GNU Website Guidelines

Our goal is to get information to people. Keeping the site design simple helps accomplish that.

Please be considerate of all who access our web pages, and accommodate them, including those who use text-only browsers or old browsers, as well as those with slow connections. We wish to prevent web designs that look great under one version of one browser, and ugly under many others. Of course, please don't install any of the proprietary web browsers available if you don't already use them anyway.

General Guidelines

• The GNU web server has only free software available. We prefer that only free software be used to prepare pages for the GNU web server.
• The GNU website lists and links only to free software. The software's source code and executables have to be freely redistributable and modifiable to and by all people and organizations. If in doubt, ask <gnu@gnu.org>.
• The GNU website gives priority to software covered by either the GNU General Public License or GNU Lesser General Public License.
• The use of graphics should be minimized so pages load fast over slow links.
• Offer a document in as many formats as the GNU Project has it. For an example, see The GNU Free Documentation License. This lets users get the document in the format most useful to them.
• In addition to copyright and license notices, all pages should have contact info for both the FSF (or responsible party) and the address for bug reports (webmasters for general pages, but project-specific addresses otherwise) at the bottom of each page. The reason to note this at the bottom is so the user always finds this information at the same place on each page.
• Before you take any graphics or text from another website, please ask for permission to use it. It's polite to do so. It is also essential for us to avoid copyright infringement.
• Before adding a link, check that it follows our linking criteria.
• Do not list an address of an individual, including the maintainer of a GNU package, unless explicitly asked to have it listed. Most GNU maintainers do not want a lot of extra mail and prefer to get bug reports, etc. from the GNU bug report mailing lists.
• On pages with dated entries (e.g., /philosophy/latest-articles.html), the newer entries should be first (i.e., reverse chronological order).
• Pages should not load CSS from servers other than those run by the FSF.
• Generally, the use of JavaScript is not allowed. Exceptions to this need to be reviewed and approved by the Chief GNUisance on a case-by-case basis.

Copyright Guidelines

• Every page should have a copyright notice. See the boilerplate, referred below.
• Every page should have a notice giving everyone permission to distribute it. If you cannot get such a permission from the author, please discuss the issue with the webmasters before posting it. This applies to CSS as well as to HTML.
• Normally you shouldn't post a page that isn't copyright FSF unless we have permission to modify the version we publish. If you cannot get such a permission from the author, please discuss the issue with the FSF before posting it. This applies to CSS as well as to HTML.
• If ultimately we decide to post a new page we don't have permission to modify, put the text “Posted in 20XX without FSF permission to modify” inside an HTML comment, just after the copyright notice.
• The user of our pages should always find the copyright information at the same place on each page. If the page is copyrighted by some other person or entity, use per or its copyright notice instead of the FSF copyright notice. Use the rest of the FSF's normal footer material, except when there is a specific reason to change something in it.
• All pages that explain how to do something, such as how to use certain programs, are documentation. This includes all the pages in /software/ that describe specific programs. By our principles, documentation must be free. So these pages must carry a free license. If such a page doesn't have a free license, please report the problem to <webmasters@gnu.org>.
• For other pages, use the same license as some other page that serves a similar kind of purpose.

Spelling and Punctuation

• English pages should follow the standard American spelling, hyphenation and punctuation conventions.
• Since these conventions are not always very specific, especially as regards hyphenation and quotes, gnu.org adds its own rules for the sake of consistency:
  • The term “nonfree” is preferred over “non-free”; likewise, “noncommercial” over “non-commercial.”
  • In ordinary text, HTML entities ““…”” and “‘…’” are preferred over straight quotes ("..." and '...'). This doesn't apply to script-generated documents.
  • Where they exist, the double spaces after sentence breaks should be preserved. They enable Emacs sentence commands to do the right thing.

Filenames

• To make simultaneous edition of many files easier, try and give each HTML file a unique and descriptive name; the special filename index.html should only be used as a symbolic link, as explained next.
• Each directory in the web server tree should have a symbolic link named index.html to the top-level HTML file for that directory. Use the .symlinks file to handle this.
• If you translate your web page in different languages, please name the English file article.html, and its translations article.lang.html— lang should contain the two-letter language code from ISO 639, and optionally an hyphen followed the two-letter country code given in ISO 3166 (lowercase). For example, the German translation of not-ipr.html should be named not-ipr.de.html; the Brazilian Portuguese translation should be named not-ipr.pt-br.html.

