1 \input texinfo @c -*-texinfo-*-
7 @settitle GNU Wget @value{VERSION} Manual
8 @c Disable the monstrous rectangles beside overfull hbox-es.
10 @c Use `odd' to print double-sided.
15 @c Remove this if you don't use A4 paper.
19 @c Title for man page. The weird way texi2pod.pl is written requires
20 @c the preceding @set.
22 @c man title Wget The non-interactive network downloader.
24 @dircategory Network Applications
26 * Wget: (wget). The non-interactive network downloader.
30 This file documents the the GNU Wget utility for downloading network
33 @c man begin COPYRIGHT
34 Copyright @copyright{} 1996, 1997, 1998, 2000, 2001, 2002, 2003, 2004, 2005
35 Free Software Foundation, Inc.
37 Permission is granted to make and distribute verbatim copies of
38 this manual provided the copyright notice and this permission notice
39 are preserved on all copies.
42 Permission is granted to process this file through TeX and print the
43 results, provided the printed document carries a copying permission
44 notice identical to this one except for the removal of this paragraph
45 (this paragraph not being relevant to the printed manual).
47 Permission is granted to copy, distribute and/or modify this document
48 under the terms of the GNU Free Documentation License, Version 1.1 or
49 any later version published by the Free Software Foundation; with the
50 Invariant Sections being ``GNU General Public License'' and ``GNU Free
51 Documentation License'', with no Front-Cover Texts, and with no
52 Back-Cover Texts. A copy of the license is included in the section
53 entitled ``GNU Free Documentation License''.
58 @title GNU Wget @value{VERSION}
59 @subtitle The non-interactive download utility
60 @subtitle Updated for Wget @value{VERSION}, @value{UPDATED}
61 @author by Hrvoje Nik@v{s}i@'{c} and the developers
65 Originally written by Hrvoje Niksic <hniksic@xemacs.org>.
68 GNU Info entry for @file{wget}.
73 @vskip 0pt plus 1filll
74 Copyright @copyright{} 1996, 1997, 1998, 2000, 2001, 2003, 2004, 2005,
75 Free Software Foundation, Inc.
77 Permission is granted to copy, distribute and/or modify this document
78 under the terms of the GNU Free Documentation License, Version 1.2 or
79 any later version published by the Free Software Foundation; with the
80 Invariant Sections being ``GNU General Public License'' and ``GNU Free
81 Documentation License'', with no Front-Cover Texts, and with no
82 Back-Cover Texts. A copy of the license is included in the section
83 entitled ``GNU Free Documentation License''.
88 @top Wget @value{VERSION}
90 This manual documents version @value{VERSION} of GNU Wget, the freely
91 available utility for network downloads.
93 Copyright @copyright{} 1996, 1997, 1998, 2000, 2001, 2003, 2004, 2005
94 Free Software Foundation, Inc.
97 * Overview:: Features of Wget.
98 * Invoking:: Wget command-line arguments.
99 * Recursive Download:: Downloading interlinked pages.
100 * Following Links:: The available methods of chasing links.
101 * Time-Stamping:: Mirroring according to time-stamps.
102 * Startup File:: Wget's initialization file.
103 * Examples:: Examples of usage.
104 * Various:: The stuff that doesn't fit anywhere else.
105 * Appendices:: Some useful references.
106 * Copying:: You may give out copies of Wget and of this manual.
107 * Concept Index:: Topics covered by this manual.
116 @c man begin DESCRIPTION
117 GNU Wget is a free utility for non-interactive download of files from
118 the Web. It supports @sc{http}, @sc{https}, and @sc{ftp} protocols, as
119 well as retrieval through @sc{http} proxies.
122 This chapter is a partial overview of Wget's features.
126 @c man begin DESCRIPTION
127 Wget is non-interactive, meaning that it can work in the background,
128 while the user is not logged on. This allows you to start a retrieval
129 and disconnect from the system, letting Wget finish the work. By
130 contrast, most of the Web browsers require constant user's presence,
131 which can be a great hindrance when transferring a lot of data.
137 @c man begin DESCRIPTION
141 @c man begin DESCRIPTION
142 Wget can follow links in @sc{html} and @sc{xhtml} pages and create local
143 versions of remote web sites, fully recreating the directory structure of
144 the original site. This is sometimes referred to as ``recursive
145 downloading.'' While doing that, Wget respects the Robot Exclusion
146 Standard (@file{/robots.txt}). Wget can be instructed to convert the
147 links in downloaded @sc{html} files to the local files for offline
153 File name wildcard matching and recursive mirroring of directories are
154 available when retrieving via @sc{ftp}. Wget can read the time-stamp
155 information given by both @sc{http} and @sc{ftp} servers, and store it
156 locally. Thus Wget can see if the remote file has changed since last
157 retrieval, and automatically retrieve the new version if it has. This
158 makes Wget suitable for mirroring of @sc{ftp} sites, as well as home
164 @c man begin DESCRIPTION
168 @c man begin DESCRIPTION
169 Wget has been designed for robustness over slow or unstable network
170 connections; if a download fails due to a network problem, it will
171 keep retrying until the whole file has been retrieved. If the server
172 supports regetting, it will instruct the server to continue the
173 download from where it left off.
178 Wget supports proxy servers, which can lighten the network load, speed
179 up retrieval and provide access behind firewalls. However, if you are
180 behind a firewall that requires that you use a socks style gateway,
181 you can get the socks library and build Wget with support for socks.
182 Wget uses the passive @sc{ftp} downloading by default, active @sc{ftp}
187 Wget supports IP version 6, the next generation of IP. IPv6 is
188 autodetected at compile-time, and can be disabled at either build or
189 run time. Binaries built with IPv6 support work well in both
190 IPv4-only and dual family environments.
194 Built-in features offer mechanisms to tune which links you wish to follow
195 (@pxref{Following Links}).
199 The progress of individual downloads is traced using a progress gauge.
200 Interactive downloads are tracked using a ``thermometer''-style gauge,
201 whereas non-interactive ones are traced with dots, each dot
202 representing a fixed amount of data received (1KB by default). Either
203 gauge can be customized to your preferences.
207 Most of the features are fully configurable, either through command line
208 options, or via the initialization file @file{.wgetrc} (@pxref{Startup
209 File}). Wget allows you to define @dfn{global} startup files
210 (@file{/usr/local/etc/wgetrc} by default) for site settings.
215 @item /usr/local/etc/wgetrc
216 Default location of the @dfn{global} startup file.
226 Finally, GNU Wget is free software. This means that everyone may use
227 it, redistribute it and/or modify it under the terms of the GNU General
228 Public License, as published by the Free Software Foundation
239 By default, Wget is very simple to invoke. The basic syntax is:
242 @c man begin SYNOPSIS
243 wget [@var{option}]@dots{} [@var{URL}]@dots{}
247 Wget will simply download all the @sc{url}s specified on the command
248 line. @var{URL} is a @dfn{Uniform Resource Locator}, as defined below.
250 However, you may wish to change some of the default parameters of
251 Wget. You can do it two ways: permanently, adding the appropriate
252 command to @file{.wgetrc} (@pxref{Startup File}), or specifying it on
258 * Basic Startup Options::
259 * Logging and Input File Options::
261 * Directory Options::
264 * Recursive Retrieval Options::
265 * Recursive Accept/Reject Options::
273 @dfn{URL} is an acronym for Uniform Resource Locator. A uniform
274 resource locator is a compact string representation for a resource
275 available via the Internet. Wget recognizes the @sc{url} syntax as per
276 @sc{rfc1738}. This is the most widely used form (square brackets denote
280 http://host[:port]/directory/file
281 ftp://host[:port]/directory/file
284 You can also encode your username and password within a @sc{url}:
287 ftp://user:password@@host/path
288 http://user:password@@host/path
291 Either @var{user} or @var{password}, or both, may be left out. If you
292 leave out either the @sc{http} username or password, no authentication
293 will be sent. If you leave out the @sc{ftp} username, @samp{anonymous}
294 will be used. If you leave out the @sc{ftp} password, your email
295 address will be supplied as a default password.@footnote{If you have a
296 @file{.netrc} file in your home directory, password will also be
299 @strong{Important Note}: if you specify a password-containing @sc{url}
300 on the command line, the username and password will be plainly visible
301 to all users on the system, by way of @code{ps}. On multi-user systems,
302 this is a big security risk. To work around it, use @code{wget -i -}
303 and feed the @sc{url}s to Wget's standard input, each on a separate
304 line, terminated by @kbd{C-d}.
306 You can encode unsafe characters in a @sc{url} as @samp{%xy}, @code{xy}
307 being the hexadecimal representation of the character's @sc{ascii}
308 value. Some common unsafe characters include @samp{%} (quoted as
309 @samp{%25}), @samp{:} (quoted as @samp{%3A}), and @samp{@@} (quoted as
310 @samp{%40}). Refer to @sc{rfc1738} for a comprehensive list of unsafe
313 Wget also supports the @code{type} feature for @sc{ftp} @sc{url}s. By
314 default, @sc{ftp} documents are retrieved in the binary mode (type
315 @samp{i}), which means that they are downloaded unchanged. Another
316 useful mode is the @samp{a} (@dfn{ASCII}) mode, which converts the line
317 delimiters between the different operating systems, and is thus useful
318 for text files. Here is an example:
321 ftp://host/directory/file;type=a
324 Two alternative variants of @sc{url} specification are also supported,
325 because of historical (hysterical?) reasons and their widespreaded use.
327 @sc{ftp}-only syntax (supported by @code{NcFTP}):
332 @sc{http}-only syntax (introduced by @code{Netscape}):
337 These two alternative forms are deprecated, and may cease being
338 supported in the future.
340 If you do not understand the difference between these notations, or do
341 not know which one to use, just use the plain ordinary format you use
342 with your favorite browser, like @code{Lynx} or @code{Netscape}.
345 @section Option Syntax
346 @cindex option syntax
347 @cindex syntax of options
349 Since Wget uses GNU getopts to process its arguments, every option has a
350 short form and a long form. Long options are more convenient to
351 remember, but take time to type. You may freely mix different option
352 styles, or specify options after the command-line arguments. Thus you
356 wget -r --tries=10 http://fly.srk.fer.hr/ -o log
359 The space between the option accepting an argument and the argument may
360 be omitted. Instead @samp{-o log} you can write @samp{-olog}.
362 You may put several options that do not require arguments together,
369 This is a complete equivalent of:
372 wget -d -r -c @var{URL}
375 Since the options can be specified after the arguments, you may
376 terminate them with @samp{--}. So the following will try to download
377 @sc{url} @samp{-x}, reporting failure to @file{log}:
383 The options that accept comma-separated lists all respect the convention
384 that specifying an empty list clears its value. This can be useful to
385 clear the @file{.wgetrc} settings. For instance, if your @file{.wgetrc}
386 sets @code{exclude_directories} to @file{/cgi-bin}, the following
387 example will first reset it, and then set it to exclude @file{/~nobody}
388 and @file{/~somebody}. You can also clear the lists in @file{.wgetrc}
389 (@pxref{Wgetrc Syntax}).
392 wget -X '' -X /~nobody,/~somebody
397 @node Basic Startup Options
398 @section Basic Startup Options
403 Display the version of Wget.
407 Print a help message describing all of Wget's command-line options.
411 Go to background immediately after startup. If no output file is
412 specified via the @samp{-o}, output is redirected to @file{wget-log}.
414 @cindex execute wgetrc command
415 @item -e @var{command}
416 @itemx --execute @var{command}
417 Execute @var{command} as if it were a part of @file{.wgetrc}
418 (@pxref{Startup File}). A command thus invoked will be executed
419 @emph{after} the commands in @file{.wgetrc}, thus taking precedence over
420 them. If you need to specify more than one wgetrc command, use multiple
421 instances of @samp{-e}.
425 @node Logging and Input File Options
426 @section Logging and Input File Options
431 @item -o @var{logfile}
432 @itemx --output-file=@var{logfile}
433 Log all messages to @var{logfile}. The messages are normally reported
436 @cindex append to log
437 @item -a @var{logfile}
438 @itemx --append-output=@var{logfile}
439 Append to @var{logfile}. This is the same as @samp{-o}, only it appends
440 to @var{logfile} instead of overwriting the old log file. If
441 @var{logfile} does not exist, a new file is created.
446 Turn on debug output, meaning various information important to the
447 developers of Wget if it does not work properly. Your system
448 administrator may have chosen to compile Wget without debug support, in
449 which case @samp{-d} will not work. Please note that compiling with
450 debug support is always safe---Wget compiled with the debug support will
451 @emph{not} print any debug info unless requested with @samp{-d}.
452 @xref{Reporting Bugs}, for more information on how to use @samp{-d} for
458 Turn off Wget's output.
463 Turn on verbose output, with all the available data. The default output
468 Non-verbose output---turn off verbose without being completely quiet
469 (use @samp{-q} for that), which means that error messages and basic
470 information still get printed.
474 @itemx --input-file=@var{file}
475 Read @sc{url}s from @var{file}, in which case no @sc{url}s need to be on
476 the command line. If there are @sc{url}s both on the command line and
477 in an input file, those on the command lines will be the first ones to
478 be retrieved. The @var{file} need not be an @sc{html} document (but no
479 harm if it is)---it is enough if the @sc{url}s are just listed
482 However, if you specify @samp{--force-html}, the document will be
483 regarded as @samp{html}. In that case you may have problems with
484 relative links, which you can solve either by adding @code{<base
485 href="@var{url}">} to the documents or by specifying
486 @samp{--base=@var{url}} on the command line.
491 When input is read from a file, force it to be treated as an @sc{html}
492 file. This enables you to retrieve relative links from existing
493 @sc{html} files on your local disk, by adding @code{<base
494 href="@var{url}">} to @sc{html}, or using the @samp{--base} command-line
497 @cindex base for relative links in input file
499 @itemx --base=@var{URL}
500 When used in conjunction with @samp{-F}, prepends @var{URL} to relative
501 links in the file specified by @samp{-i}.
504 @node Download Options
505 @section Download Options
508 @cindex bind() address
509 @cindex client IP address
510 @cindex IP address, client
511 @item --bind-address=@var{ADDRESS}
512 When making client TCP/IP connections, @code{bind()} to @var{ADDRESS} on
513 the local machine. @var{ADDRESS} may be specified as a hostname or IP
514 address. This option can be useful if your machine is bound to multiple
519 @cindex number of retries
520 @item -t @var{number}
521 @itemx --tries=@var{number}
522 Set number of retries to @var{number}. Specify 0 or @samp{inf} for
523 infinite retrying. The default is to retry 20 times, with the exception
524 of fatal errors like ``connection refused'' or ``not found'' (404),
525 which are not retried.
528 @itemx --output-document=@var{file}
529 The documents will not be written to the appropriate files, but all will
530 be concatenated together and written to @var{file}. If @var{file}
531 already exists, it will be overwritten. If the @var{file} is @samp{-},
532 the documents will be written to standard output (disabling @samp{-k}).
534 Note that a combination with @samp{-k} is only well-defined for downloading
537 @cindex clobbering, file
538 @cindex downloading multiple times
542 If a file is downloaded more than once in the same directory, Wget's
543 behavior depends on a few options, including @samp{-nc}. In certain
544 cases, the local file will be @dfn{clobbered}, or overwritten, upon
545 repeated download. In other cases it will be preserved.
547 When running Wget without @samp{-N}, @samp{-nc}, or @samp{-r},
548 downloading the same file in the same directory will result in the
549 original copy of @var{file} being preserved and the second copy being
550 named @samp{@var{file}.1}. If that file is downloaded yet again, the
551 third copy will be named @samp{@var{file}.2}, and so on. When
552 @samp{-nc} is specified, this behavior is suppressed, and Wget will
553 refuse to download newer copies of @samp{@var{file}}. Therefore,
554 ``@code{no-clobber}'' is actually a misnomer in this mode---it's not
555 clobbering that's prevented (as the numeric suffixes were already
556 preventing clobbering), but rather the multiple version saving that's
559 When running Wget with @samp{-r}, but without @samp{-N} or @samp{-nc},
560 re-downloading a file will result in the new copy simply overwriting the
561 old. Adding @samp{-nc} will prevent this behavior, instead causing the
562 original version to be preserved and any newer copies on the server to
565 When running Wget with @samp{-N}, with or without @samp{-r}, the
566 decision as to whether or not to download a newer copy of a file depends
567 on the local and remote timestamp and size of the file
568 (@pxref{Time-Stamping}). @samp{-nc} may not be specified at the same
571 Note that when @samp{-nc} is specified, files with the suffixes
572 @samp{.html} or @samp{.htm} will be loaded from the local disk and
573 parsed as if they had been retrieved from the Web.
