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NEWS

changeset 2145: 0c1cfe100028
parent:029380dae568
author: Micah Cowan <micah@cowan.name>
date: Sun Jun 29 19:14:17 2008 -0700 (3 months ago)
permissions: -rw-r--r--
description: Version bump in changelogs.
1GNU Wget NEWS -- history of user-visible changes.
2
3Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
42006, 2007, 2008 Free Software Foundation, Inc.
5See the end for copying conditions.
6
7Please send GNU Wget bug reports to <bug-wget@gnu.org>.
8
9* Changes in Wget 1.11.4
10
11** Fixed an issue (apparently a regression) where -O would refuse to
12download when -nc was given, even though the file didn't exist.
13
14** Fixed a situation where Wget could abort with --continue if the
15remote server gives a content-length of zero when the file exists
16locally with content.
17
18** Fixed a crash on some systems, due to Wget casting a pointer-to-long
19to a pointer-to-time_t.
20
21** Translation updates for Catalan.
22
23* Changes in Wget 1.11.3
24
25** Downgraded -N with -O to a warning, rather than an error.
26
27** Translation updates
28
29* Changes in Wget 1.11.2
30
31** Fixed a problem in authenticating over HTTPS through a proxy.
32(Regression in 1.11 over 1.10.2.)
33
34** The combination of -r or -p with -O, which was disallowed in 1.11,
35has been downgraded to a warning in 1.11.2. (-O and -N, which was never
36meaningful, is still an error.)
37
38** Further improvements to progress bar displays in non-English locales
39(too many spaces could be inserted, causing the display to scroll).
40
41** Successive invocations of Wget on FTP URLS, with --no-remove-listing
42and --continue, was causing Wget to append, rather than replace,
43information in the .listing file, and thereby download the same files
44multiple times. This has been fixed in 1.11.2.
45
46** Wget 1.11 no longer allowed ".." to persist at the beginning of URLs,
47for improved conformance with RFC 3986. However, this behavior presents
48problems for some FTP setups, and so they are now preserved again, for
49FTP URLs only.
50
51* Changes in Wget 1.11.1.
52
53** Interrupted downloads no longer result in renaming the file
54(regression in 1.11 over 1.10.2).
55
56** Progress bar now displays correctly in non-English locales (and a
57related assertion failure was fixed).
58
59** Wget no longer issues a GET request over HTTP for files it should
60know it's not going to download (regression in 1.11 over 1.10.2).
61
62** Added option --auth-no-challenge, to support broken pre-1.11
63authentication-before-server-challenge, which turns out to still be
64useful for some limited cases.
65
66** Documentation of accept/reject lists in the manual's "Types of
67Files" section now explains various aspects of their behavior that may
68be surprising, and notes that they may change in the future.
69
70** Documentation of --no-parents now explains how a trailing slash, or
71lack thereof, in the specified URL, will affect behavior.
72
73* Changes in Wget 1.11.
74
75** Timestamping now uses the value from the most recent HTTP response,
76rather than the first one it got.
77
78** Authentication information is no longer sent as part of the Referer
79header in recursive fetches.
80
81** No authentication credentials are sent until a challenge is issued,
82for improved security. Authentication handling is still not
83RFC-compliant, as once a Basic challenge has been received, it will
84assume it can send credentials to any URL at that same host, and not
85just the ones at or below the original authenticated location.
86Credentials for Digest authentication are still never saved or issued
87automatically, and continue to require a challenge for each resource.
88
89** Added --max-redirect option, allowing the user to specify what should
90be the maximum number of HTTP redirects to follow.
91
92** Wget now supports saving HTTP downloads using file names specified by
93the `Content-Disposition' header. This is a standard way of specifying
94the file name used by many web dynamically generated pages. However, the
95current implementation is inefficient, and known to have bugs. It is
96EXPERIMENTAL only, and not enabled by default. Use --content-disposition
97to enable it.
98
99** The new option `--ignore-case' makes Wget ignore case when
100matching files, directories, and wildcards. This affects the -X, -I,
101-A, and -R options, as well as globbing in FTP URLs.
102
103** ETA projection is now displayed in "dot" progress output as well as
104in the default progress bar. (The dot progress is used by default when
105logging Wget's output to file using the `-o' option.)