URLs

• Hand-written URLs that refer to other files on www.gnu.org should be absolute, starting from the root page. That is, paths should start with / (e.g., /gnu/about-gnu.html; not http://www.gnu.org/gnu/about-gnu.html, and not about-gnu.html). This makes it easier to copy and paste links from other pages. Besides, links like http://www.gnu.org/ will be wrong when the visitor uses HTTPS.
• Check if the linked host supports both HTTPS and HTTP and use protocol-relative URLs (e.g. //www.example.org) if it does.
• Collections of files produced automatically from Texinfo source contain links with relative file names. They always refer to another file in the same directory. These relative links are to be tolerated.
• Don't use just a directory name in a URL; always include the specific filename. E.g., use /gnu/gnu.html, not just /gnu/. Never use index.html in a URL. Both of these are kindnesses to the user, as browsers change the highlighting on a link after it has been visited. If links to a given file use several different URLs, the URLs that haven't been explicitly referenced will not be highlighted as visited. So the user goes to pages he/she has already seen, which is irritating. Also, this eases maintenance of the site as things get moved around.
• Be sure to omit the filename entirely when linking to an anchor in the same file and double-check that the anchor actually works.
• Consider others linking to your page when removing an anchor or id attribute.
• We encourage FTP sites to use a directory for each package, and only put one package's files in each directory, so that the users can see what versions of that package and related information can be downloaded (e.g., a README file, information of what versions are available, documentations, fonts, etc.). Also, it means that the FTP location URLs do not need to be changed, on this and other sites, as new versions are released into that directory.

• Cite people with e-mail addresses this way:

  <a href="//www.stallman.org/">Richard Stallman</a> <a href="mailto:rms@gnu.org">&lt;rms@gnu.org&gt;</a>

  which browsers display this way:

  Richard Stallman <rms@gnu.org>

  It is less confusing to the user, because it's clear what is a link to another web page and what is a mailto: anchor that will bring up a mail form to fill out and send, if this is supported by the client. Also, if users save a copy of the page, they will have a copy of the e-mail address they can use without going back to their web browser. If the person doesn't have a web page, leave the name unanchored.

• When embedding static resources like videos that are not in the www CVS repository along with the rest of the www.gnu.org pages, it's important that the URL used to embed the asset be a subdomain of gnu.org, so that the Third-party Request Blocker add-on shipped with GNU IceCat would not consider it a third-party asset which it would prevent from being loaded. For example, when embedding videos from FSF campaigns on www.gnu.org, use static.gnu.org rather than static.fsf.org. Both of these addresses have been set to point to the same machine, so they can be used interchangeably.

HTML Guidelines

• HTML on the GNU web server should be strictly compliant with W3C standards.
• Please follow the above mentioned web standards strictly. Don't neglect required elements such as <html>, <head>, <title>, <body>, etc. when using (X)HTML, and always include the appropriate DTD or Schema reference. This appeases overly pedantic web browsers.
• Do not add comments at the top of a document. Web browsers expect the doctype, XML declaration, or Schema to be at the top. Comments will confuse them, and often cause them to incorrectly interpret your markup.
• The <head> element should contain this line:

  <link rel="author" href="mailto:webmasters@gnu.org">

  Some browsers use this information to allow users to easily report problems they find on a page.
• The first header tag, <h[n]>, should have its text duplicated at the start of the <title> tag. The <title> tag is used by many browsers in menus like the history and bookmarks lists, as a link to that page. Repeating the main heading in the <title> ensures that, when users click on an item in these menus, they get a page with the expected heading. Please properly use your headers in numerical order: 1, 2, etc. These are not used for looks, but for the organization of the document.
• The <title> tag should include the phrases “GNU Project” and “Free Software Foundation” so the pages will be found when web search engines are used. The default is to add this at the end: - GNU Project - Free Software Foundation.
• Acronyms/abbreviations:
  • Never use <acronym>: HTML 5 obsoletes it in favor of <abbr>.
  • Don't use <abbr> unless for a really compelling reason. Browsers render it in an ugly way.
  • When an abbreviation may be unfamiliar to a reader, give its expansion the first time it is used in a document, like this: <abbr title="Expanded Abbreviation">EA</abbr> or EA (Expanded Abbreviation).
  • Further occurrences, in any case, should be written without any markup: just EA.
  • For common-enough initialisms, such as GNU, FSF, BSD, RAM, HTML, DVD, and so on and so on, no markup is needed at all. Use your judgment.