575 @cindex continue retrieval
576 @cindex incomplete downloads
577 @cindex resume download
580 Continue getting a partially-downloaded file. This is useful when you
581 want to finish up a download started by a previous instance of Wget, or
582 by another program. For instance:
585 wget -c ftp://sunsite.doc.ic.ac.uk/ls-lR.Z
588 If there is a file named @file{ls-lR.Z} in the current directory, Wget
589 will assume that it is the first portion of the remote file, and will
590 ask the server to continue the retrieval from an offset equal to the
591 length of the local file.
593 Note that you don't need to specify this option if you just want the
594 current invocation of Wget to retry downloading a file should the
595 connection be lost midway through. This is the default behavior.
596 @samp{-c} only affects resumption of downloads started @emph{prior} to
597 this invocation of Wget, and whose local files are still sitting around.
599 Without @samp{-c}, the previous example would just download the remote
600 file to @file{ls-lR.Z.1}, leaving the truncated @file{ls-lR.Z} file
603 Beginning with Wget 1.7, if you use @samp{-c} on a non-empty file, and
604 it turns out that the server does not support continued downloading,
605 Wget will refuse to start the download from scratch, which would
606 effectively ruin existing contents. If you really want the download to
607 start from scratch, remove the file.
609 Also beginning with Wget 1.7, if you use @samp{-c} on a file which is of
610 equal size as the one on the server, Wget will refuse to download the
611 file and print an explanatory message. The same happens when the file
612 is smaller on the server than locally (presumably because it was changed
613 on the server since your last download attempt)---because ``continuing''
614 is not meaningful, no download occurs.
616 On the other side of the coin, while using @samp{-c}, any file that's
617 bigger on the server than locally will be considered an incomplete
618 download and only @code{(length(remote) - length(local))} bytes will be
619 downloaded and tacked onto the end of the local file. This behavior can
620 be desirable in certain cases---for instance, you can use @samp{wget -c}
621 to download just the new portion that's been appended to a data
622 collection or log file.
624 However, if the file is bigger on the server because it's been
625 @emph{changed}, as opposed to just @emph{appended} to, you'll end up
626 with a garbled file. Wget has no way of verifying that the local file
627 is really a valid prefix of the remote file. You need to be especially
628 careful of this when using @samp{-c} in conjunction with @samp{-r},
629 since every file will be considered as an "incomplete download" candidate.
631 Another instance where you'll get a garbled file if you try to use
632 @samp{-c} is if you have a lame @sc{http} proxy that inserts a
633 ``transfer interrupted'' string into the local file. In the future a
634 ``rollback'' option may be added to deal with this case.
636 Note that @samp{-c} only works with @sc{ftp} servers and with @sc{http}
637 servers that support the @code{Range} header.
639 @cindex progress indicator
641 @item --progress=@var{type}
642 Select the type of the progress indicator you wish to use. Legal
643 indicators are ``dot'' and ``bar''.
645 The ``bar'' indicator is used by default. It draws an @sc{ascii} progress
646 bar graphics (a.k.a ``thermometer'' display) indicating the status of
647 retrieval. If the output is not a TTY, the ``dot'' bar will be used by
650 Use @samp{--progress=dot} to switch to the ``dot'' display. It traces
651 the retrieval by printing dots on the screen, each dot representing a
652 fixed amount of downloaded data.
654 When using the dotted retrieval, you may also set the @dfn{style} by
655 specifying the type as @samp{dot:@var{style}}. Different styles assign
656 different meaning to one dot. With the @code{default} style each dot
657 represents 1K, there are ten dots in a cluster and 50 dots in a line.
658 The @code{binary} style has a more ``computer''-like orientation---8K
659 dots, 16-dots clusters and 48 dots per line (which makes for 384K
660 lines). The @code{mega} style is suitable for downloading very large
661 files---each dot represents 64K retrieved, there are eight dots in a
662 cluster, and 48 dots on each line (so each line contains 3M).
664 Note that you can set the default style using the @code{progress}
665 command in @file{.wgetrc}. That setting may be overridden from the
666 command line. The exception is that, when the output is not a TTY, the
667 ``dot'' progress will be favored over ``bar''. To force the bar output,
668 use @samp{--progress=bar:force}.
671 @itemx --timestamping
672 Turn on time-stamping. @xref{Time-Stamping}, for details.
674 @cindex server response, print
676 @itemx --server-response
677 Print the headers sent by @sc{http} servers and responses sent by
680 @cindex Wget as spider
683 When invoked with this option, Wget will behave as a Web @dfn{spider},
684 which means that it will not download the pages, just check that they
685 are there. For example, you can use Wget to check your bookmarks:
688 wget --spider --force-html -i bookmarks.html
691 This feature needs much more work for Wget to get close to the
692 functionality of real web spiders.
696 @itemx --timeout=@var{seconds}
697 Set the network timeout to @var{seconds} seconds. This is equivalent
698 to specifying @samp{--dns-timeout}, @samp{--connect-timeout}, and
699 @samp{--read-timeout}, all at the same time.
701 Whenever Wget connects to or reads from a remote host, it checks for a
702 timeout and aborts the operation if the time expires. This prevents
703 anomalous occurrences such as hanging reads or infinite connects. The
704 only timeout enabled by default is a 900-second timeout for reading.
705 Setting timeout to 0 disables checking for timeouts.
707 Unless you know what you are doing, it is best not to set any of the
708 timeout-related options.
712 @item --dns-timeout=@var{seconds}
713 Set the DNS lookup timeout to @var{seconds} seconds. DNS lookups that
714 don't complete within the specified time will fail. By default, there
715 is no timeout on DNS lookups, other than that implemented by system
718 @cindex connect timeout
719 @cindex timeout, connect
720 @item --connect-timeout=@var{seconds}
721 Set the connect timeout to @var{seconds} seconds. TCP connections that
722 take longer to establish will be aborted. By default, there is no
723 connect timeout, other than that implemented by system libraries.
726 @cindex timeout, read
727 @item --read-timeout=@var{seconds}
728 Set the read (and write) timeout to @var{seconds} seconds. Reads that
729 take longer will fail. The default value for read timeout is 900
732 @cindex bandwidth, limit
734 @cindex limit bandwidth
735 @item --limit-rate=@var{amount}
736 Limit the download speed to @var{amount} bytes per second. Amount may
737 be expressed in bytes, kilobytes with the @samp{k} suffix, or megabytes
738 with the @samp{m} suffix. For example, @samp{--limit-rate=20k} will
739 limit the retrieval rate to 20KB/s. This kind of thing is useful when,
740 for whatever reason, you don't want Wget to consume the entire available
743 Note that Wget implements the limiting by sleeping the appropriate
744 amount of time after a network read that took less time than specified
745 by the rate. Eventually this strategy causes the TCP transfer to slow
746 down to approximately the specified rate. However, it may take some
747 time for this balance to be achieved, so don't be surprised if limiting
748 the rate doesn't work well with very small files.
752 @item -w @var{seconds}
753 @itemx --wait=@var{seconds}
754 Wait the specified number of seconds between the retrievals. Use of
755 this option is recommended, as it lightens the server load by making the
756 requests less frequent. Instead of in seconds, the time can be
757 specified in minutes using the @code{m} suffix, in hours using @code{h}
758 suffix, or in days using @code{d} suffix.
760 Specifying a large value for this option is useful if the network or the
761 destination host is down, so that Wget can wait long enough to
762 reasonably expect the network error to be fixed before the retry.
764 @cindex retries, waiting between
765 @cindex waiting between retries
766 @item --waitretry=@var{seconds}
767 If you don't want Wget to wait between @emph{every} retrieval, but only
768 between retries of failed downloads, you can use this option. Wget will
769 use @dfn{linear backoff}, waiting 1 second after the first failure on a
770 given file, then waiting 2 seconds after the second failure on that
771 file, up to the maximum number of @var{seconds} you specify. Therefore,
772 a value of 10 will actually make Wget wait up to (1 + 2 + ... + 10) = 55
775 Note that this option is turned on by default in the global
781 Some web sites may perform log analysis to identify retrieval programs
782 such as Wget by looking for statistically significant similarities in
783 the time between requests. This option causes the time between requests
784 to vary between 0 and 2 * @var{wait} seconds, where @var{wait} was
785 specified using the @samp{--wait} option, in order to mask Wget's
786 presence from such analysis.
788 A recent article in a publication devoted to development on a popular
789 consumer platform provided code to perform this analysis on the fly.
790 Its author suggested blocking at the class C address level to ensure
791 automated retrieval programs were blocked despite changing DHCP-supplied
794 The @samp{--random-wait} option was inspired by this ill-advised
795 recommendation to block many unrelated users from a web site due to the
800 @itemx --proxy=on/off
801 Turn proxy support on or off. The proxy is on by default if the
802 appropriate environment variable is defined.
804 For more information about the use of proxies with Wget, @xref{Proxies}.
808 @itemx --quota=@var{quota}
809 Specify download quota for automatic retrievals. The value can be
810 specified in bytes (default), kilobytes (with @samp{k} suffix), or
811 megabytes (with @samp{m} suffix).
813 Note that quota will never affect downloading a single file. So if you
814 specify @samp{wget -Q10k ftp://wuarchive.wustl.edu/ls-lR.gz}, all of the
815 @file{ls-lR.gz} will be downloaded. The same goes even when several
816 @sc{url}s are specified on the command-line. However, quota is
817 respected when retrieving either recursively, or from an input file.
818 Thus you may safely type @samp{wget -Q2m -i sites}---download will be
819 aborted when the quota is exceeded.
821 Setting quota to 0 or to @samp{inf} unlimits the download quota.
824 @cindex caching of DNS lookups
826 Turn off caching of DNS lookups. Normally, Wget remembers the IP
827 addresses it looked up from DNS so it doesn't have to repeatedly
828 contact the DNS server for the same (typically small) set of hosts it
829 retrieves from. This cache exists in memory only; a new Wget run will
832 However, it has been reported that in some situations it is not
833 desirable to cache host names, even for the duration of a
834 short-running application like Wget. With this option Wget issues a
835 new DNS lookup (more precisely, a new call to @code{gethostbyname} or
836 @code{getaddrinfo}) each time it makes a new connection. Please note
837 that this option will @emph{not} affect caching that might be
838 performed by the resolving library or by an external caching layer,
841 If you don't understand exactly what this option does, you probably
844 @cindex file names, restrict
845 @cindex Windows file names
846 @item --restrict-file-names=@var{mode}
847 Change which characters found in remote URLs may show up in local file
848 names generated from those URLs. Characters that are @dfn{restricted}
849 by this option are escaped, i.e. replaced with @samp{%HH}, where
850 @samp{HH} is the hexadecimal number that corresponds to the restricted
853 By default, Wget escapes the characters that are not valid as part of
854 file names on your operating system, as well as control characters that
855 are typically unprintable. This option is useful for changing these
856 defaults, either because you are downloading to a non-native partition,
857 or because you want to disable escaping of the control characters.
859 When mode is set to ``unix'', Wget escapes the character @samp{/} and
860 the control characters in the ranges 0--31 and 128--159. This is the
861 default on Unix-like OS'es.
863 When mode is set to ``windows'', Wget escapes the characters @samp{\},
864 @samp{|}, @samp{/}, @samp{:}, @samp{?}, @samp{"}, @samp{*}, @samp{<},
865 @samp{>}, and the control characters in the ranges 0--31 and 128--159.
866 In addition to this, Wget in Windows mode uses @samp{+} instead of
867 @samp{:} to separate host and port in local file names, and uses
868 @samp{@@} instead of @samp{?} to separate the query portion of the file
869 name from the rest. Therefore, a URL that would be saved as
870 @samp{www.xemacs.org:4300/search.pl?input=blah} in Unix mode would be
871 saved as @samp{www.xemacs.org+4300/search.pl@@input=blah} in Windows
872 mode. This mode is the default on Windows.
874 If you append @samp{,nocontrol} to the mode, as in
875 @samp{unix,nocontrol}, escaping of the control characters is also
876 switched off. You can use @samp{--restrict-file-names=nocontrol} to
877 turn off escaping of control characters without affecting the choice of
878 the OS to use as file name restriction mode.
885 Force connecting to IPv4 or IPv6 addresses. With @samp{--inet4-only}
886 or @samp{-4}, Wget will only connect to IPv4 hosts, ignoring AAAA
887 records in DNS, and refusing to connect to IPv6 addresses specified in
888 URLs. Conversely, with @samp{--inet6-only} or @samp{-6}, Wget will
889 only connect to IPv6 hosts and ignore A records and IPv4 addresses.
891 Neither options should be needed normally. By default, an IPv6-aware
892 Wget will use the address family specified by the host's DNS record.
893 If the DNS specifies both an A record and an AAAA record, Wget will
894 try them in sequence until it finds one it can connect to.
896 These options can be used to deliberately force the use of IPv4 or
897 IPv6 address families on dual family systems, usually to aid debugging
898 or to deal with broken network configuration. Only one of
899 @samp{--inet6-only} and @samp{--inet4-only} may be specified in the
900 same command. Neither option is available in Wget compiled without
903 Note: the current implementation of the @samp{-6} switch allows IPv4
904 addresses mapped into IPv6 addresses to be connected to. This usage
905 is not intended to be condoned, and it might be removed in a later
909 @node Directory Options
910 @section Directory Options
914 @itemx --no-directories
915 Do not create a hierarchy of directories when retrieving recursively.
916 With this option turned on, all files will get saved to the current
917 directory, without clobbering (if a name shows up more than once, the
918 filenames will get extensions @samp{.n}).
921 @itemx --force-directories
922 The opposite of @samp{-nd}---create a hierarchy of directories, even if
923 one would not have been created otherwise. E.g. @samp{wget -x
924 http://fly.srk.fer.hr/robots.txt} will save the downloaded file to
925 @file{fly.srk.fer.hr/robots.txt}.
928 @itemx --no-host-directories
929 Disable generation of host-prefixed directories. By default, invoking
930 Wget with @samp{-r http://fly.srk.fer.hr/} will create a structure of
931 directories beginning with @file{fly.srk.fer.hr/}. This option disables
934 @item --protocol-directories
935 Use the protocol name as a directory component of local file names. For
936 example, with this option, @samp{wget -r http://@var{host}} will save to
937 @samp{http/@var{host}/...} rather than just to @samp{@var{host}/...}.
939 Disable generation of host-prefixed directories. By default, invoking
940 Wget with @samp{-r http://fly.srk.fer.hr/} will create a structure of
941 directories beginning with @file{fly.srk.fer.hr/}. This option disables
944 @cindex cut directories
945 @item --cut-dirs=@var{number}
946 Ignore @var{number} directory components. This is useful for getting a
947 fine-grained control over the directory where recursive retrieval will
950 Take, for example, the directory at
951 @samp{ftp://ftp.xemacs.org/pub/xemacs/}. If you retrieve it with
952 @samp{-r}, it will be saved locally under
953 @file{ftp.xemacs.org/pub/xemacs/}. While the @samp{-nH} option can
954 remove the @file{ftp.xemacs.org/} part, you are still stuck with
955 @file{pub/xemacs}. This is where @samp{--cut-dirs} comes in handy; it
956 makes Wget not ``see'' @var{number} remote directory components. Here
957 are several examples of how @samp{--cut-dirs} option works.
961 No options -> ftp.xemacs.org/pub/xemacs/
963 -nH --cut-dirs=1 -> xemacs/
964 -nH --cut-dirs=2 -> .
966 --cut-dirs=1 -> ftp.xemacs.org/xemacs/
971 If you just want to get rid of the directory structure, this option is
972 similar to a combination of @samp{-nd} and @samp{-P}. However, unlike
973 @samp{-nd}, @samp{--cut-dirs} does not lose with subdirectories---for
974 instance, with @samp{-nH --cut-dirs=1}, a @file{beta/} subdirectory will
975 be placed to @file{xemacs/beta}, as one would expect.
977 @cindex directory prefix
978 @item -P @var{prefix}
979 @itemx --directory-prefix=@var{prefix}
980 Set directory prefix to @var{prefix}. The @dfn{directory prefix} is the
981 directory where all other files and subdirectories will be saved to,
982 i.e. the top of the retrieval tree. The default is @samp{.} (the
987 @section HTTP Options
990 @cindex .html extension
992 @itemx --html-extension
993 If a file of type @samp{application/xhtml+xml} or @samp{text/html} is
994 downloaded and the URL does not end with the regexp
995 @samp{\.[Hh][Tt][Mm][Ll]?}, this option will cause the suffix @samp{.html}
996 to be appended to the local filename. This is useful, for instance, when
997 you're mirroring a remote site that uses @samp{.asp} pages, but you want
998 the mirrored pages to be viewable on your stock Apache server. Another
999 good use for this is when you're downloading CGI-generated materials. A URL
1000 like @samp{http://site.com/article.cgi?25} will be saved as
1001 @file{article.cgi?25.html}.
