- From: Art Barstow via cvs-syncmail <cvsmail@w3.org>
- Date: Wed, 28 Sep 2011 14:06:33 +0000
- To: public-html-commits@w3.org
Update of /sources/public/html5/websockets/publish
In directory hutz:/tmp/cvs-serv377
Added Files:
LCWD-websockets-20110929.html
Log Message:
29-Sep-2011 LCWD; based on v1.242
--- NEW FILE: LCWD-websockets-20110929.html ---
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"><html lang="en-US-x-Hixie"><title>The WebSocket API</title><style type="text/css">
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<p><a href="http://www.w3.org/"><img alt="W3C" height="48" src="http://www.w3.org/Icons/w3c_home" width="72"></a></p>
<h1>The WebSocket API</h1>
<h2 class="no-num no-toc" id="working-draft-29-september-2011">W3C Working Draft 29 September 2011</h2>
<dl>
<dt>This Version:</dt>
<dd><a href="http://www.w3.org/TR/2011/WD-websockets-20110929/">http://www.w3.org/TR/2011/WD-websockets-20110929/</a></dd>
<dt>Latest Published Version:</dt>
<dd><a href="http://www.w3.org/TR/websockets/">http://www.w3.org/TR/websockets/</a></dd>
<dt>Latest Editor's Draft:</dt>
<dd><a class="latest-link" href="http://dev.w3.org/html5/websockets/">http://dev.w3.org/html5/websockets/</a></dd>
<dt>Previous Versions:</dt>
<dd><a href="http://www.w3.org/TR/2011/WD-websockets-20110419/">http://www.w3.org/TR/2011/WD-websockets-20110419/</a></dd>
<dd><a href="http://www.w3.org/TR/2009/WD-websockets-20091222/">http://www.w3.org/TR/2009/WD-websockets-20091222/</a></dd>
<dd><a href="http://www.w3.org/TR/2009/WD-websockets-20091029/">http://www.w3.org/TR/2009/WD-websockets-20091029/</a></dd>
<dd><a href="http://www.w3.org/TR/2009/WD-websockets-20090423/">http://www.w3.org/TR/2009/WD-websockets-20090423/</a>
<!-- :ZZZ -->
<dt>Editor:</dt>
<dd><a href="mailto:ian@hixie.ch">Ian Hickson</a>, Google, Inc.</dd>
</dl><p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a>
© 2011 <a href="http://www.w3.org/"><abbr title="World Wide
Web Consortium">W3C</abbr></a><sup>®</sup> (<a href="http://www.csail.mit.edu/"><abbr title="Massachusetts
Institute of Technology">MIT</abbr></a>, <a href="http://www.ercim.eu/"><abbr title="European Research
Consortium for Informatics and Mathematics">ERCIM</abbr></a>, <a href="http://www.keio.ac.jp/">Keio</a>), All Rights Reserved. W3C
<a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>,
<a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a>
and <a href="http://www.w3.org/Consortium/Legal/copyright-documents">document
use</a> rules apply.</p>
<!-- UNDER NO CIRCUMSTANCES IS THE FOLLOWING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST -->
<p class="alt">The bulk of the text of this specification is also
available in the WHATWG <a href="http://www.whatwg.org/specs/web-apps/current-work/complete.html#network">Web Applications 1.0</a> specification, under a license that permits
reuse of the specification text.</p>
<!-- UNDER NO CIRCUMSTANCES IS THE PRECEDING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST -->
</div><hr class="top"><h2 class="no-num no-toc" id="abstract">Abstract</h2><p>This specification defines an API that enables Web pages to use
the WebSocket protocol for two-way communication with a remote
host.<h2 class="no-num no-toc" id="status-of-this-document">Status of This document</h2><p><em>This section describes the status of this document at the
time of its publication. Other documents may supersede this
document. A list of current W3C publications and the
most recently formally published <!-- DO NOT CHANGE THIS BACK TO THE STANDARD BOILERPLATE, AS IT IS INACCURATE -->
revision of this technical report can be found in the <a href="http://www.w3.org/TR/">W3C technical reports index</a> at
http://www.w3.org/TR/.</em></p><p>If you wish to make comments regarding this document in a manner
that is tracked by the W3C, please submit them via using <a href="http://www.w3.org/Bugs/Public/enter_bug.cgi?product=HTML%20WG">our
public bug database</a>. If you do not have an account then you can
enter feedback using this form:<form action="http://www.whatwg.org/specs/web-apps/current-work/file-spam.cgi" method="post">
<fieldset><legend>Feedback Comments</legend>