106
107** The "lockable boolean" argument type is no longer supported. It
108was only used by the passive_ftp .wgetrc setting. If you're running
109broken scripts or Perl modules that unconditionally specify
110`--passive-ftp' and your firewall disallows it, you can override them
111by replacing wget with a script that execs wget "$@" --no-passive-ftp.
112
113** The source code has been migrated to Mercurial. The repositories are
114available at http://hg.addictivecode.org/. Prior to this, the source
115code was hosted on Subversion (migrated from the original CVS); you can
116still get access to older tags and branches for Wget in the Subversion
117repository at http://addictivecode.org/svn/wget/.
118
119* Changes in Wget 1.10.
120
121** Downloading files larger than 2GB, sometimes referred to as "large
122files", now works on systems that support them. This includes the
123majority of modern Unixes, as well as MS Windows.
124
125** IPv6 is now supported by Wget. Unlike the experimental code in
1261.9, this version supports dual-family systems. The new flags
127`--inet4' and `--inet6' (or `-4' and `-6' for short) force the use of
128IPv4 and IPv6 respectively. Note that IPv6 support has not yet been
129tested on Windows.
130
131** Microsoft's proprietary "NTLM" method of HTTP authentication is now
132supported. This authentication method is undocumented and only used
133by IIS. Note that *proxy* authentication is not supported in this
134release; you can only authenticate to the target web site.
135
136** Wget no longer truncates partially downloaded files when download
137has to start over because the server doesn't support Range. Instead,
138with such servers Wget now simply ignores the data up to the byte
139where the last attempt left off, and only then continues appending to
140the file. That way the downloaded file never shrinks, and download
141retries from servers without support for partial downloads work even
142when downloading to stdout.
143
144** SSL/TLS changes:
145
146*** SSL/TLS downloads now attempt to verify the server's certificate
147against the recognized certificate authorities. This requires CA
148certificates to have been installed in a location visible to the
149OpenSSL library. If this is not the case, you can get the bundle
150yourself from a source you trust (for example, the bundle extracted
151from Mozilla available at http://curl.haxx.se/docs/caextract.html),
152and point Wget to the PEM file using the `--ca-certificate'
153command-line option or the corresponding `.wgetrc' command.
154
155*** Secure downloads now verify that the host name in the URL matches
156the "common name" in the certificate presented by the server.
157
158*** Although the above checks provide more secure downloads, they
159unavoidably break interoperability with some sites that worked with
160previous versions, particularly those using self-signed, expired, or
161otherwise invalid certificates. If you encounter "certificate
162verification" errors or complaints that "common name doesn't match
163requested host name" and are convinced of the site's authenticity, you
164can use `--no-check-certificate' to bypass both checks.
165
166*** Talking to SSL/TLS servers over proxies now actually works.
167Previous versions of Wget erroneously sent GET requests for https
168URLs. Wget 1.10 utilizes the CONNECT method designed for this
169purpose.
170
171*** The SSL/TLS-related options have been redesigned and, for the
172first time, documented in the manual. The old, undocumented, options
173are no longer supported.
174
175** Passive FTP is now the default FTP transfer mode. Use
176`--no-passive-ftp' or specify `passive_ftp = off' in your init file to
177revert to the old behavior.
178
179** The `--header' option can now be used to override generated
180headers. For example, `wget --header="Host: foo.bar"
181http://127.0.0.1' tells Wget to connect to localhost, but to specify
182"foo.bar" in the `Host' header. In previous versions such use of
183`--header' lead to duplicate headers in HTTP requests.
184
185** The responses without headers, aka "HTTP 0.9" responses, are
186detected and handled. Although HTTP 0.9 has long been obsolete, it is
187still occasionally used, sometimes by accident.
188
189** The progress bar is now updated regularly even when the data does
190not arrive from the network.
191
192** Wget no longer preserves permissions of files retrieved by FTP by
193default. Anonymous FTP servers frequently use permissions like "664",
194which might not be what the user wants. The new option
195`--preserve-permissions' and the corresponding `.wgetrc' variable can
196be used to revert to the old behavior.
197
198** The new option `--protocol-directories' instructs Wget to also use
199the protocol name as a directory component of local file names.
200
201** Options that previously unconditionally set or unset various flags
202are now boolean options that can be invoked as either `--OPTION' or
203`--no-OPTION'. Options that required an argument "on" or "off" have
204also been changed this way, but they still accept the old syntax for
205backward compatibility. For example, instead of `--glob=off' you can
206write `--no-glob'.