1003 Note that filenames changed in this way will be re-downloaded every time
1004 you re-mirror a site, because Wget can't tell that the local
1005 @file{@var{X}.html} file corresponds to remote URL @samp{@var{X}} (since
1006 it doesn't yet know that the URL produces output of type
1007 @samp{text/html} or @samp{application/xhtml+xml}. To prevent this
1008 re-downloading, you must use @samp{-k} and @samp{-K} so that the original
1009 version of the file will be saved as @file{@var{X}.orig} (@pxref{Recursive
1010 Retrieval Options}).
1013 @cindex http password
1014 @cindex authentication
1015 @item --http-user=@var{user}
1016 @itemx --http-passwd=@var{password}
1017 Specify the username @var{user} and password @var{password} on an
1018 @sc{http} server. According to the type of the challenge, Wget will
1019 encode them using either the @code{basic} (insecure) or the
1020 @code{digest} authentication scheme.
1022 Another way to specify username and password is in the @sc{url} itself
1023 (@pxref{URL Format}). Either method reveals your password to anyone who
1024 bothers to run @code{ps}. To prevent the passwords from being seen,
1025 store them in @file{.wgetrc} or @file{.netrc}, and make sure to protect
1026 those files from other users with @code{chmod}. If the passwords are
1027 really important, do not leave them lying in those files either---edit
1028 the files and delete them after Wget has started the download.
1030 For more information about security issues with Wget, @xref{Security
1036 Disable server-side cache. In this case, Wget will send the remote
1037 server an appropriate directive (@samp{Pragma: no-cache}) to get the
1038 file from the remote service, rather than returning the cached version.
1039 This is especially useful for retrieving and flushing out-of-date
1040 documents on proxy servers.
1042 Caching is allowed by default.
1046 Disable the use of cookies. Cookies are a mechanism for maintaining
1047 server-side state. The server sends the client a cookie using the
1048 @code{Set-Cookie} header, and the client responds with the same cookie
1049 upon further requests. Since cookies allow the server owners to keep
1050 track of visitors and for sites to exchange this information, some
1051 consider them a breach of privacy. The default is to use cookies;
1052 however, @emph{storing} cookies is not on by default.
1054 @cindex loading cookies
1055 @cindex cookies, loading
1056 @item --load-cookies @var{file}
1057 Load cookies from @var{file} before the first HTTP retrieval.
1058 @var{file} is a textual file in the format originally used by Netscape's
1059 @file{cookies.txt} file.
1061 You will typically use this option when mirroring sites that require
1062 that you be logged in to access some or all of their content. The login
1063 process typically works by the web server issuing an @sc{http} cookie
1064 upon receiving and verifying your credentials. The cookie is then
1065 resent by the browser when accessing that part of the site, and so
1066 proves your identity.
1068 Mirroring such a site requires Wget to send the same cookies your
1069 browser sends when communicating with the site. This is achieved by
1070 @samp{--load-cookies}---simply point Wget to the location of the
1071 @file{cookies.txt} file, and it will send the same cookies your browser
1072 would send in the same situation. Different browsers keep textual
1073 cookie files in different locations:
1077 The cookies are in @file{~/.netscape/cookies.txt}.
1079 @item Mozilla and Netscape 6.x.
1080 Mozilla's cookie file is also named @file{cookies.txt}, located
1081 somewhere under @file{~/.mozilla}, in the directory of your profile.
1082 The full path usually ends up looking somewhat like
1083 @file{~/.mozilla/default/@var{some-weird-string}/cookies.txt}.
1085 @item Internet Explorer.
1086 You can produce a cookie file Wget can use by using the File menu,
1087 Import and Export, Export Cookies. This has been tested with Internet
1088 Explorer 5; it is not guaranteed to work with earlier versions.
1090 @item Other browsers.
1091 If you are using a different browser to create your cookies,
1092 @samp{--load-cookies} will only work if you can locate or produce a
1093 cookie file in the Netscape format that Wget expects.
1096 If you cannot use @samp{--load-cookies}, there might still be an
1097 alternative. If your browser supports a ``cookie manager'', you can use
1098 it to view the cookies used when accessing the site you're mirroring.
1099 Write down the name and value of the cookie, and manually instruct Wget
1100 to send those cookies, bypassing the ``official'' cookie support:
1103 wget --no-cookies --header "Cookie: @var{name}=@var{value}"
1106 @cindex saving cookies
1107 @cindex cookies, saving
1108 @item --save-cookies @var{file}
1109 Save cookies to @var{file} before exiting. This will not save cookies
1110 that have expired or that have no expiry time (so-called ``session
1111 cookies''), but also see @samp{--keep-session-cookies}.
1113 @cindex cookies, session
1114 @cindex session cookies
1115 @item --keep-session-cookies
1117 When specified, causes @samp{--save-cookies} to also save session
1118 cookies. Session cookies are normally not save because they are
1119 supposed to be forgotten when you exit the browser. Saving them is
1120 useful on sites that require you to log in or to visit the home page
1121 before you can access some pages. With this option, multiple Wget runs
1122 are considered a single browser session as far as the site is concerned.
1124 Since the cookie file format does not normally carry session cookies,
1125 Wget marks them with an expiry timestamp of 0. Wget's
1126 @samp{--load-cookies} recognizes those as session cookies, but it might
1127 confuse other browsers. Also note that cookies so loaded will be
1128 treated as other session cookies, which means that if you want
1129 @samp{--save-cookies} to preserve them again, you must use
1130 @samp{--keep-session-cookies} again.
1132 @cindex Content-Length, ignore
1133 @cindex ignore length
1134 @item --ignore-length
1135 Unfortunately, some @sc{http} servers (@sc{cgi} programs, to be more
1136 precise) send out bogus @code{Content-Length} headers, which makes Wget
1137 go wild, as it thinks not all the document was retrieved. You can spot
1138 this syndrome if Wget retries getting the same document again and again,
1139 each time claiming that the (otherwise normal) connection has closed on
1142 With this option, Wget will ignore the @code{Content-Length} header---as
1143 if it never existed.
1146 @item --header=@var{additional-header}
1147 Define an @var{additional-header} to be passed to the @sc{http} servers.
1148 Headers must contain a @samp{:} preceded by one or more non-blank
1149 characters, and must not contain newlines.
1151 You may define more than one additional header by specifying
1152 @samp{--header} more than once.
1156 wget --header='Accept-Charset: iso-8859-2' \
1157 --header='Accept-Language: hr' \
1158 http://fly.srk.fer.hr/
1162 Specification of an empty string as the header value will clear all
1163 previous user-defined headers.
1166 @cindex proxy password
1167 @cindex proxy authentication
1168 @item --proxy-user=@var{user}
1169 @itemx --proxy-passwd=@var{password}
1170 Specify the username @var{user} and password @var{password} for
1171 authentication on a proxy server. Wget will encode them using the
1172 @code{basic} authentication scheme.
1174 Security considerations similar to those with @samp{--http-passwd}
1175 pertain here as well.
1177 @cindex http referer
1178 @cindex referer, http
1179 @item --referer=@var{url}
1180 Include `Referer: @var{url}' header in HTTP request. Useful for
1181 retrieving documents with server-side processing that assume they are
1182 always being retrieved by interactive web browsers and only come out
1183 properly when Referer is set to one of the pages that point to them.
1185 @cindex server response, save
1186 @item --save-headers
1187 Save the headers sent by the @sc{http} server to the file, preceding the
1188 actual contents, with an empty line as the separator.
1191 @item -U @var{agent-string}
1192 @itemx --user-agent=@var{agent-string}
1193 Identify as @var{agent-string} to the @sc{http} server.
1195 The @sc{http} protocol allows the clients to identify themselves using a
1196 @code{User-Agent} header field. This enables distinguishing the
1197 @sc{www} software, usually for statistical purposes or for tracing of
1198 protocol violations. Wget normally identifies as
1199 @samp{Wget/@var{version}}, @var{version} being the current version
1202 However, some sites have been known to impose the policy of tailoring
1203 the output according to the @code{User-Agent}-supplied information.
1204 While conceptually this is not such a bad idea, it has been abused by
1205 servers denying information to clients other than @code{Mozilla} or
1206 Microsoft @code{Internet Explorer}. This option allows you to change
1207 the @code{User-Agent} line issued by Wget. Use of this option is
1208 discouraged, unless you really know what you are doing.
1211 @item --post-data=@var{string}
1212 @itemx --post-file=@var{file}
1213 Use POST as the method for all HTTP requests and send the specified data
1214 in the request body. @code{--post-data} sends @var{string} as data,
1215 whereas @code{--post-file} sends the contents of @var{file}. Other than
1216 that, they work in exactly the same way.
1218 Please be aware that Wget needs to know the size of the POST data in
1219 advance. Therefore the argument to @code{--post-file} must be a regular
1220 file; specifying a FIFO or something like @file{/dev/stdin} won't work.
1221 It's not quite clear how to work around this limitation inherent in
1222 HTTP/1.0. Although HTTP/1.1 introduces @dfn{chunked} transfer that
1223 doesn't require knowing the request length in advance, a client can't
1224 use chunked unless it knows it's talking to an HTTP/1.1 server. And it
1225 can't know that until it receives a response, which in turn requires the
1226 request to have been completed -- a chicken-and-egg problem.
1228 Note: if Wget is redirected after the POST request is completed, it will
1229 not send the POST data to the redirected URL. This is because URLs that
1230 process POST often respond with a redirection to a regular page
1231 (although that's technically disallowed), which does not desire or
1232 accept POST. It is not yet clear that this behavior is optimal; if it
1233 doesn't work out, it will be changed.
1235 This example shows how to log to a server using POST and then proceed to
1236 download the desired pages, presumably only accessible to authorized
1241 # @r{Log in to the server. This can be done only once.}
1242 wget --save-cookies cookies.txt \
1243 --post-data 'user=foo&password=bar' \
1244 http://server.com/auth.php
1246 # @r{Now grab the page or pages we care about.}
1247 wget --load-cookies cookies.txt \
1248 -p http://server.com/interesting/article.php
1254 @section FTP Options
1257 @cindex .listing files, removing
1258 @item --no-remove-listing
1259 Don't remove the temporary @file{.listing} files generated by @sc{ftp}
1260 retrievals. Normally, these files contain the raw directory listings
1261 received from @sc{ftp} servers. Not removing them can be useful for
1262 debugging purposes, or when you want to be able to easily check on the
1263 contents of remote server directories (e.g. to verify that a mirror
1264 you're running is complete).
1266 Note that even though Wget writes to a known filename for this file,
1267 this is not a security hole in the scenario of a user making
1268 @file{.listing} a symbolic link to @file{/etc/passwd} or something and
1269 asking @code{root} to run Wget in his or her directory. Depending on
1270 the options used, either Wget will refuse to write to @file{.listing},
1271 making the globbing/recursion/time-stamping operation fail, or the
1272 symbolic link will be deleted and replaced with the actual
1273 @file{.listing} file, or the listing will be written to a
1274 @file{.listing.@var{number}} file.
1276 Even though this situation isn't a problem, though, @code{root} should
1277 never run Wget in a non-trusted user's directory. A user could do
1278 something as simple as linking @file{index.html} to @file{/etc/passwd}
1279 and asking @code{root} to run Wget with @samp{-N} or @samp{-r} so the file
1280 will be overwritten.
1282 @cindex globbing, toggle
1284 Turn off @sc{ftp} globbing. Globbing refers to the use of shell-like
1285 special characters (@dfn{wildcards}), like @samp{*}, @samp{?}, @samp{[}
1286 and @samp{]} to retrieve more than one file from the same directory at
1290 wget ftp://gnjilux.srk.fer.hr/*.msg
1293 By default, globbing will be turned on if the @sc{url} contains a
1294 globbing character. This option may be used to turn globbing on or off
1297 You may have to quote the @sc{url} to protect it from being expanded by
1298 your shell. Globbing makes Wget look for a directory listing, which is
1299 system-specific. This is why it currently works only with Unix @sc{ftp}
1300 servers (and the ones emulating Unix @code{ls} output).
1303 @item --no-passive-ftp
1304 Disable the use of the @dfn{passive} FTP transfer mode. Passive FTP
1305 mandates that the client connect to the server to establish the data
1306 connection rather than the other way around.
1308 If the machine is connected to the Internet directly, both passive and
1309 active FTP should work equally well. Behind most firewall and NAT
1310 configurations passive FTP has a better chance of working. However,
1311 in some rare firewall configurations, active FTP actually works when
1312 passive FTP doesn't. If you suspect this to be the case, use this
1313 option, or set @code{passive_ftp=off} in your init file.
1315 @cindex symbolic links, retrieving
1316 @item --retr-symlinks
1317 Usually, when retrieving @sc{ftp} directories recursively and a symbolic
1318 link is encountered, the linked-to file is not downloaded. Instead, a
1319 matching symbolic link is created on the local filesystem. The
1320 pointed-to file will not be downloaded unless this recursive retrieval
1321 would have encountered it separately and downloaded it anyway.
1323 When @samp{--retr-symlinks} is specified, however, symbolic links are
1324 traversed and the pointed-to files are retrieved. At this time, this
1325 option does not cause Wget to traverse symlinks to directories and
1326 recurse through them, but in the future it should be enhanced to do
1329 Note that when retrieving a file (not a directory) because it was
1330 specified on the command-line, rather than because it was recursed to,
1331 this option has no effect. Symbolic links are always traversed in this
1334 @cindex Keep-Alive, turning off
1335 @cindex Persistent Connections, disabling
1336 @item --no-http-keep-alive
1337 Turn off the ``keep-alive'' feature for HTTP downloads. Normally, Wget
1338 asks the server to keep the connection open so that, when you download
1339 more than one document from the same server, they get transferred over
1340 the same TCP connection. This saves time and at the same time reduces
1341 the load on the server.
1343 This option is useful when, for some reason, persistent (keep-alive)
1344 connections don't work for you, for example due to a server bug or due
1345 to the inability of server-side scripts to cope with the connections.
1348 @node Recursive Retrieval Options
1349 @section Recursive Retrieval Options
1354 Turn on recursive retrieving. @xref{Recursive Download}, for more
1357 @item -l @var{depth}
1358 @itemx --level=@var{depth}
1359 Specify recursion maximum depth level @var{depth} (@pxref{Recursive
1360 Download}). The default maximum depth is 5.
1362 @cindex proxy filling
1363 @cindex delete after retrieval
1364 @cindex filling proxy cache
1365 @item --delete-after
1366 This option tells Wget to delete every single file it downloads,
1367 @emph{after} having done so. It is useful for pre-fetching popular
1368 pages through a proxy, e.g.:
1371 wget -r -nd --delete-after http://whatever.com/~popular/page/
1374 The @samp{-r} option is to retrieve recursively, and @samp{-nd} to not
1377 Note that @samp{--delete-after} deletes files on the local machine. It
1378 does not issue the @samp{DELE} command to remote FTP sites, for
1379 instance. Also note that when @samp{--delete-after} is specified,
1380 @samp{--convert-links} is ignored, so @samp{.orig} files are simply not
1381 created in the first place.
1383 @cindex conversion of links
1384 @cindex link conversion
1386 @itemx --convert-links
1387 After the download is complete, convert the links in the document to
1388 make them suitable for local viewing. This affects not only the visible
1389 hyperlinks, but any part of the document that links to external content,
1390 such as embedded images, links to style sheets, hyperlinks to non-@sc{html}
1393 Each link will be changed in one of the two ways:
1397 The links to files that have been downloaded by Wget will be changed to
1398 refer to the file they point to as a relative link.
1400 Example: if the downloaded file @file{/foo/doc.html} links to
1401 @file{/bar/img.gif}, also downloaded, then the link in @file{doc.html}
1402 will be modified to point to @samp{../bar/img.gif}. This kind of
1403 transformation works reliably for arbitrary combinations of directories.
1406 The links to files that have not been downloaded by Wget will be changed
1407 to include host name and absolute path of the location they point to.
1409 Example: if the downloaded file @file{/foo/doc.html} links to
1410 @file{/bar/img.gif} (or to @file{../bar/img.gif}), then the link in
1411 @file{doc.html} will be modified to point to
1412 @file{http://@var{hostname}/bar/img.gif}.