<input name="id" type="hidden" value="top"><input name="component" type="hidden" value="WebSocket API (editor: Ian Hickson)"><input name="response" type="hidden" value="html"><p><label for="feedbackBox">Please enter your feedback, carefully
indicating the title of the section for which you are submitting
feedback, quoting the text that's wrong today if appropriate. If
you're suggesting a new feature, it's really important to say
<em>what</em> the problem you're trying to solve is. That's more
important than the solution, in fact.</label></p>
<p><textarea cols="79" id="feedbackBox" name="text" rows="10"></textarea></p>
<p class="note">Please don't use section numbers as these tend to
change rapidly and make your feedback harder to understand.</p>
<script type="text/javascript">
function checkFeedbackForm(form) {
if (form.elements.text.value.match(/^ *</)) {
alert('Please don\'t start your feedback with an angle bracket, instead explain what topic your feedback is about first.');
return true;
} else if (form.elements.text.value.match(/ [^ ]+ [^ ]+ [^ ]+ [^ ]+ /)) {
if (form.elements.text.value.match(/^Please enter your feedback, carefully/)) {
alert('Please enter your feedback, explaining what is wrong, and without repeating the instructions. Thanks!');
return true;
} else if (form.elements.text.value.match(/ [^ ]+ [^ ]+ [^ ]+ [^ ]+ /)) {
form.action = "http://www.whatwg.org/specs/web-apps/current-work/file-bug.cgi";
return true;
} else {
alert('Please include significantly more detail about exactly what problem you are trying to solve.');
return false;
}
}
}
</script><p>
<input onclick="return checkFeedbackForm(form)" type="submit" value="Submit feedback"><small>(Note: Your IP address and user agent will be publicly recorded for spam prevention purposes.)</small>
</p>
</fieldset></form><p>You can also e-mail feedback to <a href="mailto:public-webapps@w3.org">public-webapps@w3.org</a> (<a href="mailto:public-webapps-request@w3.org?subject=subscribe">subscribe</a>,
<a href="http://lists.w3.org/Archives/Public/public-webapps/">archives</a>),
or <a href="mailto:whatwg@whatwg.org">whatwg@whatwg.org</a> (<a href="http://lists.whatwg.org/listinfo.cgi/whatwg-whatwg.org">subscribe</a>,
<a href="http://lists.whatwg.org/pipermail/whatwg-whatwg.org/">archives</a>).
All feedback is welcome.</p><p>
<strong>Implementors who are not taking part in the
discussions are likely to find the specification changing out from
under them in incompatible ways.</strong> Vendors interested in
implementing this specification before it eventually reaches the
Candidate Recommendation stage should join the aforementioned
mailing lists and take part in the discussions.<div id="multipage-common">
</div><p>The latest
stable version of the editor's draft of this specification is always
available on <a href="http://dev.w3.org/html5/websockets/">the W3C CVS server</a>
and in the <a href="http://svn.whatwg.org/webapps/">WHATWG
Subversion repository</a>. The <a href="http://www.whatwg.org/specs/web-apps/current-work/complete.html">latest
editor's working copy</a> (which may contain unfinished text in the
process of being prepared) contains the latest draft text of this
specification (amongst others). For more details, please see the <a href="http://wiki.whatwg.org/wiki/FAQ#What_are_the_various_versions_of_the_spec.3F">WHATWG
FAQ</a>.<p>Notifications of changes to this specification are sent along
with notifications of changes to related specifications using the
following mechanisms:<dl><dt>E-mail notifications of changes</dt>
<dd>Commit-Watchers mailing list (complete source diffs): <a href="http://lists.whatwg.org/listinfo.cgi/commit-watchers-whatwg.org">http://lists.whatwg.org/listinfo.cgi/commit-watchers-whatwg.org</a></dd>
<dt>Browsable version-control record of all changes:</dt>
<dd>CVSWeb interface with side-by-side diffs: <a href="http://dev.w3.org/cvsweb/html5/">http://dev.w3.org/cvsweb/html5/</a></dd>
<dd>Annotated summary with unified diffs: <a href="http://html5.org/tools/web-apps-tracker">http://html5.org/tools/web-apps-tracker</a></dd>
<dd>Raw Subversion interface: <code>svn checkout http://svn.whatwg.org/webapps/</code></dd>
</dl><p>The W3C <a href="http://www.w3.org/2008/webapps/">Web Applications
Working Group</a> is the W3C working group responsible for this
specification's progress along the W3C Recommendation track.
