 @item reclevel = @var{n}
2231 Recursion level---the same as @samp{-l}.
2233 @item recursive = on/off
2234 Recursive on/off---the same as @samp{-r}.
2236 @item relative_only = on/off
2237 Follow only relative links---the same as @samp{-L} (@pxref{Relative
2240 @item remove_listing = on/off
2241 If set to on, remove @sc{ftp} listings downloaded by Wget. Setting it
2242 to off is the same as @samp{-nr}.
2244 @item retr_symlinks = on/off
2245 When set to on, retrieve symbolic links as if they were plain files; the
2246 same as @samp{--retr-symlinks}.
2248 @item robots = on/off
2249 Specify whether the norobots convention is respected by Wget, ``on'' by
2250 default. This switch controls both the @file{/robots.txt} and the
2251 @samp{nofollow} aspect of the spec. @xref{Robot Exclusion}, for more
2252 details about this. Be sure you know what you are doing before turning
2255 @item server_response = on/off
2256 Choose whether or not to print the @sc{http} and @sc{ftp} server
2257 responses---the same as @samp{-S}.
2259 @item span_hosts = on/off
2262 @item timeout = @var{n}
2263 Set timeout value---the same as @samp{-T}.
2265 @item timestamping = on/off
2266 Turn timestamping on/off. The same as @samp{-N} (@pxref{Time-Stamping}).
2268 @item tries = @var{n}
2269 Set number of retries per @sc{url}---the same as @samp{-t}.
2271 @item use_proxy = on/off
2272 Turn proxy support on/off. The same as @samp{-Y}.
2274 @item verbose = on/off
2275 Turn verbose on/off---the same as @samp{-v}/@samp{-nv}.
2277 @item wait = @var{n}
2278 Wait @var{n} seconds between retrievals---the same as @samp{-w}.
2280 @item waitretry = @var{n}
2281 Wait up to @var{n} seconds between retries of failed retrievals
2282 only---the same as @samp{--waitretry}. Note that this is turned on by
2283 default in the global @file{wgetrc}.
2285 @item randomwait = on/off
2286 Turn random between-request wait times on or off. The same as
2287 @samp{--random-wait}.
2290 @node Sample Wgetrc, , Wgetrc Commands, Startup File
2291 @section Sample Wgetrc
2292 @cindex sample wgetrc
2294 This is the sample initialization file, as given in the distribution.
2295 It is divided in two section---one for global usage (suitable for global
2296 startup file), and one for local usage (suitable for
2297 @file{$HOME/.wgetrc}). Be careful about the things you change.
2299 Note that almost all the lines are commented out. For a command to have
2300 any effect, you must remove the @samp{#} character at the beginning of
2304 @include sample.wgetrc.munged_for_texi_inclusion
2307 @node Examples, Various, Startup File, Top
2311 @c man begin EXAMPLES
2312 The examples are divided into three sections loosely based on their
2316 * Simple Usage:: Simple, basic usage of the program.
2317 * Advanced Usage:: Advanced tips.
2318 * Very Advanced Usage:: The hairy stuff.
2321 @node Simple Usage, Advanced Usage, Examples, Examples
2322 @section Simple Usage
2326 Say you want to download a @sc{url}. Just type:
2329 wget http://fly.srk.fer.hr/
2333 But what will happen if the connection is slow, and the file is lengthy?
2334 The connection will probably fail before the whole file is retrieved,
2335 more than once. In this case, Wget will try getting the file until it
2336 either gets the whole of it, or exceeds the default number of retries
2337 (this being 20). It is easy to change the number of tries to 45, to
2338 insure that the whole file will arrive safely:
2341 wget --tries=45 http://fly.srk.fer.hr/jpg/flyweb.jpg
2345 Now let's leave Wget to work in the background, and write its progress
2346 to log file @file{log}. It is tiring to type @samp{--tries}, so we
2347 shall use @samp{-t}.
2350 wget -t 45 -o log http://fly.srk.fer.hr/jpg/flyweb.jpg &
2353 The ampersand at the end of the line makes sure that Wget works in the
2354 background. To unlimit the number of retries, use @samp{-t inf}.
2357 The usage of @sc{ftp} is as simple. Wget will take care of login and
2361 wget ftp://gnjilux.srk.fer.hr/welcome.msg
2365 If you specify a directory, Wget will retrieve the directory listing,
2366 parse it and convert it to @sc{html}. Try:
2369 wget ftp://prep.ai.mit.edu/pub/gnu/
2374 @node Advanced Usage, Very Advanced Usage, Simple Usage, Examples
2375 @section Advanced Usage
2379 You have a file that contains the URLs you want to download? Use the
2386 If you specify @samp{-} as file name, the @sc{url}s will be read from
2390 Create a five levels deep mirror image of the GNU web site, with the
2391 same directory structure the original has, with only one try per
2392 document, saving the log of the activities to @file{gnulog}:
2395 wget -r http://www.gnu.org/ -o gnulog
2399 The same as the above, but convert the links in the @sc{html} files to
2400 point to local files, so you can view the documents off-line:
2403 wget --convert-links -r http://www.gnu.org/ -o gnulog
2407 Retrieve only one HTML page, but make sure that all the elements needed
2408 for the page to be displayed, such as inline images and external style
2409 sheets, are also downloaded. Also make sure the downloaded page
2410 references the downloaded links.
2413 wget -p --convert-links http://www.server.com/dir/page.html
2416 The HTML page will be saved to @file{www.server.com/dir/page.html}, and
2417 the images, stylesheets, etc., somewhere under @file{www.server.com/},
2418 depending on where they were on the remote server.
2421 The same as the above, but without the @file{www.server.com/} directory.
2422 In fact, I don't want to have all those random server directories
2423 anyway---just save @emph{all} those files under a @file{download/}
2424 subdirectory of the current directory.
2427 wget -p --convert-links -nH -nd -Pdownload \
2428 http://www.server.com/dir/page.html
2432 Retrieve the index.html of @samp{www.lycos.com}, showing the original
2436 wget -S http://www.lycos.com/
2440 Save the server headers with the file, perhaps for post-processing.
2443 wget -s http://www.lycos.com/
2448 Retrieve the first two levels of @samp{wuarchive.wustl.edu}, saving them
2452 wget -r -l2 -P/tmp ftp://wuarchive.wustl.edu/
2456 You want to download all the @sc{gif}s from a directory on an @sc{http}
2457 server. You tried @samp{wget http://www.server.com/dir/*.gif}, but that
2458 didn't work because @sc{http} retrieval does not support globbing. In
2462 wget -r -l1 --no-parent -A.gif http://www.server.com/dir/
2465 More verbose, but the effect is the same. @samp{-r -l1} means to
2466 retrieve recursively (@pxref{Recursive Retrieval}), with maximum depth
2467 of 1. @samp{--no-parent} means that references to the parent directory
2468 are ignored (@pxref{Directory-Based Limits}), and @samp{-A.gif} means to
2469 download only the @sc{gif} files. @samp{-A "*.gif"} would have worked
2473 Suppose you were in the middle of downloading, when Wget was
2474 interrupted. Now you do not want to clobber the files already present.