1415 Because of this, local browsing works reliably: if a linked file was
1416 downloaded, the link will refer to its local name; if it was not
1417 downloaded, the link will refer to its full Internet address rather than
1418 presenting a broken link. The fact that the former links are converted
1419 to relative links ensures that you can move the downloaded hierarchy to
1422 Note that only at the end of the download can Wget know which links have
1423 been downloaded. Because of that, the work done by @samp{-k} will be
1424 performed at the end of all the downloads.
1426 @cindex backing up converted files
1428 @itemx --backup-converted
1429 When converting a file, back up the original version with a @samp{.orig}
1430 suffix. Affects the behavior of @samp{-N} (@pxref{HTTP Time-Stamping
1435 Turn on options suitable for mirroring. This option turns on recursion
1436 and time-stamping, sets infinite recursion depth and keeps @sc{ftp}
1437 directory listings. It is currently equivalent to
1438 @samp{-r -N -l inf --no-remove-listing}.
1440 @cindex page requisites
1441 @cindex required images, downloading
1443 @itemx --page-requisites
1444 This option causes Wget to download all the files that are necessary to
1445 properly display a given @sc{html} page. This includes such things as
1446 inlined images, sounds, and referenced stylesheets.
1448 Ordinarily, when downloading a single @sc{html} page, any requisite documents
1449 that may be needed to display it properly are not downloaded. Using
1450 @samp{-r} together with @samp{-l} can help, but since Wget does not
1451 ordinarily distinguish between external and inlined documents, one is
1452 generally left with ``leaf documents'' that are missing their
1455 For instance, say document @file{1.html} contains an @code{<IMG>} tag
1456 referencing @file{1.gif} and an @code{<A>} tag pointing to external
1457 document @file{2.html}. Say that @file{2.html} is similar but that its
1458 image is @file{2.gif} and it links to @file{3.html}. Say this
1459 continues up to some arbitrarily high number.
1461 If one executes the command:
1464 wget -r -l 2 http://@var{site}/1.html
1467 then @file{1.html}, @file{1.gif}, @file{2.html}, @file{2.gif}, and
1468 @file{3.html} will be downloaded. As you can see, @file{3.html} is
1469 without its requisite @file{3.gif} because Wget is simply counting the
1470 number of hops (up to 2) away from @file{1.html} in order to determine
1471 where to stop the recursion. However, with this command:
1474 wget -r -l 2 -p http://@var{site}/1.html
1477 all the above files @emph{and} @file{3.html}'s requisite @file{3.gif}
1478 will be downloaded. Similarly,
1481 wget -r -l 1 -p http://@var{site}/1.html
1484 will cause @file{1.html}, @file{1.gif}, @file{2.html}, and @file{2.gif}
1485 to be downloaded. One might think that:
1488 wget -r -l 0 -p http://@var{site}/1.html
1491 would download just @file{1.html} and @file{1.gif}, but unfortunately
1492 this is not the case, because @samp{-l 0} is equivalent to
1493 @samp{-l inf}---that is, infinite recursion. To download a single @sc{html}
1494 page (or a handful of them, all specified on the command-line or in a
1495 @samp{-i} @sc{url} input file) and its (or their) requisites, simply leave off
1496 @samp{-r} and @samp{-l}:
1499 wget -p http://@var{site}/1.html
1502 Note that Wget will behave as if @samp{-r} had been specified, but only
1503 that single page and its requisites will be downloaded. Links from that
1504 page to external documents will not be followed. Actually, to download
1505 a single page and all its requisites (even if they exist on separate
1506 websites), and make sure the lot displays properly locally, this author
1507 likes to use a few options in addition to @samp{-p}:
1510 wget -E -H -k -K -p http://@var{site}/@var{document}
1513 To finish off this topic, it's worth knowing that Wget's idea of an
1514 external document link is any URL specified in an @code{<A>} tag, an
1515 @code{<AREA>} tag, or a @code{<LINK>} tag other than @code{<LINK
1518 @cindex @sc{html} comments
1519 @cindex comments, @sc{html}
1520 @item --strict-comments
1521 Turn on strict parsing of @sc{html} comments. The default is to terminate
1522 comments at the first occurrence of @samp{-->}.
1524 According to specifications, @sc{html} comments are expressed as @sc{sgml}
1525 @dfn{declarations}. Declaration is special markup that begins with
1526 @samp{<!} and ends with @samp{>}, such as @samp{<!DOCTYPE ...>}, that
1527 may contain comments between a pair of @samp{--} delimiters. @sc{html}
1528 comments are ``empty declarations'', @sc{sgml} declarations without any
1529 non-comment text. Therefore, @samp{<!--foo-->} is a valid comment, and
1530 so is @samp{<!--one-- --two-->}, but @samp{<!--1--2-->} is not.
1532 On the other hand, most @sc{html} writers don't perceive comments as anything
1533 other than text delimited with @samp{<!--} and @samp{-->}, which is not
1534 quite the same. For example, something like @samp{<!------------>}
1535 works as a valid comment as long as the number of dashes is a multiple
1536 of four (!). If not, the comment technically lasts until the next
1537 @samp{--}, which may be at the other end of the document. Because of
1538 this, many popular browsers completely ignore the specification and
1539 implement what users have come to expect: comments delimited with
1540 @samp{<!--} and @samp{-->}.
1542 Until version 1.9, Wget interpreted comments strictly, which resulted in
1543 missing links in many web pages that displayed fine in browsers, but had
1544 the misfortune of containing non-compliant comments. Beginning with
1545 version 1.9, Wget has joined the ranks of clients that implements
1546 ``naive'' comments, terminating each comment at the first occurrence of
1549 If, for whatever reason, you want strict comment parsing, use this
1550 option to turn it on.
1553 @node Recursive Accept/Reject Options
1554 @section Recursive Accept/Reject Options
1557 @item -A @var{acclist} --accept @var{acclist}
1558 @itemx -R @var{rejlist} --reject @var{rejlist}
1559 Specify comma-separated lists of file name suffixes or patterns to
1560 accept or reject (@pxref{Types of Files} for more details).
1562 @item -D @var{domain-list}
1563 @itemx --domains=@var{domain-list}
1564 Set domains to be followed. @var{domain-list} is a comma-separated list
1565 of domains. Note that it does @emph{not} turn on @samp{-H}.
1567 @item --exclude-domains @var{domain-list}
1568 Specify the domains that are @emph{not} to be followed.
1569 (@pxref{Spanning Hosts}).
1571 @cindex follow FTP links
1573 Follow @sc{ftp} links from @sc{html} documents. Without this option,
1574 Wget will ignore all the @sc{ftp} links.
1576 @cindex tag-based recursive pruning
1577 @item --follow-tags=@var{list}
1578 Wget has an internal table of @sc{html} tag / attribute pairs that it
1579 considers when looking for linked documents during a recursive
1580 retrieval. If a user wants only a subset of those tags to be
1581 considered, however, he or she should be specify such tags in a
1582 comma-separated @var{list} with this option.
1584 @item --ignore-tags=@var{list}
1585 This is the opposite of the @samp{--follow-tags} option. To skip
1586 certain @sc{html} tags when recursively looking for documents to download,
1587 specify them in a comma-separated @var{list}.
1589 In the past, this option was the best bet for downloading a single page
1590 and its requisites, using a command-line like:
1593 wget --ignore-tags=a,area -H -k -K -r http://@var{site}/@var{document}
1596 However, the author of this option came across a page with tags like
1597 @code{<LINK REL="home" HREF="/">} and came to the realization that
1598 specifying tags to ignore was not enough. One can't just tell Wget to
1599 ignore @code{<LINK>}, because then stylesheets will not be downloaded.
1600 Now the best bet for downloading a single page and its requisites is the
1601 dedicated @samp{--page-requisites} option.
1605 Enable spanning across hosts when doing recursive retrieving
1606 (@pxref{Spanning Hosts}).
1610 Follow relative links only. Useful for retrieving a specific home page
1611 without any distractions, not even those from the same hosts
1612 (@pxref{Relative Links}).
1615 @itemx --include-directories=@var{list}
1616 Specify a comma-separated list of directories you wish to follow when
1617 downloading (@pxref{Directory-Based Limits} for more details.) Elements
1618 of @var{list} may contain wildcards.
1621 @itemx --exclude-directories=@var{list}
1622 Specify a comma-separated list of directories you wish to exclude from
1623 download (@pxref{Directory-Based Limits} for more details.) Elements of
1624 @var{list} may contain wildcards.
1628 Do not ever ascend to the parent directory when retrieving recursively.
1629 This is a useful option, since it guarantees that only the files
1630 @emph{below} a certain hierarchy will be downloaded.
1631 @xref{Directory-Based Limits}, for more details.
1636 @node Recursive Download
1637 @chapter Recursive Download
1640 @cindex recursive download
1642 GNU Wget is capable of traversing parts of the Web (or a single
1643 @sc{http} or @sc{ftp} server), following links and directory structure.
1644 We refer to this as to @dfn{recursive retrieval}, or @dfn{recursion}.
1646 With @sc{http} @sc{url}s, Wget retrieves and parses the @sc{html} from
1647 the given @sc{url}, documents, retrieving the files the @sc{html}
1648 document was referring to, through markup like @code{href}, or
1649 @code{src}. If the freshly downloaded file is also of type
1650 @code{text/html} or @code{application/xhtml+xml}, it will be parsed and
1653 Recursive retrieval of @sc{http} and @sc{html} content is
1654 @dfn{breadth-first}. This means that Wget first downloads the requested
1655 @sc{html} document, then the documents linked from that document, then the
1656 documents linked by them, and so on. In other words, Wget first
1657 downloads the documents at depth 1, then those at depth 2, and so on
1658 until the specified maximum depth.
1660 The maximum @dfn{depth} to which the retrieval may descend is specified
1661 with the @samp{-l} option. The default maximum depth is five layers.
1663 When retrieving an @sc{ftp} @sc{url} recursively, Wget will retrieve all
1664 the data from the given directory tree (including the subdirectories up
1665 to the specified depth) on the remote server, creating its mirror image
1666 locally. @sc{ftp} retrieval is also limited by the @code{depth}
1667 parameter. Unlike @sc{http} recursion, @sc{ftp} recursion is performed
1670 By default, Wget will create a local directory tree, corresponding to
1671 the one found on the remote server.
1673 Recursive retrieving can find a number of applications, the most
1674 important of which is mirroring. It is also useful for @sc{www}
1675 presentations, and any other opportunities where slow network
1676 connections should be bypassed by storing the files locally.
1678 You should be warned that recursive downloads can overload the remote
1679 servers. Because of that, many administrators frown upon them and may
1680 ban access from your site if they detect very fast downloads of big
1681 amounts of content. When downloading from Internet servers, consider
1682 using the @samp{-w} option to introduce a delay between accesses to the
1683 server. The download will take a while longer, but the server
1684 administrator will not be alarmed by your rudeness.
1686 Of course, recursive download may cause problems on your machine. If
1687 left to run unchecked, it can easily fill up the disk. If downloading
1688 from local network, it can also take bandwidth on the system, as well as
1689 consume memory and CPU.
1691 Try to specify the criteria that match the kind of download you are
1692 trying to achieve. If you want to download only one page, use
1693 @samp{--page-requisites} without any additional recursion. If you want
1694 to download things under one directory, use @samp{-np} to avoid
1695 downloading things from other directories. If you want to download all
1696 the files from one directory, use @samp{-l 1} to make sure the recursion
1697 depth never exceeds one. @xref{Following Links}, for more information
1700 Recursive retrieval should be used with care. Don't say you were not
1703 @node Following Links
1704 @chapter Following Links
1706 @cindex following links
1708 When retrieving recursively, one does not wish to retrieve loads of
1709 unnecessary data. Most of the time the users bear in mind exactly what
1710 they want to download, and want Wget to follow only specific links.
1712 For example, if you wish to download the music archive from
1713 @samp{fly.srk.fer.hr}, you will not want to download all the home pages
1714 that happen to be referenced by an obscure part of the archive.
1716 Wget possesses several mechanisms that allows you to fine-tune which
1717 links it will follow.
1720 * Spanning Hosts:: (Un)limiting retrieval based on host name.
1721 * Types of Files:: Getting only certain files.
1722 * Directory-Based Limits:: Getting only certain directories.
1723 * Relative Links:: Follow relative links only.
1724 * FTP Links:: Following FTP links.
1727 @node Spanning Hosts
1728 @section Spanning Hosts
1729 @cindex spanning hosts
1730 @cindex hosts, spanning
1732 Wget's recursive retrieval normally refuses to visit hosts different
1733 than the one you specified on the command line. This is a reasonable
1734 default; without it, every retrieval would have the potential to turn
1735 your Wget into a small version of google.
1737 However, visiting different hosts, or @dfn{host spanning,} is sometimes
1738 a useful option. Maybe the images are served from a different server.
1739 Maybe you're mirroring a site that consists of pages interlinked between
1740 three servers. Maybe the server has two equivalent names, and the @sc{html}
1741 pages refer to both interchangeably.
1744 @item Span to any host---@samp{-H}
1746 The @samp{-H} option turns on host spanning, thus allowing Wget's
1747 recursive run to visit any host referenced by a link. Unless sufficient
1748 recursion-limiting criteria are applied depth, these foreign hosts will
1749 typically link to yet more hosts, and so on until Wget ends up sucking
1750 up much more data than you have intended.
1752 @item Limit spanning to certain domains---@samp{-D}
1754 The @samp{-D} option allows you to specify the domains that will be
1755 followed, thus limiting the recursion only to the hosts that belong to
1756 these domains. Obviously, this makes sense only in conjunction with
1757 @samp{-H}. A typical example would be downloading the contents of
1758 @samp{www.server.com}, but allowing downloads from
1759 @samp{images.server.com}, etc.:
1762 wget -rH -Dserver.com http://www.server.com/
1765 You can specify more than one address by separating them with a comma,
1766 e.g. @samp{-Ddomain1.com,domain2.com}.
1768 @item Keep download off certain domains---@samp{--exclude-domains}
1770 If there are domains you want to exclude specifically, you can do it
1771 with @samp{--exclude-domains}, which accepts the same type of arguments
1772 of @samp{-D}, but will @emph{exclude} all the listed domains. For
1773 example, if you want to download all the hosts from @samp{foo.edu}
1774 domain, with the exception of @samp{sunsite.foo.edu}, you can do it like
1778 wget -rH -Dfoo.edu --exclude-domains sunsite.foo.edu \
1784 @node Types of Files
1785 @section Types of Files
1786 @cindex types of files
1788 When downloading material from the web, you will often want to restrict
1789 the retrieval to only certain file types. For example, if you are
1790 interested in downloading @sc{gif}s, you will not be overjoyed to get
1791 loads of PostScript documents, and vice versa.
1793 Wget offers two options to deal with this problem. Each option
1794 description lists a short name, a long name, and the equivalent command
1797 @cindex accept wildcards
1798 @cindex accept suffixes
1799 @cindex wildcards, accept
1800 @cindex suffixes, accept
1802 @item -A @var{acclist}
1803 @itemx --accept @var{acclist}
1804 @itemx accept = @var{acclist}
1805 The argument to @samp{--accept} option is a list of file suffixes or
1806 patterns that Wget will download during recursive retrieval. A suffix
1807 is the ending part of a file, and consists of ``normal'' letters,
1808 e.g. @samp{gif} or @samp{.jpg}. A matching pattern contains shell-like
1809 wildcards, e.g. @samp{books*} or @samp{zelazny*196[0-9]*}.
1811 So, specifying @samp{wget -A gif,jpg} will make Wget download only the
1812 files ending with @samp{gif} or @samp{jpg}, i.e. @sc{gif}s and
1813 @sc{jpeg}s. On the other hand, @samp{wget -A "zelazny*196[0-9]*"} will
1814 download only files beginning with @samp{zelazny} and containing numbers
1815 from 1960 to 1969 anywhere within. Look up the manual of your shell for
1816 a description of how pattern matching works.
1818 Of course, any number of suffixes and patterns can be combined into a
1819 comma-separated list, and given as an argument to @samp{-A}.
1821 @cindex reject wildcards
1822 @cindex reject suffixes
1823 @cindex wildcards, reject
1824 @cindex suffixes, reject
1825 @item -R @var{rejlist}
1826 @itemx --reject @var{rejlist}
1827 @itemx reject = @var{rejlist}
1828 The @samp{--reject} option works the same way as @samp{--accept}, only
1829 its logic is the reverse; Wget will download all files @emph{except} the
1830 ones matching the suffixes (or patterns) in the list.
1832 So, if you want to download a whole page except for the cumbersome
1833 @sc{mpeg}s and @sc{.au} files, you can use @samp{wget -R mpg,mpeg,au}.