Tables and menus

• Please use tables to organize data, not the presentation of the web page.
• Screen reader software used by most blind people reads the text from left to right, ignoring any tables that you make. If you use tables, you should make sure that reading a whole page left to right doesn't confuse such software. Please follow the W3C web accessibility guidelines to ensure that tables are properly marked for accessibility.
• Some people like to organize links as a menu to the left or right of the main text when using graphical browsers. That does not work very well with text browsers since they will make the menu appear either on top of the page or at the bottom. If you have a menu that is more than 30 lines long, then it's very probable that a user viewing the page will never bother to read the text because it will be too far down. You should make an effort to keep such menus under 20 lines long so that the beginning of the article is visible on the first page when viewing it with a text browser. A menu bar of one or two horizontal lines might accomplish your purpose as well. Providing a “skip link” to the main text is another option.

Using our page template

• To help people follow the above guidelines, a page template (or “boilerplate”) is provided for both the main part of the GNU website, and the software projects. Its use is mandatory for new pages in www.gnu.org, and highly recommended for software pages. Please don't start out with an existing page to create a new one; use the original source of the boilerplate instead, and follow the instructions in it.
• The XHTML templated pages must follow the XHTML-1.0 guidelines.
• Our server-side includes declare UTF-8 as the character encoding, so using any other encoding is problematic.

Styling

Styling of templated pages

• Generic styling for desktops and smartphones is provided by /layout.css; it covers most of our use cases.
• Printers use /print.css. Note that the header, navigation bars and footer (except copyright and license) are unprintable.
• In addition to /layout.css, some pages have specialized stylesheets: /graphics/graphics.css for the GNU Art section, and /side-menu.css for the Malware and Education sections.
• If some special styling is needed for a specific page, it should be added to the page itself in a <style> element, between the SSI directives that include header.html and banner.html. If the style applies to a single element, it should normally be added as an attribute.
• If you specify any color attribute in the HTML, you should specify all of them that are allowed for that tag. This is because some browsers allow users to specify defaults for the color attributes, and the user's choices could conflict with your choices, as your choices override the user's choices. In the worse case, the foreground and background could end up the same. Please use a stylesheet for this, and not HTML 3.2 (HTML 4 Transitional) deprecated markup.

Other stylesheets

• Historical pages (unmaintained translations for the most part) refer to /gnu.css, which in turn loads /mini.css (the Yahoo User Interface reset and base stylesheet, version 2), as these pages are usually very basic, plain pages with little or no formatting.
• There are dedicated stylesheets for software manuals. The main ones are:
  • /style.css;
  • gnulib.css, which imports /style.css and adds a few more definitions; it is used by gendocs.sh to regenerate Texinfo manuals.
• Translators maintain stylesheets (/style.lang.css) that modify layout.css according to their own needs. The RTL languages (Arabic, Persian, and Hebrew) use /style.rtl.css.

Use of Graphics

• The use of graphics should be minimized, so pages load fast over slow links, especially animations.
• We do not use background images on our pages, as they make text significantly harder to read.
• In the past, GIFs have had patent problems. However, now that the IBM and Unisys patents (and other patents worldwide that are relevant to LZW compression) have expired, GIFs that are based on the 87a or 89a standard are acceptable. Please be wary of proprietary applications that may include non-standard patented technologies (we'd prefer you use free software applications when authoring for our websites). In general, PNG or JPEG format are still safe, and are probably better from a technical standpoint. For details regarding the old GIF problem, see https://www.gnu.org/philosophy/gif.html. Other formats are also allowed, though JPEG is the one most widely recognized by web browsers (avoid JPEG 2000, and be careful with PNG alpha channels; the former is not widely supported, and the latter are not fully supported by some older browsers).
• Before you take an image from another website, please ask for permission to use it.
• Always have a textual alternative for in-line images, to ensure indexability by search engines and accessibility. For instance:

  <img src="/graphics/*.jpg" alt="&nbsp;[DESCRIPTIVE TEXT]&nbsp;">

  We add the non-breaking spaces (&nbsp;) and square brackets to separate the DESCRIPTIVE TEXT from adjacent text, and help the user realize that this is a stand-in for an image. The point of using non-breaking spaces rather than normal ones is to make sure they find their way to the translatable strings that are extracted by the PO4A/Gettext tools.
• Make sure the image doesn't look too big or too small when displayed at its original size, using the browser's default font size.

• Adjust image width or height in a style attribute, using scalable units such as em or %; for instance:

  <img src="/graphics/*.jpg" alt="&nbsp;[DESCRIPTIVE TEXT]&nbsp;" style="width: 10em; height: auto;" />

  This way, the page will look the same if the reader increases or decreases font size.

• If you are adding a small floating image to a page that uses layout.css (the stylesheet for templated pages), you may want to use the imgright or imgleft class (defined in the IMAGES section of the stylesheet). This will ensure that the floating direction is reversed if the page is translated into an RTL language.
• If the image you are adding is 12em wide or more, and the page is templated, you may find it convenient to use one of the responsive pict classes that are defined in the IMAGES section of layout.css (you can adjust the width in a style attribute if none of the predefined ones fits your needs); for instance:

  <div class="pict wide" style="width: 25em"><img src="/graphics/*.jpg" alt="&nbsp;[DESCRIPTIVE TEXT]&nbsp;" /></div>

  Note that the div container is necessary because some browsers (e.g., NetSurf) don't know how to apply max-width to images.

• Link all images that are displayed throughout the website to the relevant page, usually in /graphics/. This can be done with code similar to this, which corresponds to the image on the left:

  

  <p class="imgleft">
  <a href="/graphics/agnuhead.html">
  <img src="/graphics/gnu-head-sm.jpg"
       alt=" [Image of the Head of a GNU] "
       style="width: 8em" /></a>
  </p>
  

  This will allow users to quickly go to pages related to the pictures they are interested in.

Appendix 1 - Linking Policies

One of the most complex aspects of maintaining web pages is following the linking guidelines; however, it's also a very crucial aspect of the job.

We strive to ensure that all pages we promote—all pages which are given links on our site—are friendly to the free software movement. Some pages will obviously not meet such standards; if the site flames the Free Software Foundation and/or the GNU Project, or has no apparent relation to free software and surrounding issues, the link shouldn't be made. Beyond that, however, there are criteria used in determining whether or not it is appropriate to provide a link to a page from ours. They are listed below, in order of descending general importance.

What's the context of the link?

The link's purpose on our site will play a role in determining how strongly it should be judged against the other criteria. Pages hosting GNU projects will be held to the highest standards. Pages about other free software and given high promotion—for example, included in a newsfeed on the main page—are a close second. Links on the philosophy page may be given more leeway in talking about proprietary software; GNU/Linux user group pages should call the system GNU/Linux almost always but are hardly checked on other criteria. Always keep this in mind when deciding how to weigh each aspect of these policies.

Does the page promote proprietary software?

The big point made by the free software movement is that proprietary software presents an ethical dilemma: you cannot agree to such nonfree terms and treat those around you as you would like to be treated. When proprietary software is promoted, people get the impression that it is okay to use it, while we are trying to convince them otherwise. As such, we avoid offering such free advertising, either directly on our site or indirectly through links.

What's tricky about this criteria is the “promotion” point: there's a difference between mentioning proprietary software and making a sales pitch for it. Indeed, the GNU Project website mentions proprietary software throughout, but never gives people the impression that its use does not present ethical problems.

There are two things to keep in mind when determining whether a reference to proprietary software promotes it, or simply mentions it. First, how much information does it offer about the software? Second, how much information is the reader likely to actually gain from this page?

Different pages provide different amounts of information about proprietary software; the more it provides, the more of a problem it poses for us. For example, some pages may link to the primary site for a proprietary software program. Others may describe its functionality in detail. Even the product name given matters; there's a difference between “Windows” and “Microsoft Windows XP Home Edition.”