2478 wget -nc -r http://www.gnu.org/
2482 If you want to encode your own username and password to @sc{http} or
2483 @sc{ftp}, use the appropriate @sc{url} syntax (@pxref{URL Format}).
2486 wget ftp://hniksic:mypassword@@unix.server.com/.emacs
2489 Note, however, that this usage is not advisable on multi-user systems
2490 because it reveals your password to anyone who looks at the output of
2493 @cindex redirecting output
2495 You would like the output documents to go to standard output instead of
2499 wget -O - http://jagor.srce.hr/ http://www.srce.hr/
2502 You can also combine the two options and make pipelines to retrieve the
2503 documents from remote hotlists:
2506 wget -O - http://cool.list.com/ | wget --force-html -i -
2510 @node Very Advanced Usage, , Advanced Usage, Examples
2511 @section Very Advanced Usage
2516 If you wish Wget to keep a mirror of a page (or @sc{ftp}
2517 subdirectories), use @samp{--mirror} (@samp{-m}), which is the shorthand
2518 for @samp{-r -l inf -N}. You can put Wget in the crontab file asking it
2519 to recheck a site each Sunday:
2523 0 0 * * 0 wget --mirror http://www.gnu.org/ -o /home/me/weeklog
2527 In addition to the above, you want the links to be converted for local
2528 viewing. But, after having read this manual, you know that link
2529 conversion doesn't play well with timestamping, so you also want Wget to
2530 back up the original HTML files before the conversion. Wget invocation
2531 would look like this:
2534 wget --mirror --convert-links --backup-converted \
2535 http://www.gnu.org/ -o /home/me/weeklog
2539 But you've also noticed that local viewing doesn't work all that well
2540 when HTML files are saved under extensions other than @samp{.html},
2541 perhaps because they were served as @file{index.cgi}. So you'd like
2542 Wget to rename all the files served with content-type @samp{text/html}
2543 to @file{@var{name}.html}.
2546 wget --mirror --convert-links --backup-converted \
2547 --html-extension -o /home/me/weeklog \
2551 Or, with less typing:
2554 wget -m -k -K -E http://www.gnu.org/ -o /home/me/weeklog
2559 @node Various, Appendices, Examples, Top
2563 This chapter contains all the stuff that could not fit anywhere else.
2566 * Proxies:: Support for proxy servers
2567 * Distribution:: Getting the latest version.
2568 * Mailing List:: Wget mailing list for announcements and discussion.
2569 * Reporting Bugs:: How and where to report bugs.
2570 * Portability:: The systems Wget works on.
2571 * Signals:: Signal-handling performed by Wget.
2574 @node Proxies, Distribution, Various, Various
2578 @dfn{Proxies} are special-purpose @sc{http} servers designed to transfer
2579 data from remote servers to local clients. One typical use of proxies
2580 is lightening network load for users behind a slow connection. This is
2581 achieved by channeling all @sc{http} and @sc{ftp} requests through the
2582 proxy which caches the transferred data. When a cached resource is
2583 requested again, proxy will return the data from cache. Another use for
2584 proxies is for companies that separate (for security reasons) their
2585 internal networks from the rest of Internet. In order to obtain
2586 information from the Web, their users connect and retrieve remote data
2587 using an authorized proxy.
2589 Wget supports proxies for both @sc{http} and @sc{ftp} retrievals. The
2590 standard way to specify proxy location, which Wget recognizes, is using
2591 the following environment variables:
2595 This variable should contain the @sc{url} of the proxy for @sc{http}
2599 This variable should contain the @sc{url} of the proxy for @sc{ftp}
2600 connections. It is quite common that @sc{http_proxy} and @sc{ftp_proxy}
2601 are set to the same @sc{url}.
2604 This variable should contain a comma-separated list of domain extensions
2605 proxy should @emph{not} be used for. For instance, if the value of
2606 @code{no_proxy} is @samp{.mit.edu}, proxy will not be used to retrieve
2610 In addition to the environment variables, proxy location and settings
2611 may be specified from within Wget itself.
2615 @itemx --proxy=on/off
2616 @itemx proxy = on/off
2617 This option may be used to turn the proxy support on or off. Proxy
2618 support is on by default, provided that the appropriate environment
2621 @item http_proxy = @var{URL}
2622 @itemx ftp_proxy = @var{URL}
2623 @itemx no_proxy = @var{string}
2624 These startup file variables allow you to override the proxy settings
2625 specified by the environment.
2628 Some proxy servers require authorization to enable you to use them. The
2629 authorization consists of @dfn{username} and @dfn{password}, which must
2630 be sent by Wget. As with @sc{http} authorization, several
2631 authentication schemes exist. For proxy authorization only the
2632 @code{Basic} authentication scheme is currently implemented.
2634 You may specify your username and password either through the proxy
2635 @sc{url} or through the command-line options. Assuming that the
2636 company's proxy is located at @samp{proxy.company.com} at port 8001, a
2637 proxy @sc{url} location containing authorization data might look like
2641 http://hniksic:mypassword@@proxy.company.com:8001/
2644 Alternatively, you may use the @samp{proxy-user} and
2645 @samp{proxy-password} options, and the equivalent @file{.wgetrc}
2646 settings @code{proxy_user} and @code{proxy_passwd} to set the proxy
2647 username and password.
2649 @node Distribution, Mailing List, Proxies, Various
2650 @section Distribution
2651 @cindex latest version
2653 Like all GNU utilities, the latest version of Wget can be found at the
2654 master GNU archive site prep.ai.mit.edu, and its mirrors. For example,
2655 Wget @value{VERSION} can be found at
2656 @url{ftp://prep.ai.mit.edu/gnu/wget/wget-@value{VERSION}.tar.gz}
2658 @node Mailing List, Reporting Bugs, Distribution, Various
2659 @section Mailing List
2660 @cindex mailing list
2663 Wget has its own mailing list at @email{wget@@sunsite.dk}, thanks
2664 to Karsten Thygesen. The mailing list is for discussion of Wget
2665 features and web, reporting Wget bugs (those that you think may be of
2666 interest to the public) and mailing announcements. You are welcome to
2667 subscribe. The more people on the list, the better!
2669 To subscribe, send mail to @email{wget-subscribe@@sunsite.dk}.
2670 the magic word @samp{subscribe} in the subject line. Unsubscribe by
2671 mailing to @email{wget-unsubscribe@@sunsite.dk}.
2673 The mailing list is archived at @url{http://fly.srk.fer.hr/archive/wget}.
2674 Alternative archive is available at
2675 @url{http://www.mail-archive.com/wget%40sunsite.auc.dk/}.
2677 @node Reporting Bugs, Portability, Mailing List, Various
2678 @section Reporting Bugs
2680 @cindex reporting bugs
2684 You are welcome to send bug reports about GNU Wget to
2685 @email{bug-wget@@gnu.org}.
2687 Before actually submitting a bug report, please try to follow a few
2692 Please try to ascertain that the behaviour you see really is a bug. If
2693 Wget crashes, it's a bug. If Wget does not behave as documented,
2694 it's a bug. If things work strange, but you are not sure about the way
2695 they are supposed to work, it might well be a bug.