1834 Analogously, to download all files except the ones beginning with
1835 @samp{bjork}, use @samp{wget -R "bjork*"}. The quotes are to prevent
1836 expansion by the shell.
1839 The @samp{-A} and @samp{-R} options may be combined to achieve even
1840 better fine-tuning of which files to retrieve. E.g. @samp{wget -A
1841 "*zelazny*" -R .ps} will download all the files having @samp{zelazny} as
1842 a part of their name, but @emph{not} the PostScript files.
1844 Note that these two options do not affect the downloading of @sc{html}
1845 files; Wget must load all the @sc{html}s to know where to go at
1846 all---recursive retrieval would make no sense otherwise.
1848 @node Directory-Based Limits
1849 @section Directory-Based Limits
1851 @cindex directory limits
1853 Regardless of other link-following facilities, it is often useful to
1854 place the restriction of what files to retrieve based on the directories
1855 those files are placed in. There can be many reasons for this---the
1856 home pages may be organized in a reasonable directory structure; or some
1857 directories may contain useless information, e.g. @file{/cgi-bin} or
1858 @file{/dev} directories.
1860 Wget offers three different options to deal with this requirement. Each
1861 option description lists a short name, a long name, and the equivalent
1862 command in @file{.wgetrc}.
1864 @cindex directories, include
1865 @cindex include directories
1866 @cindex accept directories
1869 @itemx --include @var{list}
1870 @itemx include_directories = @var{list}
1871 @samp{-I} option accepts a comma-separated list of directories included
1872 in the retrieval. Any other directories will simply be ignored. The
1873 directories are absolute paths.
1875 So, if you wish to download from @samp{http://host/people/bozo/}
1876 following only links to bozo's colleagues in the @file{/people}
1877 directory and the bogus scripts in @file{/cgi-bin}, you can specify:
1880 wget -I /people,/cgi-bin http://host/people/bozo/
1883 @cindex directories, exclude
1884 @cindex exclude directories
1885 @cindex reject directories
1887 @itemx --exclude @var{list}
1888 @itemx exclude_directories = @var{list}
1889 @samp{-X} option is exactly the reverse of @samp{-I}---this is a list of
1890 directories @emph{excluded} from the download. E.g. if you do not want
1891 Wget to download things from @file{/cgi-bin} directory, specify @samp{-X
1892 /cgi-bin} on the command line.
1894 The same as with @samp{-A}/@samp{-R}, these two options can be combined
1895 to get a better fine-tuning of downloading subdirectories. E.g. if you
1896 want to load all the files from @file{/pub} hierarchy except for
1897 @file{/pub/worthless}, specify @samp{-I/pub -X/pub/worthless}.
1902 @itemx no_parent = on
1903 The simplest, and often very useful way of limiting directories is
1904 disallowing retrieval of the links that refer to the hierarchy
1905 @dfn{above} than the beginning directory, i.e. disallowing ascent to the
1906 parent directory/directories.
1908 The @samp{--no-parent} option (short @samp{-np}) is useful in this case.
1909 Using it guarantees that you will never leave the existing hierarchy.
1910 Supposing you issue Wget with:
1913 wget -r --no-parent http://somehost/~luzer/my-archive/
1916 You may rest assured that none of the references to
1917 @file{/~his-girls-homepage/} or @file{/~luzer/all-my-mpegs/} will be
1918 followed. Only the archive you are interested in will be downloaded.
1919 Essentially, @samp{--no-parent} is similar to
1920 @samp{-I/~luzer/my-archive}, only it handles redirections in a more
1921 intelligent fashion.
1924 @node Relative Links
1925 @section Relative Links
1926 @cindex relative links
1928 When @samp{-L} is turned on, only the relative links are ever followed.
1929 Relative links are here defined those that do not refer to the web
1930 server root. For example, these links are relative:
1934 <a href="foo/bar.gif">
1935 <a href="../foo/bar.gif">
1938 These links are not relative:
1942 <a href="/foo/bar.gif">
1943 <a href="http://www.server.com/foo/bar.gif">
1946 Using this option guarantees that recursive retrieval will not span
1947 hosts, even without @samp{-H}. In simple cases it also allows downloads
1948 to ``just work'' without having to convert links.
1950 This option is probably not very useful and might be removed in a future
1954 @section Following FTP Links
1955 @cindex following ftp links
1957 The rules for @sc{ftp} are somewhat specific, as it is necessary for
1958 them to be. @sc{ftp} links in @sc{html} documents are often included
1959 for purposes of reference, and it is often inconvenient to download them
1962 To have @sc{ftp} links followed from @sc{html} documents, you need to
1963 specify the @samp{--follow-ftp} option. Having done that, @sc{ftp}
1964 links will span hosts regardless of @samp{-H} setting. This is logical,
1965 as @sc{ftp} links rarely point to the same host where the @sc{http}
1966 server resides. For similar reasons, the @samp{-L} options has no
1967 effect on such downloads. On the other hand, domain acceptance
1968 (@samp{-D}) and suffix rules (@samp{-A} and @samp{-R}) apply normally.
1970 Also note that followed links to @sc{ftp} directories will not be
1971 retrieved recursively further.
1974 @chapter Time-Stamping
1975 @cindex time-stamping
1976 @cindex timestamping
1977 @cindex updating the archives
1978 @cindex incremental updating
1980 One of the most important aspects of mirroring information from the
1981 Internet is updating your archives.
1983 Downloading the whole archive again and again, just to replace a few
1984 changed files is expensive, both in terms of wasted bandwidth and money,
1985 and the time to do the update. This is why all the mirroring tools
1986 offer the option of incremental updating.
1988 Such an updating mechanism means that the remote server is scanned in
1989 search of @dfn{new} files. Only those new files will be downloaded in
1990 the place of the old ones.
1992 A file is considered new if one of these two conditions are met:
1996 A file of that name does not already exist locally.
1999 A file of that name does exist, but the remote file was modified more
2000 recently than the local file.
2003 To implement this, the program needs to be aware of the time of last
2004 modification of both local and remote files. We call this information the
2005 @dfn{time-stamp} of a file.
2007 The time-stamping in GNU Wget is turned on using @samp{--timestamping}
2008 (@samp{-N}) option, or through @code{timestamping = on} directive in
2009 @file{.wgetrc}. With this option, for each file it intends to download,
2010 Wget will check whether a local file of the same name exists. If it
2011 does, and the remote file is older, Wget will not download it.
2013 If the local file does not exist, or the sizes of the files do not
2014 match, Wget will download the remote file no matter what the time-stamps
2018 * Time-Stamping Usage::
2019 * HTTP Time-Stamping Internals::
2020 * FTP Time-Stamping Internals::
2023 @node Time-Stamping Usage
2024 @section Time-Stamping Usage
2025 @cindex time-stamping usage
2026 @cindex usage, time-stamping
2028 The usage of time-stamping is simple. Say you would like to download a
2029 file so that it keeps its date of modification.
2032 wget -S http://www.gnu.ai.mit.edu/
2035 A simple @code{ls -l} shows that the time stamp on the local file equals
2036 the state of the @code{Last-Modified} header, as returned by the server.
2037 As you can see, the time-stamping info is preserved locally, even
2038 without @samp{-N} (at least for @sc{http}).
2040 Several days later, you would like Wget to check if the remote file has
2041 changed, and download it if it has.
2044 wget -N http://www.gnu.ai.mit.edu/
2047 Wget will ask the server for the last-modified date. If the local file
2048 has the same timestamp as the server, or a newer one, the remote file
2049 will not be re-fetched. However, if the remote file is more recent,
2050 Wget will proceed to fetch it.
2052 The same goes for @sc{ftp}. For example:
2055 wget "ftp://ftp.ifi.uio.no/pub/emacs/gnus/*"
2058 (The quotes around that URL are to prevent the shell from trying to
2059 interpret the @samp{*}.)
2061 After download, a local directory listing will show that the timestamps
2062 match those on the remote server. Reissuing the command with @samp{-N}
2063 will make Wget re-fetch @emph{only} the files that have been modified
2064 since the last download.
2066 If you wished to mirror the GNU archive every week, you would use a
2067 command like the following, weekly:
2070 wget --timestamping -r ftp://ftp.gnu.org/pub/gnu/
2073 Note that time-stamping will only work for files for which the server
2074 gives a timestamp. For @sc{http}, this depends on getting a
2075 @code{Last-Modified} header. For @sc{ftp}, this depends on getting a
2076 directory listing with dates in a format that Wget can parse
2077 (@pxref{FTP Time-Stamping Internals}).
2079 @node HTTP Time-Stamping Internals
2080 @section HTTP Time-Stamping Internals
2081 @cindex http time-stamping
2083 Time-stamping in @sc{http} is implemented by checking of the
2084 @code{Last-Modified} header. If you wish to retrieve the file
2085 @file{foo.html} through @sc{http}, Wget will check whether
2086 @file{foo.html} exists locally. If it doesn't, @file{foo.html} will be
2087 retrieved unconditionally.
2089 If the file does exist locally, Wget will first check its local
2090 time-stamp (similar to the way @code{ls -l} checks it), and then send a
2091 @code{HEAD} request to the remote server, demanding the information on
2094 The @code{Last-Modified} header is examined to find which file was
2095 modified more recently (which makes it ``newer''). If the remote file
2096 is newer, it will be downloaded; if it is older, Wget will give
2097 up.@footnote{As an additional check, Wget will look at the
2098 @code{Content-Length} header, and compare the sizes; if they are not the
2099 same, the remote file will be downloaded no matter what the time-stamp
2102 When @samp{--backup-converted} (@samp{-K}) is specified in conjunction
2103 with @samp{-N}, server file @samp{@var{X}} is compared to local file
2104 @samp{@var{X}.orig}, if extant, rather than being compared to local file
2105 @samp{@var{X}}, which will always differ if it's been converted by
2106 @samp{--convert-links} (@samp{-k}).
2108 Arguably, @sc{http} time-stamping should be implemented using the
2109 @code{If-Modified-Since} request.
2111 @node FTP Time-Stamping Internals
2112 @section FTP Time-Stamping Internals
2113 @cindex ftp time-stamping
2115 In theory, @sc{ftp} time-stamping works much the same as @sc{http}, only
2116 @sc{ftp} has no headers---time-stamps must be ferreted out of directory
2119 If an @sc{ftp} download is recursive or uses globbing, Wget will use the
2120 @sc{ftp} @code{LIST} command to get a file listing for the directory
2121 containing the desired file(s). It will try to analyze the listing,
2122 treating it like Unix @code{ls -l} output, extracting the time-stamps.
2123 The rest is exactly the same as for @sc{http}. Note that when
2124 retrieving individual files from an @sc{ftp} server without using
2125 globbing or recursion, listing files will not be downloaded (and thus
2126 files will not be time-stamped) unless @samp{-N} is specified.
2128 Assumption that every directory listing is a Unix-style listing may
2129 sound extremely constraining, but in practice it is not, as many
2130 non-Unix @sc{ftp} servers use the Unixoid listing format because most
2131 (all?) of the clients understand it. Bear in mind that @sc{rfc959}
2132 defines no standard way to get a file list, let alone the time-stamps.
2133 We can only hope that a future standard will define this.
2135 Another non-standard solution includes the use of @code{MDTM} command
2136 that is supported by some @sc{ftp} servers (including the popular
2137 @code{wu-ftpd}), which returns the exact time of the specified file.
2138 Wget may support this command in the future.
2141 @chapter Startup File
2142 @cindex startup file
2148 Once you know how to change default settings of Wget through command
2149 line arguments, you may wish to make some of those settings permanent.
2150 You can do that in a convenient way by creating the Wget startup
2151 file---@file{.wgetrc}.
2153 Besides @file{.wgetrc} is the ``main'' initialization file, it is
2154 convenient to have a special facility for storing passwords. Thus Wget
2155 reads and interprets the contents of @file{$HOME/.netrc}, if it finds
2156 it. You can find @file{.netrc} format in your system manuals.
2158 Wget reads @file{.wgetrc} upon startup, recognizing a limited set of
2162 * Wgetrc Location:: Location of various wgetrc files.
2163 * Wgetrc Syntax:: Syntax of wgetrc.
2164 * Wgetrc Commands:: List of available commands.
2165 * Sample Wgetrc:: A wgetrc example.
2168 @node Wgetrc Location
2169 @section Wgetrc Location
2170 @cindex wgetrc location
2171 @cindex location of wgetrc
2173 When initializing, Wget will look for a @dfn{global} startup file,
2174 @file{/usr/local/etc/wgetrc} by default (or some prefix other than
2175 @file{/usr/local}, if Wget was not installed there) and read commands
2176 from there, if it exists.
2178 Then it will look for the user's file. If the environmental variable
2179 @code{WGETRC} is set, Wget will try to load that file. Failing that, no
2180 further attempts will be made.
2182 If @code{WGETRC} is not set, Wget will try to load @file{$HOME/.wgetrc}.
2184 The fact that user's settings are loaded after the system-wide ones
2185 means that in case of collision user's wgetrc @emph{overrides} the
2186 system-wide wgetrc (in @file{/usr/local/etc/wgetrc} by default).
2187 Fascist admins, away!
2190 @section Wgetrc Syntax
2191 @cindex wgetrc syntax
2192 @cindex syntax of wgetrc
2194 The syntax of a wgetrc command is simple:
2200 The @dfn{variable} will also be called @dfn{command}. Valid
2201 @dfn{values} are different for different commands.
2203 The commands are case-insensitive and underscore-insensitive. Thus
2204 @samp{DIr__PrefiX} is the same as @samp{dirprefix}. Empty lines, lines
2205 beginning with @samp{#} and lines containing white-space only are
2208 Commands that expect a comma-separated list will clear the list on an
2209 empty command. So, if you wish to reset the rejection list specified in
2210 global @file{wgetrc}, you can do it with:
2216 @node Wgetrc Commands
2217 @section Wgetrc Commands
2218 @cindex wgetrc commands
2220 The complete set of commands is listed below. Legal values are listed
2221 after the @samp{=}. Simple Boolean values can be set or unset using
2222 @samp{on} and @samp{off} or @samp{1} and @samp{0}. A fancier kind of
2223 Boolean allowed in some cases is the @dfn{lockable Boolean}, which may
2224 be set to @samp{on}, @samp{off}, @samp{always}, or @samp{never}. If an
2225 option is set to @samp{always} or @samp{never}, that value will be
2226 locked in for the duration of the Wget invocation---command-line options
2229 Some commands take pseudo-arbitrary values. @var{address} values can be
2230 hostnames or dotted-quad IP addresses. @var{n} can be any positive
2231 integer, or @samp{inf} for infinity, where appropriate. @var{string}
2232 values can be any non-empty string.
2234 Most of these commands have direct command-line equivalents. Also, any
2235 wgetrc command can be specified on the command line using the
2236 @samp{--execute} switch (@pxref{Basic Startup Options}.)
2239 @item accept/reject = @var{string}
2240 Same as @samp{-A}/@samp{-R} (@pxref{Types of Files}).
2242 @item add_hostdir = on/off
2243 Enable/disable host-prefixed file names. @samp{-nH} disables it.
2245 @item continue = on/off
2246 If set to on, force continuation of preexistent partially retrieved
2247 files. See @samp{-c} before setting it.
2249 @item background = on/off
2250 Enable/disable going to background---the same as @samp{-b} (which
2253 @item backup_converted = on/off
2254 Enable/disable saving pre-converted files with the suffix
2255 @samp{.orig}---the same as @samp{-K} (which enables it).
2257 @c @item backups = @var{number}
2258 @c #### Document me!
2260 @item base = @var{string}
2261 Consider relative @sc{url}s in @sc{url} input files forced to be
2262 interpreted as @sc{html} as being relative to @var{string}---the same as
2265 @item bind_address = @var{address}
2266 Bind to @var{address}, like the @samp{--bind-address} option.
2268 @item cache = on/off
2269 When set to off, disallow server-caching. See the @samp{--no-cache}
2272 @item convert_links = on/off
2273 Convert non-relative links locally. The same as @samp{-k}.
2275 @item cookies = on/off
2276 When set to off, disallow cookies. See the @samp{--cookies} option.
2278 @item load_cookies = @var{file}
2279 Load cookies from @var{file}. See @samp{--load-cookies}.
2281 @item save_cookies = @var{file}
2282 Save cookies to @var{file}. See @samp{--save-cookies}.
2284 @item connect_timeout = @var{n}
2285 Set the connect timeout---the same as @samp{--connect-timeout}.
2287 @item cut_dirs = @var{n}
2288 Ignore @var{n} remote directory components.
2290 @item debug = on/off
2291 Debug mode, same as @samp{-d}.
2293 @item delete_after = on/off
2294 Delete after download---the same as @samp{--delete-after}.
2296 @item dir_prefix = @var{string}
2297 Top of directory tree---the same as @samp{-P}.
2299 @item dirstruct = on/off
2300 Turning dirstruct on or off---the same as @samp{-x} or @samp{-nd},
2303 @item dns_cache = on/off
2304 Turn DNS caching on/off. Since DNS caching is on by default, this
2305 option is normally used to turn it off. Same as @samp{--dns-cache}.