This specification is the 29 September 2011 Last Call Working Draft.
The Last Call review period will end on 21 October 2011. </p>
<p>This specification is being developed in conjunction with an
Internet Draft for a wire protocol, the WebSocket Protocol,
available from the following location:<ul><li>WebSocket Protocol Internet-Draft: <a href="http://www.whatwg.org/specs/web-socket-protocol/">http://www.whatwg.org/specs/web-socket-protocol/</a></li>
</ul>
<p>This document was produced by a group operating under the <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5
February 2004 W3C Patent Policy</a>. W3C maintains a <a href="http://www.w3.org/2004/01/pp-impl/42538/status" rel="disclosure">public list of
any patent disclosures</a> made in connection with the deliverables
of the group; that page also includes instructions for disclosing a
patent. An individual who has actual knowledge of a patent which the
individual believes contains <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential
Claim(s)</a> must disclose the information in accordance with <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section
6 of the W3C Patent Policy</a>.</p>
<h2 class="no-num no-toc" id="contents">Table of Contents</h2>
<ol class="toc">
<li><a href="#network-intro"><span class="secno">1 </span>Introduction</a></li>
<li><a href="#conformance-requirements"><span class="secno">2 </span>Conformance requirements</a>
<ol>
<li><a href="#dependencies"><span class="secno">2.1 </span>Dependencies</a></ol></li>
<li><a href="#terminology"><span class="secno">3 </span>Terminology</a></li>
<li><a href="#the-websocket-interface"><span class="secno">4 </span>The <code>WebSocket</code> interface</a></li>
<li><a href="#feedback-from-the-protocol"><span class="secno">5 </span>Feedback from the protocol</a>
<ol>
<li><a href="#event-definitions"><span class="secno">5.1 </span>Event definitions</a></li>
<li><a href="#garbage-collection"><span class="secno">5.2 </span>Garbage collection</a></ol></li>
<li><a class="no-num" href="#references">References</a></li>
<li><a class="no-num" href="#acknowledgements">Acknowledgements</a></ol>
<hr><h2 id="network-intro"><span class="secno">1 </span>Introduction</h2><p><i>This section is non-normative.</i><p>To enable Web applications to maintain bidirectional
communications with server-side processes, this specification
introduces the <code><a href="#websocket">WebSocket</a></code> interface.<p class="note">This interface does not allow for raw access to the
underlying network. For example, this interface could not be used to
implement an IRC client without proxying messages through a custom
server.<h2 id="conformance-requirements"><span class="secno">2 </span>Conformance requirements</h2><p>All diagrams, examples, and notes in this specification are
non-normative, as are all sections explicitly marked non-normative.