2698 Try to repeat the bug in as simple circumstances as possible. E.g. if
2699 Wget crashes while downloading @samp{wget -rl0 -kKE -t5 -Y0
2700 http://yoyodyne.com -o /tmp/log}, you should try to see if the crash is
2701 repeatable, and if will occur with a simpler set of options. You might
2702 even try to start the download at the page where the crash occurred to
2703 see if that page somehow triggered the crash.
2705 Also, while I will probably be interested to know the contents of your
2706 @file{.wgetrc} file, just dumping it into the debug message is probably
2707 a bad idea. Instead, you should first try to see if the bug repeats
2708 with @file{.wgetrc} moved out of the way. Only if it turns out that
2709 @file{.wgetrc} settings affect the bug, mail me the relevant parts of
2713 Please start Wget with @samp{-d} option and send the log (or the
2714 relevant parts of it). If Wget was compiled without debug support,
2715 recompile it. It is @emph{much} easier to trace bugs with debug support
2719 If Wget has crashed, try to run it in a debugger, e.g. @code{gdb `which
2720 wget` core} and type @code{where} to get the backtrace.
2724 @node Portability, Signals, Reporting Bugs, Various
2725 @section Portability
2727 @cindex operating systems
2729 Since Wget uses GNU Autoconf for building and configuring, and avoids
2730 using ``special'' ultra--mega--cool features of any particular Unix, it
2731 should compile (and work) on all common Unix flavors.
2733 Various Wget versions have been compiled and tested under many kinds of
2734 Unix systems, including Solaris, Linux, SunOS, OSF (aka Digital Unix),
2735 Ultrix, *BSD, IRIX, and others; refer to the file @file{MACHINES} in the
2736 distribution directory for a comprehensive list. If you compile it on
2737 an architecture not listed there, please let me know so I can update it.
2739 Wget should also compile on the other Unix systems, not listed in
2740 @file{MACHINES}. If it doesn't, please let me know.
2742 Thanks to kind contributors, this version of Wget compiles and works on
2743 Microsoft Windows 95 and Windows NT platforms. It has been compiled
2744 successfully using MS Visual C++ 4.0, Watcom, and Borland C compilers,
2745 with Winsock as networking software. Naturally, it is crippled of some
2746 features available on Unix, but it should work as a substitute for
2747 people stuck with Windows. Note that the Windows port is
2748 @strong{neither tested nor maintained} by me---all questions and
2749 problems should be reported to Wget mailing list at
2750 @email{wget@@sunsite.dk} where the maintainers will look at them.
2752 @node Signals, , Portability, Various
2754 @cindex signal handling
2757 Since the purpose of Wget is background work, it catches the hangup
2758 signal (@code{SIGHUP}) and ignores it. If the output was on standard
2759 output, it will be redirected to a file named @file{wget-log}.
2760 Otherwise, @code{SIGHUP} is ignored. This is convenient when you wish
2761 to redirect the output of Wget after having started it.
2764 $ wget http://www.ifi.uio.no/~larsi/gnus.tar.gz &
2765 $ kill -HUP %% # Redirect the output to wget-log
2768 Other than that, Wget will not try to interfere with signals in any way.
2769 @kbd{C-c}, @code{kill -TERM} and @code{kill -KILL} should kill it alike.
2771 @node Appendices, Copying, Various, Top
2774 This chapter contains some references I consider useful.
2777 * Robot Exclusion:: Wget's support for RES.
2778 * Security Considerations:: Security with Wget.
2779 * Contributors:: People who helped.
2782 @node Robot Exclusion, Security Considerations, Appendices, Appendices
2783 @section Robot Exclusion
2784 @cindex robot exclusion
2786 @cindex server maintenance
2788 It is extremely easy to make Wget wander aimlessly around a web site,
2789 sucking all the available data in progress. @samp{wget -r @var{site}},
2790 and you're set. Great? Not for the server admin.
2792 As long as Wget is only retrieving static pages, and doing it at a
2793 reasonable rate (see the @samp{--wait} option), there's not much of a
2794 problem. The trouble is that Wget can't tell the difference between the
2795 smallest static page and the most demanding CGI. A site I know has a
2796 section handled by an, uh, @dfn{bitchin'} CGI Perl script that converts
2797 Info files to HTML on the fly. The script is slow, but works well
2798 enough for human users viewing an occasional Info file. However, when
2799 someone's recursive Wget download stumbles upon the index page that
2800 links to all the Info files through the script, the system is brought to
2801 its knees without providing anything useful to the downloader.
2803 To avoid this kind of accident, as well as to preserve privacy for
2804 documents that need to be protected from well-behaved robots, the
2805 concept of @dfn{robot exclusion} has been invented. The idea is that
2806 the server administrators and document authors can specify which
2807 portions of the site they wish to protect from the robots.
2809 The most popular mechanism, and the de facto standard supported by all
2810 the major robots, is the ``Robots Exclusion Standard'' (RES) written by
2811 Martijn Koster et al. in 1994. It specifies the format of a text file
2812 containing directives that instruct the robots which URL paths to avoid.
2813 To be found by the robots, the specifications must be placed in
2814 @file{/robots.txt} in the server root, which the robots are supposed to
2817 Although Wget is not a web robot in the strictest sense of the word, it
2818 can downloads large parts of the site without the user's intervention to
2819 download an individual page. Because of that, Wget honors RES when
2820 downloading recursively. For instance, when you issue:
2823 wget -r http://www.server.com/
2826 First the index of @samp{www.server.com} will be downloaded. If Wget
2827 finds that it wants to download more documents from that server, it will
2828 request @samp{http://www.server.com/robots.txt} and, if found, use it
2829 for further downloads. @file{robots.txt} is loaded only once per each
2832 Until version 1.8, Wget supported the first version of the standard,
2833 written by Martijn Koster in 1994 and available at
2834 @url{http://www.robotstxt.org/wc/norobots.html}. As of version 1.8,
2835 Wget has supported the additional directives specified in the internet
2836 draft @samp{<draft-koster-robots-00.txt>} titled ``A Method for Web
2837 Robots Control''. The draft, which has as far as I know never made to
2838 an @sc{rfc}, is available at
2839 @url{http://www.robotstxt.org/wc/norobots-rfc.txt}.
2841 This manual no longer includes the text of the Robot Exclusion Standard.
2843 The second, less known mechanism, enables the author of an individual
2844 document to specify whether they want the links from the file to be
2845 followed by a robot. This is achieved using the @code{META} tag, like
2849 <meta name="robots" content="nofollow">
2852 This is explained in some detail at
2853 @url{http://www.robotstxt.org/wc/meta-user.html}. Wget supports this
2854 method of robot exclusion in addition to the usual @file{/robots.txt}
2857 If you know what you are doing and really really wish to turn off the
2858 robot exclusion, set the @code{robots} variable to @samp{off} in your
2859 @file{.wgetrc}. You can achieve the same effect from the command line
2860 using the @code{-e} switch, e.g. @samp{wget -e robots=off @var{url}...}.
2862 @node Security Considerations, Contributors, Robot Exclusion, Appendices
2863 @section Security Considerations
2866 When using Wget, you must be aware that it sends unencrypted passwords
2867 through the network, which may present a security problem. Here are the
2868 main issues, and some solutions.