207
208Allowing `--no-OPTION' for every `--OPTION' and the other way around
209is useful because it allows the user to override non-default behavior
210specified via `.wgetrc'.
211
212** The new option `--keep-session-cookies' causes `--save-cookies' to
213save session cookies (normally only kept in memory) along with the
214permanent ones. This is useful because many sites track important
215information, such as whether the user has authenticated, in session
216cookies. With this option multiple Wget runs are treated as a single
217browser session.
218
219** Wget now supports the --ftp-user and --ftp-password command
220switches to set username and password for FTP, and the --user and
221--password command switches to set username and password for both FTP
222and HTTP. The --http-passwd and --proxy-passwd command switches have
223been renamed to --http-password and --proxy-password respectively, and
224the related http_passwd and proxy_passwd .wgetrc commands to
225http_password and proxy_password respectively. The login and passwd
226.wgetrc commands have been deprecated.
227
228* `wget -b' now works correctly under Windows.
229
230* Wget 1.9.1 is a bugfix release with no user-visible changes.
231
232* Changes in Wget 1.9.
233
234** It is now possible to specify that POST method be used for HTTP
235requests. For example, `wget --post-data="id=foo&data=bar" URL' will
236send a POST request with the specified contents.
237
238** IPv6 support is available, although it's still experimental.
239
240** The `--timeout' option now also affects DNS lookup and establishing
241the TCP connection. Previously it only affected reading and writing
242data. Those three timeouts can be set separately using
243`--dns-timeout', `--connection-timeout', and `--read-timeout',
244respectively.
245
246** Download speed shown by the progress bar is based on the data
247recently read, rather than the average speed of the entire download.
248The ETA projection is still based on the overall average.
249
250** It is now possible to connect to FTP servers through FWTK
251firewalls. Set ftp_proxy to an FTP URL, and Wget will automatically
252log on to the proxy as "username@host".
253
254** The new option `--retry-connrefused' makes Wget retry downloads
255even in the face of refused connections, which are otherwise
256considered a fatal error.
257
258** The new option `--no-dns-cache' may be used to prevent Wget from
259caching DNS lookups.
260
261** Wget no longer escapes characters in local file names based on
262whether they're appropriate in URLs. Escaping can still occur for
263nonprintable characters or for '/', but no longer for frequent
264characters such as space. You can use the new option
265--restrict-file-names to relax or strengthen these rules, which can be
266useful if you dislike the default or if you're downloading to
267non-native partitions.
268
269** Handling of HTML comments has been dumbed down to conform to what
270users expect and other browsers do: instead of being treated as SGML
271declaration, a comment is terminated at the first occurrence of "-->".
272Use `--strict-comments' to revert to the old behavior.
273
274** Wget now correctly handles relative URIs that begin with "//", such
275as "//img.foo.com/foo.jpg".
276
277** Boolean options in `.wgetrc' and on the command line now accept
278values "yes" and "no" along with the traditional "on" and "off".
279
280** It is now possible to specify decimal values for timeouts, waiting
281periods, and download rate. For instance, `--wait=0.5' now works as
282expected, as does `--dns-timeout=0.5' and even `--limit-rate=2.5k'.
283
284* Wget 1.8.2 is a bugfix release with no user-visible changes.
285
286* Wget 1.8.1 is a bugfix release with no user-visible changes.
287
288* Changes in Wget 1.8.
289
290** A new progress indicator is now available and used by default.
291You can choose the progress bar type with `--progress=TYPE'. Two
292types are available, "bar" (the new default), and "dot" (the old
293dotted indicator). You can permanently revert to the old progress
294indicator by putting `progress = dot' in your `.wgetrc'.
295
296** You can limit the download rate of the retrieval using the
297`--limit-rate' option. For example, `wget --limit-rate=15k URL' will
298tell Wget not to download the body of the URL faster than 15 kilobytes
299per second.
300
301** Recursive retrieval and link conversion have been revamped:
302
303*** Wget now traverses links breadth-first. This makes the
304calculation of depth much more reliable than before. Also, recursive
305downloads are faster and consume *significantly* less memory than
306before.
307
308*** Links are converted only when the entire retrieval is complete.