The subject of the reference will also play a role in determining how problematic a reference is. If the software is already very popular, it's unlikely that a basic mention of it will be news to the reader. Some examples of proprietary software which are common enough to be considered “well-known” are major operating systems (Windows, Mac OS, Sun OS, HP-UX) and primary common applications such as Office, Internet Explorer, Chrome, Photoshop, Acrobat Reader, and Flash.

GNU software project pages feel the full force of this policy. Proprietary software should only be mentioned when the GNU software provides support for it, or to compare it against the features of well-known proprietary software. For example, the following text—and not much else—would be acceptable:

w3 is a web browser for GNU Emacs, similar to Internet Explorer. It can run on all platforms GNU Emacs runs on, including GNU/Linux, proprietary Unix systems, and Windows.

Links which appear in other areas, such as the testimonials or philosophy pages, as well as links to user groups or third party organizations, may discuss such software in greater detail, but links and other methods of encouragement to “learn more” should still be avoided.

How does the page compare free software to open source?

Almost all pages which have links on our site should, at the very least, treat free software and open source equally. Failure to do so—whether it be by omitting free software or by implying that open source is superior—is usually unacceptable. GNU software project pages should have little mention of open source. Here's an example of a tactful way to do it:

XYZ is part of the GNU Project, and is free/libre software (sometimes referred to as open source software).

Any exceptions to this rule should be apparent from the context. For instance, user group pages or pages of organizations listed in links.html may talk in greater detail about open source; we state on those pages, “The FSF is not responsible for the contents of other websites, or how up-to-date their information is.”

How does the page treat the GNU Project?

Pages which we link to should treat the GNU Project well. The primary thing to look out for in this regard is whether the page calls the system GNU/Linux or just “Linux.” GNU software projects and user group pages should almost never, if ever, fail to do this. Again, exceptions for other pages should be apparent from context.

That said, certain parts of a page should not be considered against these criteria. For example, suppose we were to make a link to a page on a free software news site. Any advertisements or reader comments attached to the article would not be considered when determining whether it met our linking guidelines, since they're understood to be the opinion of their individual authors. Similarly, on user group or third party organization pages, the contents of forums and wiki pages should not hold weight in these regards.

Finally, some sites are understood to always have exception with most of these guidelines. These sites are usually about issues which are important, but somewhat peripheral, to the free software movement. Several times we have linked to the Electronic Frontier Foundation's site, even though they encouraged the use of Flash, talked exclusively about open source software, and do not advocate users' freedom to redistribute and change software. It's generally understood that since these pages are not primarily about free software, the policies do not hold full force for them.

As a final explanation (coming from RMS): Even for making links from www.gnu.org, we do not require that people call the system GNU/Linux or use the term “free software” rather than “open source.” We do, however, require that they not promote any nonfree software.

If all this seems complicated, that's because, unfortunately, it is. Don't worry; a knack for it comes with time and experience. You may mis-evaluate a few pages as you're learning to get a feel for what's acceptable and what isn't; please don't hesitate to get a second opinion from a more experienced webmaster, or someone in charge like the Chief Webmaster or RMS. New exceptions will always come up; keep an open mind to that possibility and be ready to handle them properly.

Does the page work even if the user's browser refuses to run JavaScript code?

If the page requires nonfree, nontrivial JavaScript and has serious failures with JavaScript disabled, the link shouldn't be made. Similarly, if the page has embedded Flash that plays an important role, so that a person would be missing something important if the videos do not play, the link should not be made.

In some cases, however, we can still refer to such pages and resources by using workarounds to bypass the JavaScript requirement.

One possibility is to use an instance of GotHub—a free software frontend for GitHub that works without JavaScript—to replace links to pages and resources hosted at GitHub, a website that requires running nonfree JavaScript to be usable as intended.

Currently (March 2024), GotHub is not actively maintained and it lacks some functionalities. For example, it doesn't offer a way to browse repositories or download the source code without visiting the GitHub website, and it doesn't provide a git clone URL. Still, GotHub is helpful for some usages. For example, it works well for linking to individual files.