2871 @item The passwords on the command line are visible using @code{ps}.
2872 The best way around it is to use @code{wget -i -} and feed the @sc{url}s
2873 to Wget's standard input, each on a separate line, terminated by
2874 @kbd{C-d}. Another workaround is to use @file{.netrc} to store
2875 passwords; however, storing unencrypted passwords is also considered a
2879 Using the insecure @dfn{basic} authentication scheme, unencrypted
2880 passwords are transmitted through the network routers and gateways.
2883 The @sc{ftp} passwords are also in no way encrypted. There is no good
2884 solution for this at the moment.
2887 Although the ``normal'' output of Wget tries to hide the passwords,
2888 debugging logs show them, in all forms. This problem is avoided by
2889 being careful when you send debug logs (yes, even when you send them to
2893 @node Contributors, , Security Considerations, Appendices
2894 @section Contributors
2895 @cindex contributors
2898 GNU Wget was written by Hrvoje Nik@v{s}i@'{c} @email{hniksic@@arsdigita.com}.
2901 GNU Wget was written by Hrvoje Niksic @email{hniksic@@arsdigita.com}.
2903 However, its development could never have gone as far as it has, were it
2904 not for the help of many people, either with bug reports, feature
2905 proposals, patches, or letters saying ``Thanks!''.
2907 Special thanks goes to the following people (no particular order):
2911 Karsten Thygesen---donated system resources such as the mailing list,
2912 web space, and @sc{ftp} space, along with a lot of time to make these
2916 Shawn McHorse---bug reports and patches.
2919 Kaveh R. Ghazi---on-the-fly @code{ansi2knr}-ization. Lots of
2923 Gordon Matzigkeit---@file{.netrc} support.
2927 Zlatko @v{C}alu@v{s}i@'{c}, Tomislav Vujec and Dra@v{z}en
2928 Ka@v{c}ar---feature suggestions and ``philosophical'' discussions.
2931 Zlatko Calusic, Tomislav Vujec and Drazen Kacar---feature suggestions
2932 and ``philosophical'' discussions.
2936 Darko Budor---initial port to Windows.
2939 Antonio Rosella---help and suggestions, plus the Italian translation.
2943 Tomislav Petrovi@'{c}, Mario Miko@v{c}evi@'{c}---many bug reports and
2947 Tomislav Petrovic, Mario Mikocevic---many bug reports and suggestions.
2952 Fran@,{c}ois Pinard---many thorough bug reports and discussions.
2955 Francois Pinard---many thorough bug reports and discussions.
2959 Karl Eichwalder---lots of help with internationalization and other
2963 Junio Hamano---donated support for Opie and @sc{http} @code{Digest}
2967 The people who provided donations for development, including Brian
2971 The following people have provided patches, bug/build reports, useful
2972 suggestions, beta testing services, fan mail and all the other things
2973 that make maintenance so much fun:
2992 Kristijan @v{C}onka@v{s},
3010 Aleksandar Erkalovi@'{c},
3013 Aleksandar Erkalovic,
3029 Erik Magnus Hulthen,
3047 Goran Kezunovi@'{c},
3058 $\Sigma\acute{\iota}\mu o\varsigma\;
3059 \Xi\varepsilon\nu\iota\tau\acute{\epsilon}\lambda\lambda\eta\varsigma$
3060 (Simos KSenitellis),
3068 Nicol@'{a}s Lichtmeier,
3074 Alexander V. Lukyanov,
3099 @c Texinfo doesn't grok @'{@i}, so we have to use TeX itself.
3101 Juan Jos\'{e} Rodr\'{\i}gues,
3104 Juan Jose Rodrigues,
3116 Szakacsits Szabolcs,
3122 Douglas E. Wegscheid,
3132 Apologies to all who I accidentally left out, and many thanks to all the
3133 subscribers of the Wget mailing list.
3135 @node Copying, Concept Index, Appendices, Top
3140 @cindex free software
3142 GNU Wget is licensed under the GNU GPL, which makes it @dfn{free
3145 Please note that ``free'' in ``free software'' refers to liberty, not
3146 price. As some GNU project advocates like to point out, think of ``free
3147 speech'' rather than ``free beer''. The exact and legally binding
3148 distribution terms are spelled out below; in short, you have the right
3149 (freedom) to run and change Wget and distribute it to other people, and
3150 even---if you want---charge money for doing either. The important
3151 restriction is that you have to grant your recipients the same rights
3152 and impose the same restrictions.
3154 This method of licensing software is also known as @dfn{open source}
3155 because, among other things, it makes sure that all recipients will
3156 receive the source code along with the program, and be able to improve
3157 it. The GNU project prefers the term ``free software'' for reasons
3159 @url{http://www.gnu.org/philosophy/free-software-for-freedom.html}.
3161 The exact license terms are defined by this paragraph and the GNU
3162 General Public License it refers to:
3165 GNU Wget is free software; you can redistribute it and/or modify it
3166 under the terms of the GNU General Public License as published by the
3167 Free Software Foundation; either version 2 of the License, or (at your
3168 option) any later version.
3170 GNU Wget is distributed in the hope that it will be useful, but WITHOUT
3171 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
3172 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
3175 A copy of the GNU General Public License is included as part of this
3176 manual; if you did not receive it, write to the Free Software
3177 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
3180 In addition to this, this manual is free in the same sense:
3183 Permission is granted to copy, distribute and/or modify this document
3184 under the terms of the GNU Free Documentation License, Version 1.1 or
3185 any later version published by the Free Software Foundation; with the
3186 Invariant Sections being ``GNU General Public License'' and ``GNU Free
3187 Documentation License'', with no Front-Cover Texts, and with no
3188 Back-Cover Texts. A copy of the license is included in the section
3189 entitled ``GNU Free Documentation License''.
3192 @c #### Maybe we should wrap these licenses in ifinfo? Stallman says
3193 @c that the GFDL needs to be present in the manual, and to me it would
3194 @c suck to include the license for the manual and not the license for
3197 The full texts of the GNU General Public License and of the GNU Free
3198 Documentation License are available below.
3201 * GNU General Public License::
3202 * GNU Free Documentation License::
3205 @node GNU General Public License, GNU Free Documentation License, Copying, Copying
3206 @section GNU General Public License
3207 @center Version 2, June 1991
3210 Copyright @copyright{} 1989, 1991 Free Software Foundation, Inc.
3211 675 Mass Ave, Cambridge, MA 02139, USA
3213 Everyone is permitted to copy and distribute verbatim copies
3214 of this license document, but changing it is not allowed.
3217 @unnumberedsec Preamble
3219 The licenses for most software are designed to take away your
3220 freedom to share and change it. By contrast, the GNU General Public
3221 License is intended to guarantee your freedom to share and change free
3222 software---to make sure the software is free for all its users. This
3223 General Public License applies to most of the Free Software
3224 Foundation's software and to any other program whose authors commit to
3225 using it. (Some other Free Software Foundation software is covered by
3226 the GNU Library General Public License instead.) You can apply it to
3229 When we speak of free software, we are referring to freedom, not
3230 price. Our General Public Licenses are designed to make sure that you
3231 have the freedom to distribute copies of free software (and charge for
3232 this service if you wish), that you receive source code or can get it
3233 if you want it, that you can change the software or use pieces of it
3234 in new free programs; and that you know you can do these things.