309This is the only safe thing to do, as only then is it known what URLs
310have been downloaded.
311
312*** BASE tags are handled correctly when converting links. Since Wget
313already resolves <base href="..."> when resolving handling URLs, link
314conversion now makes the BASE tags point to an empty string.
315
316*** HTML anchors are now handled correctly. Links to an anchor in the
317same document (<a href="#anchorname">), which used to confuse Wget,
318are now converted correctly.
319
320*** When in page-requisites (-p) mode, no-parent (-np) is ignored when
321retrieving for inline images, stylesheets, and other documents needed
322to display the page.
323
324*** Page-requisites (-p) mode now works with frames. In other words,
325`wget -p URL-THAT-USES-FRAMES' will now download the frame HTML files,
326and all the files that they need to be displayed properly.
327
328** `--base' now works conjunction with `--input-file', providing a
329base for each URL and thereby allowing the URLs in the file to be
330relative.
331
332** If a host has more than one IP address, Wget uses the other
333addresses when accessing the first one fails.
334
335** Host directories now contain port information if the URL is at a
336non-standard port.
337
338** Wget now supports the robots.txt directives specified in
339<http://www.robotstxt.org/wc/norobots-rfc.txt>.
340
341** URL parser has been fixed, especially the infamous overzealous
342quoting. Wget no longer dequotes reserved characters, e.g. `%3F' is
343no longer translated to `?', nor `%2B' to `+'. Unsafe characters
344which are not reserved are still escaped, of course.
345
346** No more than 20 successive redirections are allowed.
347
348* Wget 1.7.1 is a bugfix release with no user-visible changes.
349
350* Changes in Wget 1.7.
351
352** SSL (`https') pages now work if you compile Wget with SSL support;
353use the `--with-ssl' configure flag. You need to have OpenSSL
354installed.
355
356** Cookies are now supported. Wget will accept cookies sent by the
357server and return them in later requests. Additionally, it can load
358and save cookies to disk, in the same format that Netscape uses.
359
360** "Keep-alive" (persistent) HTTP connections are now supported.
361Using keep-alive allows Wget to share one TCP/IP connection for
362many retrievals, making multiple-file downloads faster and less
363stressing for the server and the network.
364
365** Wget now recognizes FTP directory listings generated by NT and VMS
366servers.
367
368** It is now possible to recurse through FTP sites where logging in
369puts you in some directory other than '/'.
370
371** You may now use `~' to mean home directory in `.wgetrc'. For
372example, `load_cookies = ~/.netscape/cookies.txt' works as you would
373expect.
374
375** The HTML parser has been rewritten. The new one works more
376reliably, allows finer-grained control over which tags and attributes
377are detected, and has better support for some features like correctly
378skipping comments and declarations, decoding entities, etc. It is
379also more general.
380
381** <meta name="robots"> tags are now respected.
382
383** Wget's internal tables now use hash tables instead of linked lists
384where appropriate. This results in huge speedups when retrieving
385large sites (thousands of documents).
386
387** Wget now has a man page, automatically generated from the Texinfo
388documentation. (The last version that shipped with a man page was
3891.4.5). To get this, you need to have pod2man from the Perl
390distribution installed on your system.
391
392* Changes in Wget 1.6
393
394** Administrative changes.
395
396*** Maintainership. Due to Hrvoje being plagued with a "real job",
397Dan Harkless is the most active maintainer (not that he doesn't have a
398real job as well). Hrvoje still participates occasionally, and both
399are being helped by many other people.
400
401*** Web page. Thanks to Jan Prikryl, Wget has an "official" web page.
402Take a look at:
403
404 http://sunsite.dk/wget/
405
406*** Anonymous CVS. Thanks to ever-helpful Karsten Thygesen, Wget
407sources are now available at an anonymous CVS server. Take a look at
408the web page for downloading instructions.
409
410** New -K / --backup-converted / backup_converted = on option causes files
411modified due to -k to be saved with a .orig prefix before being changed. When
412using -N as well, it is these .orig files that are compared against the server.
413
414** New --follow-tags / follow_tags = ... option allows you to restrict
415Wget to following only certain HTML tags when doing a recursive
416retrieval. -G / --ignore-tags / ignore_tags = ... is just the
417opposite -- all tags but the ones you specify will be followed.