Everything else in this specification is normative.<p>The key words "MUST", "MUST NOT", "REQUIRED", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and
"OPTIONAL" in the normative parts of this document are to be
interpreted as described in RFC2119. For readability, these words do
not appear in all uppercase letters in this specification. <a href="#refsRFC2119">[RFC2119]</a><p>Requirements phrased in the imperative as part of algorithms
(such as "strip any leading space characters" or "return false and
abort these steps") are to be interpreted with the meaning of the
key word ("must", "should", "may", etc) used in introducing the
algorithm.<p>Some conformance requirements are phrased as requirements on
attributes, methods or objects. Such requirements are to be
interpreted as requirements on user agents.<p>Conformance requirements phrased as algorithms or specific steps
may be implemented in any manner, so long as the end result is
equivalent. (In particular, the algorithms defined in this
specification are intended to be easy to follow, and not intended to
be performant.)<p>The only conformance class defined by this specification is user
agents.<p>User agents may impose implementation-specific limits on
otherwise unconstrained inputs, e.g. to prevent denial of service
attacks, to guard against running out of memory, or to work around
platform-specific limitations.<p>When support for a feature is disabled (e.g. as an emergency
measure to mitigate a security problem, or to aid in development, or
for performance reasons), user agents must act as if they had no
support for the feature whatsoever, and as if the feature was not
mentioned in this specification. For example, if a particular
feature is accessed via an attribute in a Web IDL interface, the
attribute itself would be omitted from the objects that implement
that interface — leaving the attribute on the object but
making it return null or throw an exception is insufficient.<h3 id="dependencies"><span class="secno">2.1 </span>Dependencies</h3><p>This specification relies on several other underlying
specifications.<dl><dt>HTML</dt>
<dd>
<p>Many fundamental concepts from HTML are used by this
specification. <a href="#refsHTML">[HTML]</a></p>
</dd>
<dt>WebIDL</dt>
<dd>
<p>The IDL blocks in this specification use the semantics of the
WebIDL specification. <a href="#refsWEBIDL">[WEBIDL]</a></p>
</dd>
</dl><h2 id="terminology"><span class="secno">3 </span>Terminology</h2><p>The construction "a <code title="">Foo</code> object", where
<code title="">Foo</code> is actually an interface, is sometimes
used instead of the more accurate "an object implementing the
interface <code title="">Foo</code>".<p>The term DOM is used to refer to the API set made available to
scripts in Web applications, and does not necessarily imply the
existence of an actual <code>Document</code> object or of any other
<code>Node</code> objects as defined in the DOM Core
specifications. <a href="#refsDOMCORE">[DOMCORE]</a><p>An IDL attribute is said to be <em>getting</em> when its value is
being retrieved (e.g. by author script), and is said to be
<em>setting</em> when a new value is assigned to it.<h2 id="the-websocket-interface"><span class="secno">4 </span>The <code><a href="#websocket">WebSocket</a></code> interface</h2><pre class="idl">[<a href="#dom-websocket" title="dom-WebSocket">Constructor</a>(DOMString url, optional DOMString protocols),
<a href="#dom-websocket" title="dom-WebSocket">Constructor</a>(DOMString url, optional DOMString[] protocols)]
interface <dfn id="websocket">WebSocket</dfn> : <span>EventTarget</span> {
readonly attribute DOMString <a href="#dom-websocket-url" title="dom-WebSocket-url">url</a>;
// ready state
const unsigned short <a href="#dom-websocket-connecting" title="dom-WebSocket-CONNECTING">CONNECTING</a> = 0;
const unsigned short <a href="#dom-websocket-open" title="dom-WebSocket-OPEN">OPEN</a> = 1;
const unsigned short <a href="#dom-websocket-closing" title="dom-WebSocket-CLOSING">CLOSING</a> = 2;
const unsigned short <a href="#dom-websocket-closed" title="dom-WebSocket-CLOSED">CLOSED</a> = 3;
readonly attribute unsigned short <a href="#dom-websocket-readystate" title="dom-WebSocket-readyState">readyState</a>;
readonly attribute unsigned long <a href="#dom-websocket-bufferedamount" title="dom-WebSocket-bufferedAmount">bufferedAmount</a>;
// networking
attribute <span>Function</span>? <a href="#handler-websocket-onopen" title="handler-WebSocket-onopen">onopen</a>;