3236 To protect your rights, we need to make restrictions that forbid
3237 anyone to deny you these rights or to ask you to surrender the rights.
3238 These restrictions translate to certain responsibilities for you if you
3239 distribute copies of the software, or if you modify it.
3241 For example, if you distribute copies of such a program, whether
3242 gratis or for a fee, you must give the recipients all the rights that
3243 you have. You must make sure that they, too, receive or can get the
3244 source code. And you must show them these terms so they know their
3247 We protect your rights with two steps: (1) copyright the software, and
3248 (2) offer you this license which gives you legal permission to copy,
3249 distribute and/or modify the software.
3251 Also, for each author's protection and ours, we want to make certain
3252 that everyone understands that there is no warranty for this free
3253 software. If the software is modified by someone else and passed on, we
3254 want its recipients to know that what they have is not the original, so
3255 that any problems introduced by others will not reflect on the original
3256 authors' reputations.
3258 Finally, any free program is threatened constantly by software
3259 patents. We wish to avoid the danger that redistributors of a free
3260 program will individually obtain patent licenses, in effect making the
3261 program proprietary. To prevent this, we have made it clear that any
3262 patent must be licensed for everyone's free use or not licensed at all.
3264 The precise terms and conditions for copying, distribution and
3265 modification follow.
3268 @unnumberedsec TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
3271 @center TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
3276 This License applies to any program or other work which contains
3277 a notice placed by the copyright holder saying it may be distributed
3278 under the terms of this General Public License. The ``Program'', below,
3279 refers to any such program or work, and a ``work based on the Program''
3280 means either the Program or any derivative work under copyright law:
3281 that is to say, a work containing the Program or a portion of it,
3282 either verbatim or with modifications and/or translated into another
3283 language. (Hereinafter, translation is included without limitation in
3284 the term ``modification''.) Each licensee is addressed as ``you''.
3286 Activities other than copying, distribution and modification are not
3287 covered by this License; they are outside its scope. The act of
3288 running the Program is not restricted, and the output from the Program
3289 is covered only if its contents constitute a work based on the
3290 Program (independent of having been made by running the Program).
3291 Whether that is true depends on what the Program does.
3294 You may copy and distribute verbatim copies of the Program's
3295 source code as you receive it, in any medium, provided that you
3296 conspicuously and appropriately publish on each copy an appropriate
3297 copyright notice and disclaimer of warranty; keep intact all the
3298 notices that refer to this License and to the absence of any warranty;
3299 and give any other recipients of the Program a copy of this License
3300 along with the Program.
3302 You may charge a fee for the physical act of transferring a copy, and
3303 you may at your option offer warranty protection in exchange for a fee.
3306 You may modify your copy or copies of the Program or any portion
3307 of it, thus forming a work based on the Program, and copy and
3308 distribute such modifications or work under the terms of Section 1
3309 above, provided that you also meet all of these conditions:
3313 You must cause the modified files to carry prominent notices
3314 stating that you changed the files and the date of any change.
3317 You must cause any work that you distribute or publish, that in
3318 whole or in part contains or is derived from the Program or any
3319 part thereof, to be licensed as a whole at no charge to all third
3320 parties under the terms of this License.
3323 If the modified program normally reads commands interactively
3324 when run, you must cause it, when started running for such
3325 interactive use in the most ordinary way, to print or display an
3326 announcement including an appropriate copyright notice and a
3327 notice that there is no warranty (or else, saying that you provide
3328 a warranty) and that users may redistribute the program under
3329 these conditions, and telling the user how to view a copy of this
3330 License. (Exception: if the Program itself is interactive but
3331 does not normally print such an announcement, your work based on
3332 the Program is not required to print an announcement.)
3335 These requirements apply to the modified work as a whole. If
3336 identifiable sections of that work are not derived from the Program,
3337 and can be reasonably considered independent and separate works in
3338 themselves, then this License, and its terms, do not apply to those
3339 sections when you distribute them as separate works. But when you
3340 distribute the same sections as part of a whole which is a work based
3341 on the Program, the distribution of the whole must be on the terms of
3342 this License, whose permissions for other licensees extend to the
3343 entire whole, and thus to each and every part regardless of who wrote it.
3345 Thus, it is not the intent of this section to claim rights or contest
3346 your rights to work written entirely by you; rather, the intent is to
3347 exercise the right to control the distribution of derivative or
3348 collective works based on the Program.
3350 In addition, mere aggregation of another work not based on the Program
3351 with the Program (or with a work based on the Program) on a volume of
3352 a storage or distribution medium does not bring the other work under
3353 the scope of this License.
3356 You may copy and distribute the Program (or a work based on it,
3357 under Section 2) in object code or executable form under the terms of
3358 Sections 1 and 2 above provided that you also do one of the following:
3362 Accompany it with the complete corresponding machine-readable
3363 source code, which must be distributed under the terms of Sections
3364 1 and 2 above on a medium customarily used for software interchange; or,
3367 Accompany it with a written offer, valid for at least three
3368 years, to give any third party, for a charge no more than your
3369 cost of physically performing source distribution, a complete
3370 machine-readable copy of the corresponding source code, to be
3371 distributed under the terms of Sections 1 and 2 above on a medium
3372 customarily used for software interchange; or,
3375 Accompany it with the information you received as to the offer
3376 to distribute corresponding source code. (This alternative is
3377 allowed only for noncommercial distribution and only if you
3378 received the program in object code or executable form with such
3379 an offer, in accord with Subsection b above.)
3382 The source code for a work means the preferred form of the work for
3383 making modifications to it. For an executable work, complete source
3384 code means all the source code for all modules it contains, plus any
3385 associated interface definition files, plus the scripts used to
3386 control compilation and installation of the executable. However, as a
3387 special exception, the source code distributed need not include
3388 anything that is normally distributed (in either source or binary
3389 form) with the major components (compiler, kernel, and so on) of the
3390 operating system on which the executable runs, unless that component
3391 itself accompanies the executable.
3393 If distribution of executable or object code is made by offering
3394 access to copy from a designated place, then offering equivalent
3395 access to copy the source code from the same place counts as
3396 distribution of the source code, even though third parties are not
3397 compelled to copy the source along with the object code.
3400 You may not copy, modify, sublicense, or distribute the Program
3401 except as expressly provided under this License. Any attempt
3402 otherwise to copy, modify, sublicense or distribute the Program is
3403 void, and will automatically terminate your rights under this License.
3404 However, parties who have received copies, or rights, from you under
3405 this License will not have their licenses terminated so long as such
3406 parties remain in full compliance.
3409 You are not required to accept this License, since you have not
3410 signed it. However, nothing else grants you permission to modify or
3411 distribute the Program or its derivative works. These actions are
3412 prohibited by law if you do not accept this License. Therefore, by
3413 modifying or distributing the Program (or any work based on the
3414 Program), you indicate your acceptance of this License to do so, and
3415 all its terms and conditions for copying, distributing or modifying
3416 the Program or works based on it.