2307 @item dns_timeout = @var{n}
2308 Set the DNS timeout---the same as @samp{--dns-timeout}.
2310 @item domains = @var{string}
2311 Same as @samp{-D} (@pxref{Spanning Hosts}).
2313 @item dot_bytes = @var{n}
2314 Specify the number of bytes ``contained'' in a dot, as seen throughout
2315 the retrieval (1024 by default). You can postfix the value with
2316 @samp{k} or @samp{m}, representing kilobytes and megabytes,
2317 respectively. With dot settings you can tailor the dot retrieval to
2318 suit your needs, or you can use the predefined @dfn{styles}
2319 (@pxref{Download Options}).
2321 @item dots_in_line = @var{n}
2322 Specify the number of dots that will be printed in each line throughout
2323 the retrieval (50 by default).
2325 @item dot_spacing = @var{n}
2326 Specify the number of dots in a single cluster (10 by default).
2328 @item exclude_directories = @var{string}
2329 Specify a comma-separated list of directories you wish to exclude from
2330 download---the same as @samp{-X} (@pxref{Directory-Based Limits}).
2332 @item exclude_domains = @var{string}
2333 Same as @samp{--exclude-domains} (@pxref{Spanning Hosts}).
2335 @item follow_ftp = on/off
2336 Follow @sc{ftp} links from @sc{html} documents---the same as
2337 @samp{--follow-ftp}.
2339 @item follow_tags = @var{string}
2340 Only follow certain @sc{html} tags when doing a recursive retrieval, just like
2341 @samp{--follow-tags}.
2343 @item force_html = on/off
2344 If set to on, force the input filename to be regarded as an @sc{html}
2345 document---the same as @samp{-F}.
2347 @item ftp_proxy = @var{string}
2348 Use @var{string} as @sc{ftp} proxy, instead of the one specified in
2352 Turn globbing on/off---the same as @samp{--glob} and @samp{--no-glob}.
2354 @item header = @var{string}
2355 Define an additional header, like @samp{--header}.
2357 @item html_extension = on/off
2358 Add a @samp{.html} extension to @samp{text/html} or
2359 @samp{application/xhtml+xml} files without it, like
2362 @item http_keep_alive = on/off
2363 Turn the keep-alive feature on or off (defaults to on). The same as
2364 `--http-keep-alive'.
2366 @item http_passwd = @var{string}
2367 Set @sc{http} password.
2369 @item http_proxy = @var{string}
2370 Use @var{string} as @sc{http} proxy, instead of the one specified in
2373 @item http_user = @var{string}
2374 Set @sc{http} user to @var{string}.
2376 @item ignore_length = on/off
2377 When set to on, ignore @code{Content-Length} header; the same as
2378 @samp{--ignore-length}.
2380 @item ignore_tags = @var{string}
2381 Ignore certain @sc{html} tags when doing a recursive retrieval, just like
2382 @samp{--ignore-tags}.
2384 @item include_directories = @var{string}
2385 Specify a comma-separated list of directories you wish to follow when
2386 downloading---the same as @samp{-I}.
2388 @item inet4_only = on/off
2389 Force connecting to IPv4 addresses, off by default. You can put this
2390 in the global init file to disable Wget's attempts to resolve and
2391 connect to IPv6 hosts. Available only if Wget was compiled with IPv6
2392 support. The same as @samp{--inet4-only} or @samp{-4}.
2394 @item inet6_only = on/off
2395 Force connecting to IPv6 addresses, off by default. Available only if
2396 Wget was compiled with IPv6 support. The same as @samp{--inet6-only}
2399 @item input = @var{string}
2400 Read the @sc{url}s from @var{string}, like @samp{-i}.
2402 @item kill_longer = on/off
2403 Consider data longer than specified in content-length header as invalid
2404 (and retry getting it). The default behavior is to save as much data
2405 as there is, provided there is more than or equal to the value in
2406 @code{Content-Length}.
2408 @item limit_rate = @var{rate}
2409 Limit the download speed to no more than @var{rate} bytes per second.
2410 The same as @samp{--limit-rate}.
2412 @item logfile = @var{string}
2413 Set logfile---the same as @samp{-o}.
2415 @item login = @var{string}
2416 Your user name on the remote machine, for @sc{ftp}. Defaults to
2419 @item mirror = on/off
2420 Turn mirroring on/off. The same as @samp{-m}.
2422 @item netrc = on/off
2423 Turn reading netrc on or off.
2425 @item noclobber = on/off
2428 @item no_parent = on/off
2429 Disallow retrieving outside the directory hierarchy, like
2430 @samp{--no-parent} (@pxref{Directory-Based Limits}).
2432 @item no_proxy = @var{string}
2433 Use @var{string} as the comma-separated list of domains to avoid in
2434 proxy loading, instead of the one specified in environment.
2436 @item output_document = @var{string}
2437 Set the output filename---the same as @samp{-O}.
2439 @item page_requisites = on/off
2440 Download all ancillary documents necessary for a single @sc{html} page to
2441 display properly---the same as @samp{-p}.
2443 @item passive_ftp = on/off/always/never
2444 Change setting of passive @sc{ftp}, equivalent to the
2445 @samp{--passive-ftp} option. Some scripts and @samp{.pm} (Perl
2446 module) files download files using @samp{wget --passive-ftp}. If your
2447 firewall does not allow this, you can set @samp{passive_ftp = never}
2448 to override the command-line.
2450 @item passwd = @var{string}
2451 Set your @sc{ftp} password to @var{password}. Without this setting, the
2452 password defaults to @samp{username@@hostname.domainname}.
2454 @item post_data = @var{string}
2455 Use POST as the method for all HTTP requests and send @var{string} in
2456 the request body. The same as @samp{--post-data}.
2458 @item post_file = @var{file}
2459 Use POST as the method for all HTTP requests and send the contents of
2460 @var{file} in the request body. The same as @samp{--post-file}.
2462 @item progress = @var{string}
2463 Set the type of the progress indicator. Legal types are ``dot'' and
2466 @item protocol_directories = on/off
2467 When set, use the protocol name as a directory component of local file
2468 names. The same as @samp{--protocol-directories}.
2470 @item proxy_user = @var{string}
2471 Set proxy authentication user name to @var{string}, like @samp{--proxy-user}.
2473 @item proxy_passwd = @var{string}
2474 Set proxy authentication password to @var{string}, like @samp{--proxy-passwd}.
2476 @item referer = @var{string}
2477 Set HTTP @samp{Referer:} header just like @samp{--referer}. (Note it
2478 was the folks who wrote the @sc{http} spec who got the spelling of
2479 ``referrer'' wrong.)
2481 @item quiet = on/off
2482 Quiet mode---the same as @samp{-q}.
2484 @item quota = @var{quota}
2485 Specify the download quota, which is useful to put in the global
2486 @file{wgetrc}. When download quota is specified, Wget will stop
2487 retrieving after the download sum has become greater than quota. The
2488 quota can be specified in bytes (default), kbytes @samp{k} appended) or
2489 mbytes (@samp{m} appended). Thus @samp{quota = 5m} will set the quota
2490 to 5 mbytes. Note that the user's startup file overrides system
2493 @item read_timeout = @var{n}
2494 Set the read (and write) timeout---the same as @samp{--read-timeout}.
2496 @item reclevel = @var{n}
2497 Recursion level---the same as @samp{-l}.
2499 @item recursive = on/off
2500 Recursive on/off---the same as @samp{-r}.
2502 @item relative_only = on/off
2503 Follow only relative links---the same as @samp{-L} (@pxref{Relative
2506 @item remove_listing = on/off
2507 If set to on, remove @sc{ftp} listings downloaded by Wget. Setting it
2508 to off is the same as @samp{--no-remove-listing}.
2510 @item restrict_file_names = unix/windows
2511 Restrict the file names generated by Wget from URLs. See
2512 @samp{--restrict-file-names} for a more detailed description.
2514 @item retr_symlinks = on/off
2515 When set to on, retrieve symbolic links as if they were plain files; the
2516 same as @samp{--retr-symlinks}.
2518 @item robots = on/off
2519 Specify whether the norobots convention is respected by Wget, ``on'' by
2520 default. This switch controls both the @file{/robots.txt} and the
2521 @samp{nofollow} aspect of the spec. @xref{Robot Exclusion}, for more
2522 details about this. Be sure you know what you are doing before turning
2525 @item server_response = on/off
2526 Choose whether or not to print the @sc{http} and @sc{ftp} server
2527 responses---the same as @samp{-S}.
2529 @item span_hosts = on/off
2532 @item strict_comments = on/off
2533 Same as @samp{--strict-comments}.
2535 @item timeout = @var{n}
2536 Set timeout value---the same as @samp{-T}.
2538 @item timestamping = on/off
2539 Turn timestamping on/off. The same as @samp{-N} (@pxref{Time-Stamping}).
2541 @item tries = @var{n}
2542 Set number of retries per @sc{url}---the same as @samp{-t}.
2544 @item use_proxy = on/off
2545 Turn proxy support on/off. The same as @samp{-Y}.
2547 @item verbose = on/off
2548 Turn verbose on/off---the same as @samp{-v}/@samp{-nv}.
2550 @item wait = @var{n}
2551 Wait @var{n} seconds between retrievals---the same as @samp{-w}.
2553 @item waitretry = @var{n}
2554 Wait up to @var{n} seconds between retries of failed retrievals
2555 only---the same as @samp{--waitretry}. Note that this is turned on by
2556 default in the global @file{wgetrc}.
2558 @item randomwait = on/off
2559 Turn random between-request wait times on or off. The same as
2560 @samp{--random-wait}.
2564 @section Sample Wgetrc
2565 @cindex sample wgetrc
2567 This is the sample initialization file, as given in the distribution.
2568 It is divided in two section---one for global usage (suitable for global
2569 startup file), and one for local usage (suitable for
2570 @file{$HOME/.wgetrc}). Be careful about the things you change.
2572 Note that almost all the lines are commented out. For a command to have
2573 any effect, you must remove the @samp{#} character at the beginning of
2577 @include sample.wgetrc.munged_for_texi_inclusion
2584 @c man begin EXAMPLES
2585 The examples are divided into three sections loosely based on their
2589 * Simple Usage:: Simple, basic usage of the program.
2590 * Advanced Usage:: Advanced tips.
2591 * Very Advanced Usage:: The hairy stuff.
2595 @section Simple Usage
2599 Say you want to download a @sc{url}. Just type:
2602 wget http://fly.srk.fer.hr/
2606 But what will happen if the connection is slow, and the file is lengthy?
2607 The connection will probably fail before the whole file is retrieved,
2608 more than once. In this case, Wget will try getting the file until it
2609 either gets the whole of it, or exceeds the default number of retries
2610 (this being 20). It is easy to change the number of tries to 45, to
2611 insure that the whole file will arrive safely:
2614 wget --tries=45 http://fly.srk.fer.hr/jpg/flyweb.jpg
2618 Now let's leave Wget to work in the background, and write its progress
2619 to log file @file{log}. It is tiring to type @samp{--tries}, so we
2620 shall use @samp{-t}.
2623 wget -t 45 -o log http://fly.srk.fer.hr/jpg/flyweb.jpg &
2626 The ampersand at the end of the line makes sure that Wget works in the
2627 background. To unlimit the number of retries, use @samp{-t inf}.
2630 The usage of @sc{ftp} is as simple. Wget will take care of login and
2634 wget ftp://gnjilux.srk.fer.hr/welcome.msg
2638 If you specify a directory, Wget will retrieve the directory listing,
2639 parse it and convert it to @sc{html}. Try:
2642 wget ftp://ftp.gnu.org/pub/gnu/
2647 @node Advanced Usage
2648 @section Advanced Usage
2652 You have a file that contains the URLs you want to download? Use the
2659 If you specify @samp{-} as file name, the @sc{url}s will be read from
2663 Create a five levels deep mirror image of the GNU web site, with the
2664 same directory structure the original has, with only one try per
2665 document, saving the log of the activities to @file{gnulog}:
2668 wget -r http://www.gnu.org/ -o gnulog
2672 The same as the above, but convert the links in the @sc{html} files to
2673 point to local files, so you can view the documents off-line:
2676 wget --convert-links -r http://www.gnu.org/ -o gnulog
2680 Retrieve only one @sc{html} page, but make sure that all the elements needed
2681 for the page to be displayed, such as inline images and external style
2682 sheets, are also downloaded. Also make sure the downloaded page
2683 references the downloaded links.
2686 wget -p --convert-links http://www.server.com/dir/page.html
2689 The @sc{html} page will be saved to @file{www.server.com/dir/page.html}, and
2690 the images, stylesheets, etc., somewhere under @file{www.server.com/},
2691 depending on where they were on the remote server.
2694 The same as the above, but without the @file{www.server.com/} directory.
2695 In fact, I don't want to have all those random server directories
2696 anyway---just save @emph{all} those files under a @file{download/}
2697 subdirectory of the current directory.
2700 wget -p --convert-links -nH -nd -Pdownload \
2701 http://www.server.com/dir/page.html
2705 Retrieve the index.html of @samp{www.lycos.com}, showing the original
2709 wget -S http://www.lycos.com/
2713 Save the server headers with the file, perhaps for post-processing.
2716 wget -s http://www.lycos.com/
2721 Retrieve the first two levels of @samp{wuarchive.wustl.edu}, saving them
2725 wget -r -l2 -P/tmp ftp://wuarchive.wustl.edu/
2729 You want to download all the @sc{gif}s from a directory on an @sc{http}
2730 server. You tried @samp{wget http://www.server.com/dir/*.gif}, but that
2731 didn't work because @sc{http} retrieval does not support globbing. In
2735 wget -r -l1 --no-parent -A.gif http://www.server.com/dir/
2738 More verbose, but the effect is the same. @samp{-r -l1} means to
2739 retrieve recursively (@pxref{Recursive Download}), with maximum depth
2740 of 1. @samp{--no-parent} means that references to the parent directory
2741 are ignored (@pxref{Directory-Based Limits}), and @samp{-A.gif} means to
2742 download only the @sc{gif} files. @samp{-A "*.gif"} would have worked
2746 Suppose you were in the middle of downloading, when Wget was
2747 interrupted. Now you do not want to clobber the files already present.
2751 wget -nc -r http://www.gnu.org/
2755 If you want to encode your own username and password to @sc{http} or
2756 @sc{ftp}, use the appropriate @sc{url} syntax (@pxref{URL Format}).
2759 wget ftp://hniksic:mypassword@@unix.server.com/.emacs
2762 Note, however, that this usage is not advisable on multi-user systems
2763 because it reveals your password to anyone who looks at the output of
2766 @cindex redirecting output
2768 You would like the output documents to go to standard output instead of
2772 wget -O - http://jagor.srce.hr/ http://www.srce.hr/
2775 You can also combine the two options and make pipelines to retrieve the
2776 documents from remote hotlists:
2779 wget -O - http://cool.list.com/ | wget --force-html -i -
2783 @node Very Advanced Usage
2784 @section Very Advanced Usage
2789 If you wish Wget to keep a mirror of a page (or @sc{ftp}
2790 subdirectories), use @samp{--mirror} (@samp{-m}), which is the shorthand
2791 for @samp{-r -l inf -N}. You can put Wget in the crontab file asking it
2792 to recheck a site each Sunday:
2796 0 0 * * 0 wget --mirror http://www.gnu.org/ -o /home/me/weeklog
2800 In addition to the above, you want the links to be converted for local
2801 viewing. But, after having read this manual, you know that link
2802 conversion doesn't play well with timestamping, so you also want Wget to
2803 back up the original @sc{html} files before the conversion. Wget invocation
2804 would look like this:
2807 wget --mirror --convert-links --backup-converted \
2808 http://www.gnu.org/ -o /home/me/weeklog
2812 But you've also noticed that local viewing doesn't work all that well
2813 when @sc{html} files are saved under extensions other than @samp{.html},
2814 perhaps because they were served as @file{index.cgi}. So you'd like
2815 Wget to rename all the files served with content-type @samp{text/html}
2816 or @samp{application/xhtml+xml} to @file{@var{name}.html}.
