Help:URL

URLs in external links
A link in external link style can be of the forms:
 * target: http://meta.wikimedia.org/ is rendered as http://meta.wikimedia.org/
 * [ target label ], with a blank space in between: wikimedia gives wikimedia (see also Help:Piped link)
 * [ target ] - these are automatically labelled with serial numbers 1, 2, 3, ...: gives

The target is a URL which can start with " http:// " or " ftp:// ";

"file://" does not work by default. If enabled it only works in MSIE. To enable it, add a $wgUrlProtocols entry to LocalSettings.php; see the $wgUrlProtocols in DefaultSettings.php for example.

All characters of the URL must be among: A-Z a-z 0-9 ._\/~%-+&amp;#?!=@

If a URL contains a different character it should be converted; for example, ^ has to be written %5e, the hexadecimal ASCII value with a percent sign in front. A blank space can also be converted into an underscore.

Conversion:

"  #   $   %   &amp;   '     *  ,   :   ;  %20 %22 %23 %24 %25 %26 %27 %28 %29 %2a %2c %3a %3b

<  >   ?   [   ]   ^   `   {   |   } %3c %3e %3f %5b %5d %5e %60 %7b %7c %7d

For the other characters either the code or the character can be used in internal and external links, they are equivalent. The system does a conversion when needed. E.g.

%C3%80_propos_de_M%C3%A9ta

is rendered as %C3%80_propos_de_M%C3%A9ta, almost like À propos de Méta, which leads to this page on Meta with in the address bar the URL

http://meta.wikipedia.org/wiki/%C3%80_propos_de_M%C3%A9ta

while http://meta.wikipedia.org/wiki/À_propos_de_Méta leads to the same.

There is an external online converter (JavaScript, GPL) for percent-encoding a string available.

See also (in Wikipedia): Internationalized domain names and Punycode.

Percent-encoding
For ASCII characters (up to decimal 127, hex. 7F) percent-encoding simply means adding % to the hex. value, e.g. for a tilde ~ (decimal 126, hex. 7E) it's %7E. Otherwise (non-ASCII) convert it first to UTF-8 and then percent-encode it. Example:


 * 1) Convert the character to Unicode, e.g. Latin-1 192 (hex. C0) to À (u+00C0), or windows-1252 131 (hex. 8B) to &#x160; (u+0160).
 * 2) Convert Unicode to bits, 00000000 11000000 (u+00C0), or 00000001 01100000 (u+0160).
 * 3) Build groups of six bits from the right adding leading zeros if necessary until the rest are zeros: 000011 000000 (u+00C0), or 000101 100000 (u+0160).
 * 4) Add 10 in front of all but the leftmost group. 2 bits + 6 bits = 8bits, also known as octet.
 * 5) If there are only two groups, and the first (left) starts with 0:
 * 6) Add 11 to the left: 11 000011 10 0000000 (u+00C0), or 11 000101 10 100000 (u+0160).
 * 7) Convert the octets to hex., add percent in front, ready: %C3%80 (u+00C0), or %C5%A0 (u+0160).
 * 8) If the first (left) of two groups starts with 1:
 * Add 111 00000 10 to the left, then percent-encode three octects, %E0%??%??
 * 1) If there are three groups, the first (left) starting with 00 (000001 up to 001111):
 * Replace 00 by 111 0, percent-encode three octects, ready, result %E?%??%??.
 * 1) Otherwise it's at least 010000 000000 000000 (u+10000) needing four UTF-8 octets:
 * 1111 0000 10 010000 10 000000 10 000000 would be %F0%90%80%80.

There is an external online converter (JavaScript, GPL) for percent-encoding a string available.

URLs of pages within the projects
See w:Wikipedia:URLs. On other projects everything works the same, except that the domain names vary:


 * xx.wikipedia.org with xx the language code, see Complete list of language Wikipedias available
 * meta.wikimedia.org (meta.wikipedia.org redirects there)
 * xx.wiktionary.org
 * xx.wikiquote.org
 * xx.wikibooks.org
 * xx.wikisource.org
 * sep11.wikipedia.org

A URL starting with www.wikipedia.org redirects to the corresponding one starting with en; only www.wikipedia.org itself leads to a portal page instead of the main page of the English Wikipedia: http://www.wikipedia.org

In projects outside Wikimedia the "w/" in URLs like http://www.wikipedia.org/w/wiki.phtml?title=Main_Page&action=history is sometimes not used, sometimes different, e.g.:
 * http://www.disinfopedia.org/wiki.phtml?title=Disinfopedia_Main_Page&action=history
 * http://wikitravel.org/en/index.php?title=Main_Page&action=history