* Software packages. A useful file for software projects is the README file; it contains a description of the package, which is usually the first thing a user wants to see before attempting to fetch the repository. We have applied this solution several times in www.gnu.org; for example, we replaced this:
https://github.com/pbatard/rufus
with this:
https://gothub.projectsegfau.lt/pbatard/rufus.

Another solution is to link directly to the tarball of a tagged commit on GitHub. The drawback of this method is that it is not very useful for tracking the project over time.

* Graphics, documents, manuals. These resources are sometimes hosted in user pages that do not require JavaScript to be fully usable, even when they are hosted inside an area of the GitHub website. In these cases, it is okay to link to such pages. For example, we replaced a link to
https://github.com/foocorp/gnu-fm/blob/main/clients/meego/librefm/src/librefm-logo.png
with a link to
https://raw.githubusercontent.com/foocorp/gnu-fm/main/clients/meego/librefm/src/librefm-logo.png .
And we have links to documents such as
https://raw.githubusercontent.com/scootergrisen/licenser/master/gpl-3.0.da.txt.

Sometimes a resource may be hosted in more than one acceptable place. It can be a personal page in GitHub or somewhere else, or in some unrelated website. When evaluating which one to choose, consider factors such as: What's the status of the document? Is it a final version or is it likely to be modified anytime soon? Is the URL reliably stable, or is it likely to be moved?

For example, in the past we had the case of a manual that was listed in other-free-books.html with this URL:
https://github.com/davidam/orgguide-es.
At the time, we had three possibilitites to replace that bad link:
1. GotHub
https://gothub.projectsegfau.lt/raw/davidam/davidam.github.io/master/docu/orgguide.es.pdf
2. Author's personal space at GitHub
https://raw.githubusercontent.com/davidam/davidam.github.io/master/docu/orgguide.es.pdf
3. Publisher/Bookstore
https://traficantes.net/sites/default/files/pdfs/orgguide.es_.pdf
We decided for the third one, since it didn't seem that the manual was likely to be updated to a new version, and Traficantes de Sueños is an established, well-known publisher.

Issue trackers on GitHub can be viewed and browsed without JavaScript, but active participation entails an account that can't be created without running nonfree JavaScript. It's okay to link to closed issues, like we did for
https://github.com/w3c/fingerprinting-guidance/issues/8.
Another possibility for closed issues is to link to the archived page at the Wayback Machine.

Lastly, consider the possibility of talking to maintainers and authors to explain the problem. Hopefully they will move the repo somewhere else or post the material in a place we can link to.

Appendix 2 - Working with Web CVS Repositories

Basic CVS commands

• For reference manual, execute info cvs.
• Before the initial checkout, set the environment variable CVS_RSH=ssh.

• If you have write access to www, check out the main www repository with your Savannah login:

  cvs -z3 -d:ext:username@cvs.savannah.gnu.org:/web/www co www
  

  You will get a working directory, www, with the same structure as our main website.

• If you don't have write access to www, you can still make an anonymous checkout of www:

  cvs -z3 -d:pserver:anonymous@cvs.savannah.gnu.org:/web/www co www
  

• Check out the web repository of the fooproject:

  cvs -z3 -d:ext:username@cvs.savannah.gnu.org:/web/fooproject \
           co fooproject
  

  You will get a working directory, fooproject, with the same structure as the www/software/fooproject subdirectory. Note, however, that the fooproject and www repositories are independent. The working directories can be anywhere in your filesystem.

  Webmasters, please read Web pages for official GNU software before committing anything to the web repository of a software project.

• Add a file or directory:

  cvs add foo
  

• Update before you edit a file:

  cvs update -P foo
  

• Check the changes you are going to commit:

  cvs diff -U2 foo
  

• Perform the commit (no need for cvs add if the file is already in the repository):

  cvs commit foo
  

  This will open a text editor where you should enter a log message. It will also show you a list of all files to be committed. The commit will occur upon exiting the editor.

  Alternatively:

  cvs commit -m "Log message" foo
  

  This option is somewhat less safe, as it doesn't show you a list of the files to be committed. Moreover, a minor typo in the log message (omitting the space between the message and the filename) may result in committing all modified files in a directory, because the filename will not be treated as an argument, but as part of the message.