2819 wget --mirror --convert-links --backup-converted \
2820 --html-extension -o /home/me/weeklog \
2824 Or, with less typing:
2827 wget -m -k -K -E http://www.gnu.org/ -o /home/me/weeklog
2836 This chapter contains all the stuff that could not fit anywhere else.
2839 * Proxies:: Support for proxy servers
2840 * Distribution:: Getting the latest version.
2841 * Mailing List:: Wget mailing list for announcements and discussion.
2842 * Reporting Bugs:: How and where to report bugs.
2843 * Portability:: The systems Wget works on.
2844 * Signals:: Signal-handling performed by Wget.
2851 @dfn{Proxies} are special-purpose @sc{http} servers designed to transfer
2852 data from remote servers to local clients. One typical use of proxies
2853 is lightening network load for users behind a slow connection. This is
2854 achieved by channeling all @sc{http} and @sc{ftp} requests through the
2855 proxy which caches the transferred data. When a cached resource is
2856 requested again, proxy will return the data from cache. Another use for
2857 proxies is for companies that separate (for security reasons) their
2858 internal networks from the rest of Internet. In order to obtain
2859 information from the Web, their users connect and retrieve remote data
2860 using an authorized proxy.
2862 Wget supports proxies for both @sc{http} and @sc{ftp} retrievals. The
2863 standard way to specify proxy location, which Wget recognizes, is using
2864 the following environment variables:
2868 This variable should contain the @sc{url} of the proxy for @sc{http}
2872 This variable should contain the @sc{url} of the proxy for @sc{ftp}
2873 connections. It is quite common that @sc{http_proxy} and @sc{ftp_proxy}
2874 are set to the same @sc{url}.
2877 This variable should contain a comma-separated list of domain extensions
2878 proxy should @emph{not} be used for. For instance, if the value of
2879 @code{no_proxy} is @samp{.mit.edu}, proxy will not be used to retrieve
2883 In addition to the environment variables, proxy location and settings
2884 may be specified from within Wget itself.
2888 @itemx --proxy=on/off
2889 @itemx proxy = on/off
2890 This option may be used to turn the proxy support on or off. Proxy
2891 support is on by default, provided that the appropriate environment
2894 @item http_proxy = @var{URL}
2895 @itemx ftp_proxy = @var{URL}
2896 @itemx no_proxy = @var{string}
2897 These startup file variables allow you to override the proxy settings
2898 specified by the environment.
2901 Some proxy servers require authorization to enable you to use them. The
2902 authorization consists of @dfn{username} and @dfn{password}, which must
2903 be sent by Wget. As with @sc{http} authorization, several
2904 authentication schemes exist. For proxy authorization only the
2905 @code{Basic} authentication scheme is currently implemented.
2907 You may specify your username and password either through the proxy
2908 @sc{url} or through the command-line options. Assuming that the
2909 company's proxy is located at @samp{proxy.company.com} at port 8001, a
2910 proxy @sc{url} location containing authorization data might look like
2914 http://hniksic:mypassword@@proxy.company.com:8001/
2917 Alternatively, you may use the @samp{proxy-user} and
2918 @samp{proxy-password} options, and the equivalent @file{.wgetrc}
2919 settings @code{proxy_user} and @code{proxy_passwd} to set the proxy
2920 username and password.
2923 @section Distribution
2924 @cindex latest version
2926 Like all GNU utilities, the latest version of Wget can be found at the
2927 master GNU archive site ftp.gnu.org, and its mirrors. For example,
2928 Wget @value{VERSION} can be found at
2929 @url{ftp://ftp.gnu.org/pub/gnu/wget/wget-@value{VERSION}.tar.gz}
2932 @section Mailing List
2933 @cindex mailing list
2936 There are several Wget-related mailing lists, all hosted by
2937 SunSITE.dk. The general discussion list is at
2938 @email{wget@@sunsite.dk}. It is the preferred place for bug reports
2939 and suggestions, as well as for discussion of development. You are
2940 invited to subscribe.
2942 To subscribe, simply send mail to @email{wget-subscribe@@sunsite.dk}
2943 and follow the instructions. Unsubscribe by mailing to
2944 @email{wget-unsubscribe@@sunsite.dk}. The mailing list is archived at
2945 @url{http://www.mail-archive.com/wget%40sunsite.dk/} and at
2946 @url{http://news.gmane.org/gmane.comp.web.wget.general}.
2948 The second mailing list is at @email{wget-patches@@sunsite.dk}, and is
2949 used to submit patches for review by Wget developers. A ``patch'' is
2950 a textual representation of change to source code, readable by both
2951 humans and programs. The file @file{PATCHES} that comes with Wget
2952 covers the creation and submitting of patches in detail. Please don't
2953 send general suggestions or bug reports to @samp{wget-patches}; use it
2954 only for patch submissions.
2956 To subscribe, simply send mail to @email{wget-subscribe@@sunsite.dk}
2957 and follow the instructions. Unsubscribe by mailing to
2958 @email{wget-unsubscribe@@sunsite.dk}. The mailing list is archived at
2959 @url{http://news.gmane.org/gmane.comp.web.wget.patches}.
2961 Finally, there is a read-only list at @email{wget-cvs@@sunsite.dk}
2962 that tracks commits to the Wget CVS repository. To subscribe to that
2963 list, send mail to @email{wget-cvs-subscribe@@sunsite.dk}. The list
2966 @node Reporting Bugs
2967 @section Reporting Bugs
2969 @cindex reporting bugs
2973 You are welcome to send bug reports about GNU Wget to
2974 @email{bug-wget@@gnu.org}.
2976 Before actually submitting a bug report, please try to follow a few
2981 Please try to ascertain that the behavior you see really is a bug. If
2982 Wget crashes, it's a bug. If Wget does not behave as documented,
2983 it's a bug. If things work strange, but you are not sure about the way
2984 they are supposed to work, it might well be a bug.
2987 Try to repeat the bug in as simple circumstances as possible. E.g. if
2988 Wget crashes while downloading @samp{wget -rl0 -kKE -t5 -Y0
2989 http://yoyodyne.com -o /tmp/log}, you should try to see if the crash is
2990 repeatable, and if will occur with a simpler set of options. You might
2991 even try to start the download at the page where the crash occurred to
2992 see if that page somehow triggered the crash.
2994 Also, while I will probably be interested to know the contents of your
2995 @file{.wgetrc} file, just dumping it into the debug message is probably
2996 a bad idea. Instead, you should first try to see if the bug repeats
2997 with @file{.wgetrc} moved out of the way. Only if it turns out that
2998 @file{.wgetrc} settings affect the bug, mail me the relevant parts of
3002 Please start Wget with @samp{-d} option and send us the resulting
3003 output (or relevant parts thereof). If Wget was compiled without
3004 debug support, recompile it---it is @emph{much} easier to trace bugs
3005 with debug support on.
3007 Note: please make sure to remove any potentially sensitive information
3008 from the debug log before sending it to the bug address. The
3009 @code{-d} won't go out of its way to collect sensitive information,
3010 but the log @emph{will} contain a fairly complete transcript of Wget's
3011 communication with the server, which may include passwords and pieces
3012 of downloaded data. Since the bug address is publically archived, you
3013 may assume that all bug reports are visible to the public.
3016 If Wget has crashed, try to run it in a debugger, e.g. @code{gdb `which
3017 wget` core} and type @code{where} to get the backtrace. This may not
3018 work if the system administrator has disabled core files, but it is
3024 @section Portability
3026 @cindex operating systems
3028 Like all GNU software, Wget works on the GNU system. However, since it
3029 uses GNU Autoconf for building and configuring, and mostly avoids using
3030 ``special'' features of any particular Unix, it should compile (and
3031 work) on all common Unix flavors.
3033 Various Wget versions have been compiled and tested under many kinds
3034 of Unix systems, including GNU/Linux, Solaris, SunOS 4.x, OSF (aka
3035 Digital Unix or Tru64), Ultrix, *BSD, IRIX, AIX, and others. Some of
3036 those systems are no longer in widespread use and may not be able to
3037 support recent versions of Wget. If Wget fails to compile on your
3038 system, we would like to know about it.
3040 Thanks to kind contributors, this version of Wget compiles and works
3041 on 32-bit Microsoft Windows platforms. It has been compiled
3042 successfully using MS Visual C++ 6.0, Watcom, Borland C, and GCC
3043 compilers. Naturally, it is crippled of some features available on
3044 Unix, but it should work as a substitute for people stuck with
3045 Windows. Note that Windows-specific portions of Wget are not
3046 guaranteed to be supported in the future, although this has been the
3047 case in practice for many years now. All questions and problems in
3048 Windows usage should be reported to Wget mailing list at
3049 @email{wget@@sunsite.dk} where the volunteers who maintain the
3050 Windows-related features might look at them.
3054 @cindex signal handling
3057 Since the purpose of Wget is background work, it catches the hangup
3058 signal (@code{SIGHUP}) and ignores it. If the output was on standard
3059 output, it will be redirected to a file named @file{wget-log}.
3060 Otherwise, @code{SIGHUP} is ignored. This is convenient when you wish
3061 to redirect the output of Wget after having started it.
3064 $ wget http://www.gnus.org/dist/gnus.tar.gz &
3067 SIGHUP received, redirecting output to `wget-log'.
3070 Other than that, Wget will not try to interfere with signals in any way.
3071 @kbd{C-c}, @code{kill -TERM} and @code{kill -KILL} should kill it alike.
3076 This chapter contains some references I consider useful.
3079 * Robot Exclusion:: Wget's support for RES.
3080 * Security Considerations:: Security with Wget.
3081 * Contributors:: People who helped.
3084 @node Robot Exclusion
3085 @section Robot Exclusion
3086 @cindex robot exclusion
3088 @cindex server maintenance
3090 It is extremely easy to make Wget wander aimlessly around a web site,
3091 sucking all the available data in progress. @samp{wget -r @var{site}},
3092 and you're set. Great? Not for the server admin.
3094 As long as Wget is only retrieving static pages, and doing it at a
3095 reasonable rate (see the @samp{--wait} option), there's not much of a
3096 problem. The trouble is that Wget can't tell the difference between the
3097 smallest static page and the most demanding CGI. A site I know has a
3098 section handled by a CGI Perl script that converts Info files to @sc{html} on
3099 the fly. The script is slow, but works well enough for human users
3100 viewing an occasional Info file. However, when someone's recursive Wget
3101 download stumbles upon the index page that links to all the Info files
3102 through the script, the system is brought to its knees without providing
3103 anything useful to the user (This task of converting Info files could be
3104 done locally and access to Info documentation for all installed GNU
3105 software on a system is available from the @code{info} command).
3107 To avoid this kind of accident, as well as to preserve privacy for
3108 documents that need to be protected from well-behaved robots, the
3109 concept of @dfn{robot exclusion} was invented. The idea is that
3110 the server administrators and document authors can specify which
3111 portions of the site they wish to protect from robots and those
3112 they will permit access.
3114 The most popular mechanism, and the @i{de facto} standard supported by
3115 all the major robots, is the ``Robots Exclusion Standard'' (RES) written
3116 by Martijn Koster et al. in 1994. It specifies the format of a text
3117 file containing directives that instruct the robots which URL paths to
3118 avoid. To be found by the robots, the specifications must be placed in
3119 @file{/robots.txt} in the server root, which the robots are expected to
3122 Although Wget is not a web robot in the strictest sense of the word, it
3123 can downloads large parts of the site without the user's intervention to
3124 download an individual page. Because of that, Wget honors RES when
3125 downloading recursively. For instance, when you issue:
3128 wget -r http://www.server.com/
3131 First the index of @samp{www.server.com} will be downloaded. If Wget
3132 finds that it wants to download more documents from that server, it will
3133 request @samp{http://www.server.com/robots.txt} and, if found, use it
3134 for further downloads. @file{robots.txt} is loaded only once per each
3137 Until version 1.8, Wget supported the first version of the standard,
3138 written by Martijn Koster in 1994 and available at
3139 @url{http://www.robotstxt.org/wc/norobots.html}. As of version 1.8,
3140 Wget has supported the additional directives specified in the internet
3141 draft @samp{<draft-koster-robots-00.txt>} titled ``A Method for Web
3142 Robots Control''. The draft, which has as far as I know never made to
3143 an @sc{rfc}, is available at
3144 @url{http://www.robotstxt.org/wc/norobots-rfc.txt}.
3146 This manual no longer includes the text of the Robot Exclusion Standard.
3148 The second, less known mechanism, enables the author of an individual
3149 document to specify whether they want the links from the file to be
3150 followed by a robot. This is achieved using the @code{META} tag, like
3154 <meta name="robots" content="nofollow">
3157 This is explained in some detail at
3158 @url{http://www.robotstxt.org/wc/meta-user.html}. Wget supports this
3159 method of robot exclusion in addition to the usual @file{/robots.txt}
3162 If you know what you are doing and really really wish to turn off the
3163 robot exclusion, set the @code{robots} variable to @samp{off} in your
3164 @file{.wgetrc}. You can achieve the same effect from the command line
3165 using the @code{-e} switch, e.g. @samp{wget -e robots=off @var{url}...}.
3167 @node Security Considerations
3168 @section Security Considerations
3171 When using Wget, you must be aware that it sends unencrypted passwords
3172 through the network, which may present a security problem. Here are the
3173 main issues, and some solutions.
3177 The passwords on the command line are visible using @code{ps}. The best
3178 way around it is to use @code{wget -i -} and feed the @sc{url}s to
3179 Wget's standard input, each on a separate line, terminated by @kbd{C-d}.
3180 Another workaround is to use @file{.netrc} to store passwords; however,
3181 storing unencrypted passwords is also considered a security risk.
3184 Using the insecure @dfn{basic} authentication scheme, unencrypted
3185 passwords are transmitted through the network routers and gateways.
3188 The @sc{ftp} passwords are also in no way encrypted. There is no good
3189 solution for this at the moment.
3192 Although the ``normal'' output of Wget tries to hide the passwords,
3193 debugging logs show them, in all forms. This problem is avoided by
3194 being careful when you send debug logs (yes, even when you send them to
3199 @section Contributors
3200 @cindex contributors
3203 GNU Wget was written by Hrvoje Nik@v{s}i@'{c} @email{hniksic@@xemacs.org}.
3206 GNU Wget was written by Hrvoje Niksic @email{hniksic@@xemacs.org}.
3208 However, its development could never have gone as far as it has, were it
3209 not for the help of many people, either with bug reports, feature
3210 proposals, patches, or letters saying ``Thanks!''.
3212 Special thanks goes to the following people (no particular order):
3216 Karsten Thygesen---donated system resources such as the mailing list,
3217 web space, and @sc{ftp} space, along with a lot of time to make these
3221 Shawn McHorse---bug reports and patches.
3224 Kaveh R. Ghazi---on-the-fly @code{ansi2knr}-ization. Lots of
3228 Gordon Matzigkeit---@file{.netrc} support.
3232 Zlatko @v{C}alu@v{s}i@'{c}, Tomislav Vujec and Dra@v{z}en
3233 Ka@v{c}ar---feature suggestions and ``philosophical'' discussions.
3236 Zlatko Calusic, Tomislav Vujec and Drazen Kacar---feature suggestions
3237 and ``philosophical'' discussions.
3241 Darko Budor---initial port to Windows.
3244 Antonio Rosella---help and suggestions, plus the Italian translation.
3248 Tomislav Petrovi@'{c}, Mario Miko@v{c}evi@'{c}---many bug reports and
3252 Tomislav Petrovic, Mario Mikocevic---many bug reports and suggestions.
3257 Fran@,{c}ois Pinard---many thorough bug reports and discussions.
3260 Francois Pinard---many thorough bug reports and discussions.
3264 Karl Eichwalder---lots of help with internationalization and other
3268 Junio Hamano---donated support for Opie and @sc{http} @code{Digest}
3272 The people who provided donations for development, including Brian
3276 The following people have provided patches, bug/build reports, useful
3277 suggestions, beta testing services, fan mail and all the other things
3278 that make maintenance so much fun:
3298 Kristijan @v{C}onka@v{s},
3318 Aleksandar Erkalovi@'{c},
3321 Aleksandar Erkalovic,
3341 Erik Magnus Hulthen,
3360 Goran Kezunovi@'{c},
3371 $\Sigma\acute{\iota}\mu o\varsigma\;
3372 \Xi\varepsilon\nu\iota\tau\acute{\epsilon}\lambda\lambda\eta\varsigma$
3373 (Simos KSenitellis),
3381 Nicol@'{a}s Lichtmeier,
3387 Alexander V. Lukyanov,
3418 @c Texinfo doesn't grok @'{@i}, so we have to use TeX itself.