3419 Each time you redistribute the Program (or any work based on the
3420 Program), the recipient automatically receives a license from the
3421 original licensor to copy, distribute or modify the Program subject to
3422 these terms and conditions. You may not impose any further
3423 restrictions on the recipients' exercise of the rights granted herein.
3424 You are not responsible for enforcing compliance by third parties to
3428 If, as a consequence of a court judgment or allegation of patent
3429 infringement or for any other reason (not limited to patent issues),
3430 conditions are imposed on you (whether by court order, agreement or
3431 otherwise) that contradict the conditions of this License, they do not
3432 excuse you from the conditions of this License. If you cannot
3433 distribute so as to satisfy simultaneously your obligations under this
3434 License and any other pertinent obligations, then as a consequence you
3435 may not distribute the Program at all. For example, if a patent
3436 license would not permit royalty-free redistribution of the Program by
3437 all those who receive copies directly or indirectly through you, then
3438 the only way you could satisfy both it and this License would be to
3439 refrain entirely from distribution of the Program.
3441 If any portion of this section is held invalid or unenforceable under
3442 any particular circumstance, the balance of the section is intended to
3443 apply and the section as a whole is intended to apply in other
3446 It is not the purpose of this section to induce you to infringe any
3447 patents or other property right claims or to contest validity of any
3448 such claims; this section has the sole purpose of protecting the
3449 integrity of the free software distribution system, which is
3450 implemented by public license practices. Many people have made
3451 generous contributions to the wide range of software distributed
3452 through that system in reliance on consistent application of that
3453 system; it is up to the author/donor to decide if he or she is willing
3454 to distribute software through any other system and a licensee cannot
3457 This section is intended to make thoroughly clear what is believed to
3458 be a consequence of the rest of this License.
3461 If the distribution and/or use of the Program is restricted in
3462 certain countries either by patents or by copyrighted interfaces, the
3463 original copyright holder who places the Program under this License
3464 may add an explicit geographical distribution limitation excluding
3465 those countries, so that distribution is permitted only in or among
3466 countries not thus excluded. In such case, this License incorporates
3467 the limitation as if written in the body of this License.
3470 The Free Software Foundation may publish revised and/or new versions
3471 of the General Public License from time to time. Such new versions will
3472 be similar in spirit to the present version, but may differ in detail to
3473 address new problems or concerns.
3475 Each version is given a distinguishing version number. If the Program
3476 specifies a version number of this License which applies to it and ``any
3477 later version'', you have the option of following the terms and conditions
3478 either of that version or of any later version published by the Free
3479 Software Foundation. If the Program does not specify a version number of
3480 this License, you may choose any version ever published by the Free Software
3484 If you wish to incorporate parts of the Program into other free
3485 programs whose distribution conditions are different, write to the author
3486 to ask for permission. For software which is copyrighted by the Free
3487 Software Foundation, write to the Free Software Foundation; we sometimes
3488 make exceptions for this. Our decision will be guided by the two goals
3489 of preserving the free status of all derivatives of our free software and
3490 of promoting the sharing and reuse of software generally.
3493 @heading NO WARRANTY
3501 BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
3502 FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
3503 OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
3504 PROVIDE THE PROGRAM ``AS IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
3505 OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
3506 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
3507 TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
3508 PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
3509 REPAIR OR CORRECTION.
3512 IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
3513 WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
3514 REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
3515 INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
3516 OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
3517 TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
3518 YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
3519 PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
3520 POSSIBILITY OF SUCH DAMAGES.
3524 @heading END OF TERMS AND CONDITIONS
3527 @center END OF TERMS AND CONDITIONS
3531 @unnumberedsec How to Apply These Terms to Your New Programs
3533 If you develop a new program, and you want it to be of the greatest
3534 possible use to the public, the best way to achieve this is to make it
3535 free software which everyone can redistribute and change under these terms.
3537 To do so, attach the following notices to the program. It is safest
3538 to attach them to the start of each source file to most effectively
3539 convey the exclusion of warranty; and each file should have at least
3540 the ``copyright'' line and a pointer to where the full notice is found.
3543 @var{one line to give the program's name and an idea of what it does.}
3544 Copyright (C) 19@var{yy} @var{name of author}
3546 This program is free software; you can redistribute it and/or
3547 modify it under the terms of the GNU General Public License
3548 as published by the Free Software Foundation; either version 2
3549 of the License, or (at your option) any later version.
3551 This program is distributed in the hope that it will be useful,
3552 but WITHOUT ANY WARRANTY; without even the implied warranty of
3553 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
3554 GNU General Public License for more details.
3556 You should have received a copy of the GNU General Public License
3557 along with this program; if not, write to the Free Software
3558 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
3561 Also add information on how to contact you by electronic and paper mail.
3563 If the program is interactive, make it output a short notice like this
3564 when it starts in an interactive mode:
3567 Gnomovision version 69, Copyright (C) 19@var{yy} @var{name of author}
3568 Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
3569 type `show w'. This is free software, and you are welcome
3570 to redistribute it under certain conditions; type `show c'
3574 The hypothetical commands @samp{show w} and @samp{show c} should show
3575 the appropriate parts of the General Public License. Of course, the
3576 commands you use may be called something other than @samp{show w} and
3577 @samp{show c}; they could even be mouse-clicks or menu items---whatever
3580 You should also get your employer (if you work as a programmer) or your
3581 school, if any, to sign a ``copyright disclaimer'' for the program, if
3582 necessary. Here is a sample; alter the names:
3586 Yoyodyne, Inc., hereby disclaims all copyright
3587 interest in the program `Gnomovision'
3588 (which makes passes at compilers) written
3591 @var{signature of Ty Coon}, 1 April 1989
3592 Ty Coon, President of Vice
3596 This General Public License does not permit incorporating your program into
3597 proprietary programs. If your program is a subroutine library, you may
3598 consider it more useful to permit linking proprietary applications with the
3599 library. If this is what you want to do, use the GNU Library General
3600 Public License instead of this License.
3602 @node GNU Free Documentation License, , GNU General Public License, Copying
3603 @section GNU Free Documentation License
3604 @center Version 1.1, March 2000
3607 Copyright (C) 2000 Free Software Foundation, Inc.
3608 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
3610 Everyone is permitted to copy and distribute verbatim copies
3611 of this license document, but changing it is not allowed.
3618 The purpose of this License is to make a manual, textbook, or other
3619 written document ``free'' in the sense of freedom: to assure everyone
3620 the effective freedom to copy and redistribute it, with or without
3621 modifying it, either commercially or noncommercially. Secondarily,
3622 this License preserves for the author and publisher a way to get
3623 credit for their work, while not being considered responsible for
3624 modifications made by others.
3626 This License is a kind of ``copyleft'', which means that derivative
3627 works of the document must themselves be free in the same sense. It
3628 complements the GNU General Public License, which is a copyleft
3629 license designed for free software.
3631 We have designed this License in order to use it for manuals for free
3632 software, because free software needs free documentation: a free
3633 program should come with manuals providing the same freedoms that the
3634 software does. But this License is not limited to software manuals;
3635 it can be used for any textual work, regardless of subject matter or
3636 whether it is published as a printed book. We recommend this License
3637 principally for works whose purpose is instruction or reference.