The default is /wiki/wiki.phtml, with in DefaultSetting.php :

$wgScriptPath = "/wiki"; $wgScript    = "{$wgScriptPath}/wiki.phtml";

There may be other variations, compare:
 * http://en.wikipedia.org/wiki/Vancouver
 * http://wikitravel.org/en/Vancouver

Use in templates
For use in templates, note that all URLs on e.g. the English Wikipedia can be written in the form

http:// en.wikipedia.org/w/index.php?title=

This requires to be written with underscores and escape codes (if applicable), or can be escaped with. To benefit from the conversion carried out by fullurl, two parameters are needed:

(see Template talk:Url 2p). An example with the second parameter in fullurl fixed is ed containing the link [ ].

This works for a link in external link style to a page in the same project. We can use localurl for a link to a project which uses the same string in the URL between the server name and the question mark ($wgScript, on Wikimedia "/w/index.php"), but not for links to other projects.

Old versions of pages
All old versions of all pages are numbered (with oldid) approximately in the order of becoming an old version, i.e. in chronological order of the next edit of the same page.


 * http://meta.wikimedia.org/w/wiki.phtml?title=Help:Link&oldid=53587 - normal link to old page
 * http://meta.wikimedia.org/w/wiki.phtml?oldid=53587 - no page name in the URL, goes to the correct page
 * http://meta.wikimedia.org/w/wiki.phtml?title=Help:Link&oldid=53588 - number and name do not correspond; the name is ignored
 * http://meta.wikimedia.org/w/wiki.phtml?title=abc&oldid=53587 - non-existing page name; oldid is ignored, works like going to a non-existing page, except for the links to assumed previous and next versions, and on editing, for the warning of editing an old version of a page.

See also Linking to specific versions of a page.

New pages
Pages are numbered with page_id (see Page table) in order of creation.


 * http://meta.wikimedia.org/w/wiki.phtml?title=x&curid=9906 - gives the page with correct full name

Conversely, most query output provides page names as well as page id's, e.g. http://meta.wikimedia.org/w/query.php?titles=Hilfe:Zeitleiste

See also Multiple titles.

From MediaWiki 1.5 page versions get a number "oldid" as soon as they are created; they are produced by variable. The URL is like in the previous section.

Edit
Examples:


 * Edit the whole page: http://meta.wikimedia.org/w/wiki.phtml?title=Help:URL&action=edit
 * Edit the 5th section: http://meta.wikimedia.org/w/wiki.phtml?title=Help:URL&action=edit&section=5
 * Add at the end: http://meta.wikimedia.org/w/wiki.phtml?title=Help:URL&action=edit&section=1000 (use large section number)
 * Ditto with "Post a comment" feature: http://meta.wikimedia.org/w/wiki.phtml?title=Help:URL&action=edit&section=new

Purge
In some cases of caching problems, to update a page it can help to use "action=purge", in a URL like which results in:

Uselang
In some cases it is helpful to link to another Wikimedia project by using the "&uselang" parameter, in a URL like http://commons.wikimedia.org/w/index.php?title=Glavna_stran&uselang=sl. This allows specifying the language (hereby Slovenian) of the interface messages that will be displayed when opening the page 'Glavna stran' in the Commons project.

Miscellaneous actions
You can fetch the raw wikitext of a page using a URL like which results here in:

Other actions are view, watch, unwatch, delete, revert, rollback, unprotect, info, markpatrolled, validate, render, deletetrackback, and history. (These rarely need to be entered explicitly, as the useful ones are prelinked at various tabs and buttons. Several of these actions require administrator privileges. Other users do not have the link; if they try the URL they get the message in MediaWiki:Badaccesstext.)

Kinds of dead links
There can be various kinds of errors in the URL. With some the server is not even reached, with others the server takes some action. The server may also go to the correct page and just ignore a wrong parameter or anchor.


 * http://meta.wikimedia.or/
 * abc
 * http://met.mediawiki.org
 * /abc
 * http://meta.wikimedia.org/w/index.php?title=Help:URL&action=abc
 * http://meta.wikimedia.org/w/index.php?title=Help:URL&act=abc
 * http://meta.wikimedia.org/w/index.php?title=Help:URL#abc
 * http://meta.wikimedia.org/w/index.php?title=Help:URL#abc