418
419** New --waitretry / waitretry = SECONDS option allows waiting between retries
420of failed downloads. Wget will use "linear" backoff, waiting 1 second after the
421first failure, 2 after the second, up to SECONDS. waitretry is set to 10 by
422default in the system wgetrc.
423
424** New -p / --page-requisites / page_requisites = on option causes
425Wget to download all ancillary files necessary to display a given HTML
426page properly (e.g. inlined images).
427
428** New -E / --html-extension / html_extension = on option causes Wget
429to append ".html" to text/html filenames not ending in regexp
430"\.[Hh][Tt][Mm][Ll]?".
431
432** New type of .wgetrc command -- "lockable Boolean". Can be set to on, off,
433always, or never. This allows the .wgetrc to override the commandline. So far,
434passive_ftp is the only .wgetrc command which takes a lockable Boolean.
435
436** A number of new translation files have been added.
437
438** New --bind-address / bind_address = <address> option for people on hosts
439bound to multiple IP addresses.
440
441** wget now accepts (illegal per HTTP spec) relative URLs in HTTP redirects.
442
443* Wget 1.5.3 is a bugfix release with no user-visible changes.
444
445* Wget 1.5.2 is a bugfix release with no user-visible changes.
446
447* Wget 1.5.1 is a bugfix release with no user-visible changes.
448
449* Changes in Wget 1.5.0
450
451** Wget speaks many languages!
452
453On systems with gettext(), Wget will output messages in the language
454set by the current locale, if available. At this time we support
455Czech, German, Croatian, Italian, Norwegian and Portuguese.
456
457** Opie (Skey) is now supported with FTP.
458
459** HTTP Digest Access Authentication (RFC2069) is now supported.
460
461** The new `-b' option makes Wget go to background automatically.
462
463** The `-I' and `-X' options now accept wildcard arguments.
464
465** The `-w' option now accepts suffixes `s' for seconds, `m' for
466minutes, `h' for hours, `d' for days and `w' for weeks.
467
468** Upon getting SIGHUP, the whole previous log is now copied to
469`wget-log'.
470
471** Wget now understands proxy settings with explicit usernames and
472passwords, e.g. `http://user:password@proxy.foo.com/'.
473
474** You can use the new `--cut-dirs' option to make Wget create less
475directories.
476
477** The `;type=a' appendix to FTP URLs is now recognized. For
478instance, the following command will retrieve the welcoming message in
479ASCII type transfer:
480
481 wget "ftp://ftp.somewhere.com/welcome.msg;type=a"
482
483** `--help' and `--version' options have been redone to to conform to
484standards set by other GNU utilities.
485
486** Wget should now be compilable under MS Windows environment. MS
487Visual C++ and Watcom C have been used successfully.
488
489** If the file length is known, percentages are displayed during
490download.
491
492** The manual page, now hopelessly out of date, is no longer
493distributed with Wget.
494
495* Wget 1.4.5 is a bugfix release with no user-visible changes.
496
497* Wget 1.4.4 is a bugfix release with no user-visible changes.
498
499* Changes in Wget 1.4.3
500
501** Wget is now a GNU utility.
502
503** Can do passive FTP.
504
505** Reads .netrc.
506
507** Info documentation expanded.
508
509** Compiles on pre-ANSI compilers.
510
511** Global wgetrc now goes to /usr/local/etc (i.e. $sysconfdir).
512
513** Lots of bugfixes.
514
515* Changes in Wget 1.4.2
516
517** New mirror site at ftp://sunsite.auc.dk/pub/infosystems/wget/,
518thanks to Karsten Thygesen.
519
520** Mailing list! Mail to wget-request@sunsite.auc.dk to subscribe.
521
522** New option --delete-after for proxy prefetching.
523
524** New option --retr-symlinks to retrieve symbolic links like plain
525files.
526
527** rmold.pl -- script to remove files deleted on the remote server
528
529** --convert-links should work now.
530
531** Minor bugfixes.
532
533* Changes in Wget 1.4.1
534
535** Minor bugfixes.
536
537** Added -I (the opposite of -X).
538
539** Dot tracing is now customizable; try wget --dot-style=binary
540
541* Changes in Wget 1.4.0
542
543** Wget 1.4.0 [formerly known as Geturl] is an extensive rewrite of
544Geturl. Although many things look suspiciously similar, most of the
545stuff was rewritten, like recursive retrieval, HTTP, FTP and mostly
546everything else. Wget should be now easier to debug, maintain and,
547most importantly, use.