3641 APPLICABILITY AND DEFINITIONS
3643 This License applies to any manual or other work that contains a
3644 notice placed by the copyright holder saying it can be distributed
3645 under the terms of this License. The ``Document'', below, refers to any
3646 such manual or work. Any member of the public is a licensee, and is
3647 addressed as ``you''.
3649 A ``Modified Version'' of the Document means any work containing the
3650 Document or a portion of it, either copied verbatim, or with
3651 modifications and/or translated into another language.
3653 A ``Secondary Section'' is a named appendix or a front-matter section of
3654 the Document that deals exclusively with the relationship of the
3655 publishers or authors of the Document to the Document's overall subject
3656 (or to related matters) and contains nothing that could fall directly
3657 within that overall subject. (For example, if the Document is in part a
3658 textbook of mathematics, a Secondary Section may not explain any
3659 mathematics.) The relationship could be a matter of historical
3660 connection with the subject or with related matters, or of legal,
3661 commercial, philosophical, ethical or political position regarding
3664 The ``Invariant Sections'' are certain Secondary Sections whose titles
3665 are designated, as being those of Invariant Sections, in the notice
3666 that says that the Document is released under this License.
3668 The ``Cover Texts'' are certain short passages of text that are listed,
3669 as Front-Cover Texts or Back-Cover Texts, in the notice that says that
3670 the Document is released under this License.
3672 A ``Transparent'' copy of the Document means a machine-readable copy,
3673 represented in a format whose specification is available to the
3674 general public, whose contents can be viewed and edited directly and
3675 straightforwardly with generic text editors or (for images composed of
3676 pixels) generic paint programs or (for drawings) some widely available
3677 drawing editor, and that is suitable for input to text formatters or
3678 for automatic translation to a variety of formats suitable for input
3679 to text formatters. A copy made in an otherwise Transparent file
3680 format whose markup has been designed to thwart or discourage
3681 subsequent modification by readers is not Transparent. A copy that is
3682 not ``Transparent'' is called ``Opaque''.
3684 Examples of suitable formats for Transparent copies include plain
3685 ASCII without markup, Texinfo input format, LaTeX input format, SGML
3686 or XML using a publicly available DTD, and standard-conforming simple
3687 HTML designed for human modification. Opaque formats include
3688 PostScript, PDF, proprietary formats that can be read and edited only
3689 by proprietary word processors, SGML or XML for which the DTD and/or
3690 processing tools are not generally available, and the
3691 machine-generated HTML produced by some word processors for output
3694 The ``Title Page'' means, for a printed book, the title page itself,
3695 plus such following pages as are needed to hold, legibly, the material
3696 this License requires to appear in the title page. For works in
3697 formats which do not have any title page as such, ``Title Page'' means
3698 the text near the most prominent appearance of the work's title,
3699 preceding the beginning of the body of the text.
3704 You may copy and distribute the Document in any medium, either
3705 commercially or noncommercially, provided that this License, the
3706 copyright notices, and the license notice saying this License applies
3707 to the Document are reproduced in all copies, and that you add no other
3708 conditions whatsoever to those of this License. You may not use
3709 technical measures to obstruct or control the reading or further
3710 copying of the copies you make or distribute. However, you may accept
3711 compensation in exchange for copies. If you distribute a large enough
3712 number of copies you must also follow the conditions in section 3.
3714 You may also lend copies, under the same conditions stated above, and
3715 you may publicly display copies.
3720 If you publish printed copies of the Document numbering more than 100,
3721 and the Document's license notice requires Cover Texts, you must enclose
3722 the copies in covers that carry, clearly and legibly, all these Cover
3723 Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on
3724 the back cover. Both covers must also clearly and legibly identify
3725 you as the publisher of these copies. The front cover must present
3726 the full title with all words of the title equally prominent and
3727 visible. You may add other material on the covers in addition.
3728 Copying with changes limited to the covers, as long as they preserve
3729 the title of the Document and satisfy these conditions, can be treated
3730 as verbatim copying in other respects.
3732 If the required texts for either cover are too voluminous to fit
3733 legibly, you should put the first ones listed (as many as fit
3734 reasonably) on the actual cover, and continue the rest onto adjacent
3737 If you publish or distribute Opaque copies of the Document numbering
3738 more than 100, you must either include a machine-readable Transparent
3739 copy along with each Opaque copy, or state in or with each Opaque copy
3740 a publicly-accessible computer-network location containing a complete
3741 Transparent copy of the Document, free of added material, which the
3742 general network-using public has access to download anonymously at no
3743 charge using public-standard network protocols. If you use the latter
3744 option, you must take reasonably prudent steps, when you begin
3745 distribution of Opaque copies in quantity, to ensure that this
3746 Transparent copy will remain thus accessible at the stated location
3747 until at least one year after the last time you distribute an Opaque
3748 copy (directly or through your agents or retailers) of that edition to
3751 It is requested, but not required, that you contact the authors of the
3752 Document well before redistributing any large number of copies, to give
3753 them a chance to provide you with an updated version of the Document.
3758 You may copy and distribute a Modified Version of the Document under
3759 the conditions of sections 2 and 3 above, provided that you release
3760 the Modified Version under precisely this License, with the Modified
3761 Version filling the role of the Document, thus licensing distribution
3762 and modification of the Modified Version to whoever possesses a copy
3763 of it. In addition, you must do these things in the Modified Version:
3765 A. Use in the Title Page (and on the covers, if any) a title distinct
3766 from that of the Document, and from those of previous versions
3767 (which should, if there were any, be listed in the History section
3768 of the Document). You may use the same title as a previous version
3769 if the original publisher of that version gives permission.@*
3770 B. List on the Title Page, as authors, one or more persons or entities
3771 responsible for authorship of the modifications in the Modified
3772 Version, together with at least five of the principal authors of the
3773 Document (all of its principal authors, if it has less than five).@*
3774 C. State on the Title page the name of the publisher of the
3775 Modified Version, as the publisher.@*
3776 D. Preserve all the copyright notices of the Document.@*
3777 E. Add an appropriate copyright notice for your modifications
3778 adjacent to the other copyright notices.@*
3779 F. Include, immediately after the copyright notices, a license notice
3780 giving the public permission to use the Modified Version under the
3781 terms of this License, in the form shown in the Addendum below.@*
3782 G. Preserve in that license notice the full lists of Invariant Sections
3783 and required Cover Texts given in the Document's license notice.@*
3784 H. Include an unaltered copy of this License.@*
3785 I. Preserve the section entitled ``History'', and its title, and add to
3786 it an item stating at least the title, year, new authors, and
3787 publisher of the Modified Version as given on the Title Page. If
3788 there is no section entitled ``History'' in the Document, create one
3789 stating the title, year, authors, and publisher of the Document as
3790 given on its Title Page, then add an item describing the Modified
3791 Version as stated in the previous sentence.@*
3792 J. Preserve the network location, if any, given in the Document for
3793 public access to a Transparent copy of the Document, and likewise
3794 the network locations given in the Document for previous versions
3795 it was based on. These may be placed in the ``History'' section.