attribute <span>Function</span>? <a href="#handler-websocket-onerror" title="handler-WebSocket-onerror">onerror</a>;
attribute <span>Function</span>? <a href="#handler-websocket-onclose" title="handler-WebSocket-onclose">onclose</a>;
readonly attribute DOMString <a href="#dom-websocket-extensions" title="dom-WebSocket-extensions">extensions</a>;
readonly attribute DOMString <a href="#dom-websocket-protocol" title="dom-WebSocket-protocol">protocol</a>;
void <a href="#dom-websocket-close" title="dom-WebSocket-close">close</a>([Clamp] optional unsigned short code, optional DOMString reason);
// messaging
attribute <span>Function</span>? <a href="#handler-websocket-onmessage" title="handler-WebSocket-onmessage">onmessage</a>;
attribute DOMString <a href="#dom-websocket-binarytype" title="dom-WebSocket-binaryType">binaryType</a>;
void <a href="#dom-websocket-send" title="dom-WebSocket-send">send</a>(DOMString data);
void <a href="#dom-websocket-send" title="dom-WebSocket-send">send</a>(<span>ArrayBuffer</span> data);
void <a href="#dom-websocket-send" title="dom-WebSocket-send">send</a>(<span>Blob</span> data);
};</pre><p>The <dfn id="dom-websocket" title="dom-WebSocket"><code>WebSocket(<var title="">url</var>, <var title="">protocols</var>)</code></dfn>
constructor takes one or two arguments. The first argument, <var title="">url</var>, specifies the <span>URL</span> to which to
connect. The second, <var title="">protocols</var>, if present, is
either a string or an array of strings. If it is a string, it is
equivalent to an array consisting of just that string; if it is
omitted, it is equivalent to the empty array. Each string in the
array is a subprotocol name. The connection will only be established
if the server reports that it has selected one of these
subprotocols. The subprotocol names must all be strings that match
the requirements for elements that comprise the value of <code title="http-sec-websocket-protocol">Sec-WebSocket-Protocol</code>
header fields as defined by the WebSocket protocol specification. <a href="#refsWSP">[WSP]</a><p>When the <code>WebSocket()</code> constructor is invoked, the UA
must run these steps:<ol><li><p><i>Parse a WebSocket URL's components</i> from the <var title="">url</var> argument, to obtain <var title="">host</var>,
<var title="">port</var>, <var title="">resource name</var>, and
<var title="">secure</var>. If this fails, throw a
<code>SYNTAX_ERR</code> exception and abort these steps. <a href="#refsWSP">[WSP]</a></li>
<li><p>If <var title="">secure</var> is false but the
<span>origin</span> of the <span>entry script</span> has a scheme
component that is itself a secure protocol, e.g. HTTPS, then throw
a <code>SECURITY_ERR</code> exception.</li>
<li>
<p>If <var title="">port</var> is a port to which the user agent
is configured to block access, then throw a
<code>SECURITY_ERR</code> exception. (User agents typically block
access to well-known ports like SMTP.)</p>
<p>Access to ports 80 and 443 should not be blocked, including the
unlikely cases when <var title="">secure</var> is false but <var title="">port</var> is 443 or <var title="">secure</var> is true
but <var title="">port</var> is 80.</p>
</li>
<li>
<p>If <var title="">protocols</var> is absent, let <var title="">protocols</var> be an empty array.</p>
<p>Otherwise, if <var title="">protocols</var> is present and a
string, let <var title="">protocols</var> instead be an array
consisting of just that string.</p>
</li>
<li><p>If any of the values in <var title="">protocols</var> occur
more than once or otherwise fail to match the requirements for
elements that comprise the value of <code title="http-sec-websocket-protocol">Sec-WebSocket-Protocol</code>
header fields as defined by the WebSocket protocol specification,
then throw a <code>SYNTAX_ERR</code> exception and abort these
steps. <a href="#refsWSP">[WSP]</a></li>
<li><p>Let <var title="">origin</var> be the <span title="ASCII
serialization of an origin">ASCII serialization</span> of the
<span>origin</span> of the <span>entry script</span>,
<span>converted to ASCII lowercase</span>.</li>
<li><p>Return a new <code><a href="#websocket">WebSocket</a></code> object, and continue
these steps in the background (without blocking scripts).</li>
<li>
<p><i>Establish a WebSocket connection</i> given the set (<var title="">host</var>, <var title="">port</var>, <var title="">resource name</var>, <var title="">secure</var>), along
with the <var title="">protocols</var> list, an empty list for the
extensions, and <var title="">origin</var>. The <i>headers to send