3420 Juan Jos\'{e} Rodr\'{\i}gues,
3423 Juan Jose Rodrigues,
3437 Szakacsits Szabolcs,
3445 Douglas E. Wegscheid,
3456 Apologies to all who I accidentally left out, and many thanks to all the
3457 subscribers of the Wget mailing list.
3464 @cindex free software
3466 GNU Wget is licensed under the GNU General Public License (GNU GPL),
3467 which makes it @dfn{free software}. Please note that ``free'' in ``free
3468 software'' refers to liberty, not price. As some people like to point
3469 out, it's the ``free'' of ``free speech'', not the ``free'' of ``free
3472 The exact and legally binding distribution terms are spelled out below.
3473 The GPL guarantees that you have the right (freedom) to run and change
3474 GNU Wget and distribute it to others, and even---if you want---charge
3475 money for doing any of those things. With these rights comes the
3476 obligation to distribute the source code along with the software and to
3477 grant your recipients the same rights and impose the same restrictions.
3479 This licensing model is also known as @dfn{open source} because it,
3480 among other things, makes sure that all recipients will receive the
3481 source code along with the program, and be able to improve it. The GNU
3482 project prefers the term ``free software'' for reasons outlined at
3483 @url{http://www.gnu.org/philosophy/free-software-for-freedom.html}.
3485 The exact license terms are defined by this paragraph and the GNU
3486 General Public License it refers to:
3489 GNU Wget is free software; you can redistribute it and/or modify it
3490 under the terms of the GNU General Public License as published by the
3491 Free Software Foundation; either version 2 of the License, or (at your
3492 option) any later version.
3494 GNU Wget is distributed in the hope that it will be useful, but WITHOUT
3495 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
3496 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
3499 A copy of the GNU General Public License is included as part of this
3500 manual; if you did not receive it, write to the Free Software
3501 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
3504 In addition to this, this manual is free in the same sense:
3507 Permission is granted to copy, distribute and/or modify this document
3508 under the terms of the GNU Free Documentation License, Version 1.2 or
3509 any later version published by the Free Software Foundation; with the
3510 Invariant Sections being ``GNU General Public License'' and ``GNU Free
3511 Documentation License'', with no Front-Cover Texts, and with no
3512 Back-Cover Texts. A copy of the license is included in the section
3513 entitled ``GNU Free Documentation License''.
3516 @c #### Maybe we should wrap these licenses in ifinfo? Stallman says
3517 @c that the GFDL needs to be present in the manual, and to me it would
3518 @c suck to include the license for the manual and not the license for
3521 The full texts of the GNU General Public License and of the GNU Free
3522 Documentation License are available below.
3525 * GNU General Public License::
3526 * GNU Free Documentation License::
3529 @node GNU General Public License
3530 @section GNU General Public License
3531 @center Version 2, June 1991
3534 Copyright @copyright{} 1989, 1991 Free Software Foundation, Inc.
3535 675 Mass Ave, Cambridge, MA 02139, USA
3537 Everyone is permitted to copy and distribute verbatim copies
3538 of this license document, but changing it is not allowed.
3541 @unnumberedsec Preamble
3543 The licenses for most software are designed to take away your
3544 freedom to share and change it. By contrast, the GNU General Public
3545 License is intended to guarantee your freedom to share and change free
3546 software---to make sure the software is free for all its users. This
3547 General Public License applies to most of the Free Software
3548 Foundation's software and to any other program whose authors commit to
3549 using it. (Some other Free Software Foundation software is covered by
3550 the GNU Library General Public License instead.) You can apply it to
3553 When we speak of free software, we are referring to freedom, not
3554 price. Our General Public Licenses are designed to make sure that you
3555 have the freedom to distribute copies of free software (and charge for
3556 this service if you wish), that you receive source code or can get it
3557 if you want it, that you can change the software or use pieces of it
3558 in new free programs; and that you know you can do these things.
3560 To protect your rights, we need to make restrictions that forbid
3561 anyone to deny you these rights or to ask you to surrender the rights.
3562 These restrictions translate to certain responsibilities for you if you
3563 distribute copies of the software, or if you modify it.
3565 For example, if you distribute copies of such a program, whether
3566 gratis or for a fee, you must give the recipients all the rights that
3567 you have. You must make sure that they, too, receive or can get the
3568 source code. And you must show them these terms so they know their
3571 We protect your rights with two steps: (1) copyright the software, and
3572 (2) offer you this license which gives you legal permission to copy,
3573 distribute and/or modify the software.
3575 Also, for each author's protection and ours, we want to make certain
3576 that everyone understands that there is no warranty for this free
3577 software. If the software is modified by someone else and passed on, we
3578 want its recipients to know that what they have is not the original, so
3579 that any problems introduced by others will not reflect on the original
3580 authors' reputations.
3582 Finally, any free program is threatened constantly by software
3583 patents. We wish to avoid the danger that redistributors of a free
3584 program will individually obtain patent licenses, in effect making the
3585 program proprietary. To prevent this, we have made it clear that any
3586 patent must be licensed for everyone's free use or not licensed at all.
3588 The precise terms and conditions for copying, distribution and
3589 modification follow.
3592 @unnumberedsec TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
3595 @center TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
3600 This License applies to any program or other work which contains
3601 a notice placed by the copyright holder saying it may be distributed
3602 under the terms of this General Public License. The ``Program'', below,
3603 refers to any such program or work, and a ``work based on the Program''
3604 means either the Program or any derivative work under copyright law:
3605 that is to say, a work containing the Program or a portion of it,
3606 either verbatim or with modifications and/or translated into another
3607 language. (Hereinafter, translation is included without limitation in
3608 the term ``modification''.) Each licensee is addressed as ``you''.
3610 Activities other than copying, distribution and modification are not
3611 covered by this License; they are outside its scope. The act of
3612 running the Program is not restricted, and the output from the Program
3613 is covered only if its contents constitute a work based on the
3614 Program (independent of having been made by running the Program).
3615 Whether that is true depends on what the Program does.
3618 You may copy and distribute verbatim copies of the Program's
3619 source code as you receive it, in any medium, provided that you
3620 conspicuously and appropriately publish on each copy an appropriate
3621 copyright notice and disclaimer of warranty; keep intact all the
3622 notices that refer to this License and to the absence of any warranty;
3623 and give any other recipients of the Program a copy of this License
3624 along with the Program.
3626 You may charge a fee for the physical act of transferring a copy, and
3627 you may at your option offer warranty protection in exchange for a fee.
3630 You may modify your copy or copies of the Program or any portion
3631 of it, thus forming a work based on the Program, and copy and
3632 distribute such modifications or work under the terms of Section 1
3633 above, provided that you also meet all of these conditions:
3637 You must cause the modified files to carry prominent notices
3638 stating that you changed the files and the date of any change.
3641 You must cause any work that you distribute or publish, that in
3642 whole or in part contains or is derived from the Program or any
3643 part thereof, to be licensed as a whole at no charge to all third
3644 parties under the terms of this License.
3647 If the modified program normally reads commands interactively
3648 when run, you must cause it, when started running for such
3649 interactive use in the most ordinary way, to print or display an
3650 announcement including an appropriate copyright notice and a
3651 notice that there is no warranty (or else, saying that you provide
3652 a warranty) and that users may redistribute the program under
3653 these conditions, and telling the user how to view a copy of this
3654 License. (Exception: if the Program itself is interactive but
3655 does not normally print such an announcement, your work based on
3656 the Program is not required to print an announcement.)
3659 These requirements apply to the modified work as a whole. If
3660 identifiable sections of that work are not derived from the Program,
3661 and can be reasonably considered independent and separate works in
3662 themselves, then this License, and its terms, do not apply to those
3663 sections when you distribute them as separate works. But when you
3664 distribute the same sections as part of a whole which is a work based
3665 on the Program, the distribution of the whole must be on the terms of
3666 this License, whose permissions for other licensees extend to the
3667 entire whole, and thus to each and every part regardless of who wrote it.
3669 Thus, it is not the intent of this section to claim rights or contest
3670 your rights to work written entirely by you; rather, the intent is to
3671 exercise the right to control the distribution of derivative or
3672 collective works based on the Program.
3674 In addition, mere aggregation of another work not based on the Program
3675 with the Program (or with a work based on the Program) on a volume of
3676 a storage or distribution medium does not bring the other work under
3677 the scope of this License.
3680 You may copy and distribute the Program (or a work based on it,
3681 under Section 2) in object code or executable form under the terms of
3682 Sections 1 and 2 above provided that you also do one of the following:
3686 Accompany it with the complete corresponding machine-readable
3687 source code, which must be distributed under the terms of Sections
3688 1 and 2 above on a medium customarily used for software interchange; or,
3691 Accompany it with a written offer, valid for at least three
3692 years, to give any third party, for a charge no more than your
3693 cost of physically performing source distribution, a complete
3694 machine-readable copy of the corresponding source code, to be
3695 distributed under the terms of Sections 1 and 2 above on a medium
3696 customarily used for software interchange; or,
3699 Accompany it with the information you received as to the offer
3700 to distribute corresponding source code. (This alternative is
3701 allowed only for noncommercial distribution and only if you
3702 received the program in object code or executable form with such
3703 an offer, in accord with Subsection b above.)
3706 The source code for a work means the preferred form of the work for
3707 making modifications to it. For an executable work, complete source
3708 code means all the source code for all modules it contains, plus any
3709 associated interface definition files, plus the scripts used to
3710 control compilation and installation of the executable. However, as a
3711 special exception, the source code distributed need not include
3712 anything that is normally distributed (in either source or binary
3713 form) with the major components (compiler, kernel, and so on) of the
3714 operating system on which the executable runs, unless that component
3715 itself accompanies the executable.
3717 If distribution of executable or object code is made by offering
3718 access to copy from a designated place, then offering equivalent
3719 access to copy the source code from the same place counts as
3720 distribution of the source code, even though third parties are not
3721 compelled to copy the source along with the object code.
3724 You may not copy, modify, sublicense, or distribute the Program
3725 except as expressly provided under this License. Any attempt
3726 otherwise to copy, modify, sublicense or distribute the Program is
3727 void, and will automatically terminate your rights under this License.
3728 However, parties who have received copies, or rights, from you under
3729 this License will not have their licenses terminated so long as such
3730 parties remain in full compliance.
3733 You are not required to accept this License, since you have not
3734 signed it. However, nothing else grants you permission to modify or
3735 distribute the Program or its derivative works. These actions are
3736 prohibited by law if you do not accept this License. Therefore, by
3737 modifying or distributing the Program (or any work based on the
3738 Program), you indicate your acceptance of this License to do so, and
3739 all its terms and conditions for copying, distributing or modifying
3740 the Program or works based on it.
3743 Each time you redistribute the Program (or any work based on the
3744 Program), the recipient automatically receives a license from the
3745 original licensor to copy, distribute or modify the Program subject to
3746 these terms and conditions. You may not impose any further
3747 restrictions on the recipients' exercise of the rights granted herein.
3748 You are not responsible for enforcing compliance by third parties to
3752 If, as a consequence of a court judgment or allegation of patent
3753 infringement or for any other reason (not limited to patent issues),
3754 conditions are imposed on you (whether by court order, agreement or
3755 otherwise) that contradict the conditions of this License, they do not
3756 excuse you from the conditions of this License. If you cannot
3757 distribute so as to satisfy simultaneously your obligations under this
3758 License and any other pertinent obligations, then as a consequence you
3759 may not distribute the Program at all. For example, if a patent
3760 license would not permit royalty-free redistribution of the Program by
3761 all those who receive copies directly or indirectly through you, then
3762 the only way you could satisfy both it and this License would be to
3763 refrain entirely from distribution of the Program.
3765 If any portion of this section is held invalid or unenforceable under
3766 any particular circumstance, the balance of the section is intended to
3767 apply and the section as a whole is intended to apply in other
3770 It is not the purpose of this section to induce you to infringe any
3771 patents or other property right claims or to contest validity of any
3772 such claims; this section has the sole purpose of protecting the
3773 integrity of the free software distribution system, which is
3774 implemented by public license practices. Many people have made
3775 generous contributions to the wide range of software distributed
3776 through that system in reliance on consistent application of that
3777 system; it is up to the author/donor to decide if he or she is willing
3778 to distribute software through any other system and a licensee cannot
3781 This section is intended to make thoroughly clear what is believed to
3782 be a consequence of the rest of this License.
3785 If the distribution and/or use of the Program is restricted in
3786 certain countries either by patents or by copyrighted interfaces, the
3787 original copyright holder who places the Program under this License
3788 may add an explicit geographical distribution limitation excluding
3789 those countries, so that distribution is permitted only in or among
3790 countries not thus excluded. In such case, this License incorporates
3791 the limitation as if written in the body of this License.
3794 The Free Software Foundation may publish revised and/or new versions
3795 of the General Public License from time to time. Such new versions will
3796 be similar in spirit to the present version, but may differ in detail to
3797 address new problems or concerns.
3799 Each version is given a distinguishing version number. If the Program
3800 specifies a version number of this License which applies to it and ``any
3801 later version'', you have the option of following the terms and conditions
3802 either of that version or of any later version published by the Free
3803 Software Foundation. If the Program does not specify a version number of
3804 this License, you may choose any version ever published by the Free Software
3808 If you wish to incorporate parts of the Program into other free
3809 programs whose distribution conditions are different, write to the author
3810 to ask for permission. For software which is copyrighted by the Free
3811 Software Foundation, write to the Free Software Foundation; we sometimes
3812 make exceptions for this. Our decision will be guided by the two goals
3813 of preserving the free status of all derivatives of our free software and
3814 of promoting the sharing and reuse of software generally.
3817 @heading NO WARRANTY
3825 BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
3826 FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
3827 OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
3828 PROVIDE THE PROGRAM ``AS IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
3829 OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
3830 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
3831 TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
3832 PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
3833 REPAIR OR CORRECTION.
3836 IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
3837 WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
3838 REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
3839 INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
3840 OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
3841 TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
3842 YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
3843 PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
3844 POSSIBILITY OF SUCH DAMAGES.
3848 @heading END OF TERMS AND CONDITIONS
3851 @center END OF TERMS AND CONDITIONS
3855 @unnumberedsec How to Apply These Terms to Your New Programs
3857 If you develop a new program, and you want it to be of the greatest
3858 possible use to the public, the best way to achieve this is to make it
3859 free software which everyone can redistribute and change under these terms.
3861 To do so, attach the following notices to the program. It is safest
3862 to attach them to the start of each source file to most effectively
3863 convey the exclusion of warranty; and each file should have at least
3864 the ``copyright'' line and a pointer to where the full notice is found.
3867 @var{one line to give the program's name and an idea of what it does.}
3868 Copyright (C) 20@var{yy} @var{name of author}
3870 This program is free software; you can redistribute it and/or
3871 modify it under the terms of the GNU General Public License
3872 as published by the Free Software Foundation; either version 2
3873 of the License, or (at your option) any later version.
3875 This program is distributed in the hope that it will be useful,
3876 but WITHOUT ANY WARRANTY; without even the implied warranty of
3877 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
3878 GNU General Public License for more details.
3880 You should have received a copy of the GNU General Public License
3881 along with this program; if not, write to the Free Software
3882 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
3885 Also add information on how to contact you by electronic and paper mail.
3887 If the program is interactive, make it output a short notice like this
3888 when it starts in an interactive mode:
3891 Gnomovision version 69, Copyright (C) 20@var{yy} @var{name of author}
3892 Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
3893 type `show w'. This is free software, and you are welcome
3894 to redistribute it under certain conditions; type `show c'
3898 The hypothetical commands @samp{show w} and @samp{show c} should show
3899 the appropriate parts of the General Public License. Of course, the
3900 commands you use may be called something other than @samp{show w} and
3901 @samp{show c}; they could even be mouse-clicks or menu items---whatever
3904 You should also get your employer (if you work as a programmer) or your
3905 school, if any, to sign a ``copyright disclaimer'' for the program, if
3906 necessary. Here is a sample; alter the names:
3910 Yoyodyne, Inc., hereby disclaims all copyright
3911 interest in the program `Gnomovision'
3912 (which makes passes at compilers) written
3915 @var{signature of Ty Coon}, 1 April 1989
3916 Ty Coon, President of Vice
3920 This General Public License does not permit incorporating your program into
3921 proprietary programs. If your program is a subroutine library, you may
3922 consider it more useful to permit linking proprietary applications with the
3923 library. If this is what you want to do, use the GNU Library General
3924 Public License instead of this License.
3929 @unnumbered Concept Index