3796 You may omit a network location for a work that was published at
3797 least four years before the Document itself, or if the original
3798 publisher of the version it refers to gives permission.@*
3799 K. In any section entitled ``Acknowledgements'' or ``Dedications'',
3800 preserve the section's title, and preserve in the section all the
3801 substance and tone of each of the contributor acknowledgements
3802 and/or dedications given therein.@*
3803 L. Preserve all the Invariant Sections of the Document,
3804 unaltered in their text and in their titles. Section numbers
3805 or the equivalent are not considered part of the section titles.@*
3806 M. Delete any section entitled ``Endorsements''. Such a section
3807 may not be included in the Modified Version.@*
3808 N. Do not retitle any existing section as ``Endorsements''
3809 or to conflict in title with any Invariant Section.@*
3811 If the Modified Version includes new front-matter sections or
3812 appendices that qualify as Secondary Sections and contain no material
3813 copied from the Document, you may at your option designate some or all
3814 of these sections as invariant. To do this, add their titles to the
3815 list of Invariant Sections in the Modified Version's license notice.
3816 These titles must be distinct from any other section titles.
3818 You may add a section entitled ``Endorsements'', provided it contains
3819 nothing but endorsements of your Modified Version by various
3820 parties--for example, statements of peer review or that the text has
3821 been approved by an organization as the authoritative definition of a
3824 You may add a passage of up to five words as a Front-Cover Text, and a
3825 passage of up to 25 words as a Back-Cover Text, to the end of the list
3826 of Cover Texts in the Modified Version. Only one passage of
3827 Front-Cover Text and one of Back-Cover Text may be added by (or
3828 through arrangements made by) any one entity. If the Document already
3829 includes a cover text for the same cover, previously added by you or
3830 by arrangement made by the same entity you are acting on behalf of,
3831 you may not add another; but you may replace the old one, on explicit
3832 permission from the previous publisher that added the old one.
3834 The author(s) and publisher(s) of the Document do not by this License
3835 give permission to use their names for publicity for or to assert or
3836 imply endorsement of any Modified Version.
3841 You may combine the Document with other documents released under this
3842 License, under the terms defined in section 4 above for modified
3843 versions, provided that you include in the combination all of the
3844 Invariant Sections of all of the original documents, unmodified, and
3845 list them all as Invariant Sections of your combined work in its
3848 The combined work need only contain one copy of this License, and
3849 multiple identical Invariant Sections may be replaced with a single
3850 copy. If there are multiple Invariant Sections with the same name but
3851 different contents, make the title of each such section unique by
3852 adding at the end of it, in parentheses, the name of the original
3853 author or publisher of that section if known, or else a unique number.
3854 Make the same adjustment to the section titles in the list of
3855 Invariant Sections in the license notice of the combined work.
3857 In the combination, you must combine any sections entitled ``History''
3858 in the various original documents, forming one section entitled
3859 ``History''; likewise combine any sections entitled ``Acknowledgements'',
3860 and any sections entitled ``Dedications''. You must delete all sections
3861 entitled ``Endorsements.''
3864 COLLECTIONS OF DOCUMENTS
3866 You may make a collection consisting of the Document and other documents
3867 released under this License, and replace the individual copies of this
3868 License in the various documents with a single copy that is included in
3869 the collection, provided that you follow the rules of this License for
3870 verbatim copying of each of the documents in all other respects.
3872 You may extract a single document from such a collection, and distribute
3873 it individually under this License, provided you insert a copy of this
3874 License into the extracted document, and follow this License in all
3875 other respects regarding verbatim copying of that document.
3878 AGGREGATION WITH INDEPENDENT WORKS
3880 A compilation of the Document or its derivatives with other separate
3881 and independent documents or works, in or on a volume of a storage or
3882 distribution medium, does not as a whole count as a Modified Version
3883 of the Document, provided no compilation copyright is claimed for the
3884 compilation. Such a compilation is called an ``aggregate'', and this
3885 License does not apply to the other self-contained works thus compiled
3886 with the Document, on account of their being thus compiled, if they
3887 are not themselves derivative works of the Document.
3889 If the Cover Text requirement of section 3 is applicable to these
3890 copies of the Document, then if the Document is less than one quarter
3891 of the entire aggregate, the Document's Cover Texts may be placed on
3892 covers that surround only the Document within the aggregate.
3893 Otherwise they must appear on covers around the whole aggregate.
3898 Translation is considered a kind of modification, so you may
3899 distribute translations of the Document under the terms of section 4.
3900 Replacing Invariant Sections with translations requires special
3901 permission from their copyright holders, but you may include
3902 translations of some or all Invariant Sections in addition to the
3903 original versions of these Invariant Sections. You may include a
3904 translation of this License provided that you also include the
3905 original English version of this License. In case of a disagreement
3906 between the translation and the original English version of this
3907 License, the original English version will prevail.
3912 You may not copy, modify, sublicense, or distribute the Document except
3913 as expressly provided for under this License. Any other attempt to
3914 copy, modify, sublicense or distribute the Document is void, and will
3915 automatically terminate your rights under this License. However,
3916 parties who have received copies, or rights, from you under this
3917 License will not have their licenses terminated so long as such
3918 parties remain in full compliance.
3921 FUTURE REVISIONS OF THIS LICENSE
3923 The Free Software Foundation may publish new, revised versions
3924 of the GNU Free Documentation License from time to time. Such new
3925 versions will be similar in spirit to the present version, but may
3926 differ in detail to address new problems or concerns. See
3927 http://www.gnu.org/copyleft/.
3929 Each version of the License is given a distinguishing version number.
3930 If the Document specifies that a particular numbered version of this
3931 License ``or any later version'' applies to it, you have the option of
3932 following the terms and conditions either of that specified version or
3933 of any later version that has been published (not as a draft) by the
3934 Free Software Foundation. If the Document does not specify a version
3935 number of this License, you may choose any version ever published (not
3936 as a draft) by the Free Software Foundation.
3940 @unnumberedsec ADDENDUM: How to use this License for your documents
3942 To use this License in a document you have written, include a copy of
3943 the License in the document and put the following copyright and
3944 license notices just after the title page:
3949 Copyright (C) @var{year} @var{your name}.
3950 Permission is granted to copy, distribute and/or modify this document
3951 under the terms of the GNU Free Documentation License, Version 1.1
3952 or any later version published by the Free Software Foundation;
3953 with the Invariant Sections being @var{list their titles}, with the
3954 Front-Cover Texts being @var{list}, and with the Back-Cover Texts being @var{list}.
3955 A copy of the license is included in the section entitled ``GNU
3956 Free Documentation License''.
3959 If you have no Invariant Sections, write ``with no Invariant Sections''
3960 instead of saying which ones are invariant. If you have no
3961 Front-Cover Texts, write ``no Front-Cover Texts'' instead of
3962 ``Front-Cover Texts being @var{list}''; likewise for Back-Cover Texts.
3964 If your document contains nontrivial examples of program code, we
3965 recommend releasing these examples in parallel under your choice of
3966 free software license, such as the GNU General Public License,
3967 to permit their use in free software.
3970 @node Concept Index, , Copying, Top
3971 @unnumbered Concept Index