548
549** Recursive HTTP should now work without glitches, even with Location
550changes, server-generated directory listings and other naughty stuff.
551
552** HTTP regetting is supported on servers that support Range
553specification. WWW authorization is supported -- try
554wget http://user:password@hostname/
555
556** FTP support was rewritten and widely enhanced. Globbing should now
557work flawlessly. Symbolic links are created locally. All the
558information the Unix-style ls listing can give is now recognized.
559
560** Recursive FTP is supported, e.g.
561 wget -r ftp://gnjilux.cc.fer.hr/pub/unix/util/
562
563** You can specify "rejected" directories, to which you do not want to
564enter, e.g. with wget -X /pub
565
566** Time-stamping is supported, with both HTTP and FTP. Try wget -N URL.
567
568** A new texinfo reference manual is provided. It can be read with
569Emacs, standalone info, or converted to HTML, dvi or postscript.
570
571** Fixed a long-standing bug, so that Wget now works over SLIP
572connections.
573
574** You can have a system-wide wgetrc (/usr/local/lib/wgetrc by
575default). Settings in $HOME/.wgetrc override the global ones, of
576course :-)
577
578** You can set up quota in .wgetrc to prevent sucking too much
579data. Try `quota = 5M' in .wgetrc (or quota = 100K if you want your
580sysadmin to like you).
581
582** Download rate is printed after retrieval.
583
584** Wget now sends the `Referer' header when retrieving
585recursively.
586
587** With the new --no-parent option Wget can retrieve FTP recursively
588through a proxy server.
589
590** HTML parser, as well as the whole of Wget was rewritten to be much
591faster and less memory-consuming (yes, both).
592
593** Absolute links can be converted to relative links locally. Check
594wget -k.
595
596** Wget catches hangup, filtering the output to a log file and
597resuming work. Try kill -HUP %?wget.
598
599** User-defined headers can be sent. Try
600
601 wget http://fly.cc.her.hr/ --header='Accept-Charset: iso-8859-2'
602
603** Acceptance/Rejection lists may contain wildcards.
604
605** Wget can display HTTP headers and/or FTP server response with the
606new `-S' option. It can save the original HTTP headers with `-s'.
607
608** socks library is now supported (thanks to Antonio Rosella
609<Antonio.Rosella@agip.it>). Configure with --with-socks.
610
611** There is a nicer display of REST-ed output.
612
613** Many new options (like -x to force directory hierarchy, or -m to
614turn on mirroring options).
615
616** Wget is now distributed under GNU General Public License (GPL).
617
618** Lots of small features I can't remember. :-)
619
620** A host of bugfixes.
621
622* Changes in Geturl 1.3
623
624** Added FTP globbing support (ftp://fly.cc.fer.hr/*)
625
626** Added support for no_proxy
627
628** Added support for ftp://user:password@host/
629
630** Added support for %xx in URL syntax
631
632** More natural command-line options
633
634** Added -e switch to execute .geturlrc commands from the command-line
635
636** Added support for robots.txt
637
638** Fixed some minor bugs
639
640* Geturl 1.2 is a bugfix release with no user-visible changes.
641
642* Changes in Geturl 1.1
643
644** REST supported in FTP
645
646** Proxy servers supported
647
648** GNU getopt used, which enables command-line arguments to be ordered
649as you wish, e.g. geturl http://fly.cc.fer.hr/ -vo log is the same as
650geturl -vo log http://fly.cc.fer.hr/
651
652** Netscape-compatible URL syntax for HTTP supported: host[:port]/dir/file
653
654** NcFTP-compatible colon URL syntax for FTP supported: host:/dir/file
655
656** <base href="xxx"> supported
657
658** autoconf supported
659
660----------------------------------------------------------------------
661Copyright information:
662
663Copyright (C) 1997-2005 Free Software Foundation, Inc.
664
665 Permission is granted to anyone to make or distribute verbatim
666 copies of this document as received, in any medium, provided that
667 the copyright notice and this permission notice are preserved, thus
668 giving the recipient permission to redistribute in turn.
669
670 Permission is granted to distribute modified versions of this
671 document, or of portions of it, under the above conditions,
672 provided also that they carry prominent notices stating who last
673 changed them.