  It's important to write good commit log messages to help project members and future generations find specific changes in a given file and understand why your changes were made.

  • Without being excessively verbose, log messages should describe as clearly as possible the nature of the commit.
    Good: Update link to XYZ.
    Bad: Update a link.
  • Always include a reference to any related RT tickets and/or mailing lists discussions. If no such reference exists, mention the name of the person(s) who authorized the change.
  • For dates, we use either the American-style notation (Sept. 27, 2023) or the ISO 8601 international standard format (2023-09-27).

  Whenever possible, changes to multiple files that share the same log message should be bundled in one commit. Do not bundle multiple unrelated changes in one commit.

  The changes (except to .symlinks files) should be visible on www.gnu.org within minutes.

For further details on CVS, such as reverting to a previous version, or looking at the diff output of a particular change, see the CVS documentation.

Symbolic links

Since CVS is not able to handle symbolic links directly, a separate mechanism has been implemented to allow webmasters to maintain symbolic links, as follows. (Actual symbolic links are no longer created on www.gnu.org; mod_rewrite rules are used instead. But we'll keep this discussion talking about symlinks since it is easier to understand that way.)

Being a symlink means that relative links from the linked page may break when the symlink jumps to a different directory.

Special files, named .symlinks, when committed to the CVS tree, are interpreted as specifications to build symbolic links. Each symbolic link specification from the .symlinks file is honored, i.e., the symbolic link is created if it does not exist yet. If a symbolic link is found in the directory and is not listed in the .symlinks file, it is removed.

The .symlinks files obey the ln -s format, as described below:

• Lines starting with a sharp sign (“#”) are ignored.
• Lines that do not contain two strings separated by white space are silently ignored.

Here is an example of a .symlinks file:

# Make a link named l.html to a target t.html.
# Strictly equivalent to ln -s t.html l.html:
t.html l.html

On each line the first file name must be a relative path name to an existing file. The second file name may not contain any slash; it is the name of the symbolic link to be created in the present directory. For instance, if a page named dir.html exists in the /dir directory, and index.html does not exist, /dir/.symlinks should contain a line like this:

dir.html index.html

The ln -s analogy accounts for only part of the story. The current method actually takes advantage of the flexibility of URL rewriting. Thus a single HTML entry in the .symlinks file defines links to all possible translations that follow our naming conventions. This makes it impossible to use symlinks to redirect to and from HTML files whose names look like translations, that is, page.ll.html or page.ll-cc.html, where ll and cc are two-letter codes. When you need such redirections, use the htaccess mechanism.

These days, the .symlinks handling happens on www.gnu.org via a cron job that runs twice an hour. Webmasters do not have access to it.

.htaccess and redirections

To browsers, the symbolic links in the previous section are indistinguishable from the actual file. You may want an actual redirection in some cases. You can do this either in the top-level control file .htaccess, or by using something like this as the file to be redirected:

<meta http-equiv="refresh" content="0; url=https://www.gnu.org/target">

Server-side scripts

A description of scripts and software used on www.gnu.org is available. Please read it before writing any scripts, and also update it as needed if you have write access to www.

System administrators

The system administrators for GNU change from time to time. Please email the sysadmin list <sysadmin@gnu.org> rather than an individual, unless you have a specific reason to do so.

Useful Resources

• Outside gnu.org:
  • We follow the guidelines of the Best Viewed with Any Browser campaign.
  • Basic info on the web and its technical specifications can be found at The World Wide Web Consortium.
  • The GNU web server follows the w3.org Style Guide.
  • Use of WCAG 2.1 helps ensure accessibility for a wide range of people with disabilities.
• On gnu.org:
  • The GNU Website Guidelines (this page);
  • Guidelines for Web Page Creation at www.gnu.org;
  • Appendix B Tips and Hints, and other style tips in the Texinfo Manual;
  • GNU Accessibility Statement;
  • GNU Webmastering Guidelines;
  • Guide to translating GNU web pages into other languages;
  • Tips for webmasters to make translators' job easier;
  • Documentation for Savannah, the SourceForge clone dedicated to the GNU Project.
  • How to help with our web server and other tasks.