appropriate cookies</i> must be a <code title="http-Cookie">Cookie</code> header whose value is the
<i>cookie-string</i> computed from the user's cookie store and the
URL <var title="">url</var>; for these purposes this is
<em>not</em> a "non-HTTP" API. <a href="#refsWSP">[WSP]</a> <a href="#refsCOOKIES">[COOKIES]</a></p>
<p>When the user agent <i title="validate the server's
response">validates the server's response</i> during the
"<i>establish a WebSocket connection</i>" algorithm, if the status
code received from the server is not 101 (e.g. it is a redirect),
the user agent must <i>fail the websocket connection</i>.</p>
<p class="warning">Following HTTP procedures here could introduce
serious security problems in a Web browser context. For example,
consider a host with a WebSocket server at one path and an open
HTTP redirector at another. Suddenly, any script that can be given
a particular WebSocket URL can be tricked into communicating to
(and potentially sharing secrets with) any host on the Internet,
even if the script checks that the URL has the right hostname.</p>
<p class="note">If the <i>establish a WebSocket connection</i>
algorithm fails, it triggers the <i>fail the WebSocket
connection</i> algorithm, which then invokes the <i>close the
WebSocket connection</i> algorithm, which then establishes that
<i>the WebSocket connection is closed</i>, which fires the <code title="event-close">close</code> event <a href="#closeWebSocket">as described below</a>.</p>
</li>
</ol><p>This constructor must be visible when the <span>script's global
object</span> is either a <code>Window</code> object or an object
implementing the <code>WorkerUtils</code> interface.<hr><p>The <dfn id="dom-websocket-url" title="dom-WebSocket-url"><code>url</code></dfn>
attribute must return the result of <span title="resolve a
url">resolving</span> the <span>URL</span> that was passed to the
constructor. (It doesn't matter what it is resolved relative to,
since we already know it is an <span>absolute URL</span>.)<p>The <dfn id="dom-websocket-readystate" title="dom-WebSocket-readyState"><code>readyState</code></dfn>
attribute represents the state of the connection. It can have the
following values:<dl><dt><dfn id="dom-websocket-connecting" title="dom-WebSocket-CONNECTING"><code>CONNECTING</code></dfn> (numeric value 0)</dt>
<dd>The connection has not yet been established.</dd>
<dt><dfn id="dom-websocket-open" title="dom-WebSocket-OPEN"><code>OPEN</code></dfn> (numeric value 1)</dt>
<dd><i>The WebSocket connection is established</i> and communication is possible.</dd>
<dt><dfn id="dom-websocket-closing" title="dom-WebSocket-CLOSING"><code>CLOSING</code></dfn> (numeric value 2)</dt>
<dd>The connection is going through the closing handshake.</dd>
<dt><dfn id="dom-websocket-closed" title="dom-WebSocket-CLOSED"><code>CLOSED</code></dfn> (numeric value 3)</dt>
<dd>The connection has been closed or could not be opened.</dd>
</dl><p>When the object is created its <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code> must be set to
<code title="dom-WebSocket-CONNECTING"><a href="#dom-websocket-connecting">CONNECTING</a></code> (0).<p>The <dfn id="dom-websocket-extensions" title="dom-WebSocket-extensions"><code>extensions</code></dfn>
attribute must initially return the empty string. After <i>the
WebSocket connection is established</i>, its value might change, as
defined below.<p class="note">The <code title="dom-WebSocket-extensions"><a href="#dom-websocket-extensions">extensions</a></code> attribute returns
the extensions selected by the server, if any. (Currently this will
only ever be the empty string.)<p>The <dfn id="dom-websocket-protocol" title="dom-WebSocket-protocol"><code>protocol</code></dfn> attribute
must initially return the empty string. After <i>the WebSocket
connection is established</i>, its value might change, as defined
below.<p class="note">The <code title="dom-WebSocket-protocol"><a href="#dom-websocket-protocol">protocol</a></code> attribute returns the
subprotocol selected by the server, if any. It can be used in
conjunction with the array form of the constructor's second argument
to perform subprotocol negotiation.<p>The <dfn id="dom-websocket-close" title="dom-WebSocket-close"><code>close()</code></dfn>
method must run the following steps:<ol><li><p>If the method's first argument is present but is not an
integer equal to 1000 or in the range 3000 to 4999, throw an
<code>INVALID_ACCESS_ERR</code> exception and abort these
steps.</li>
<li><p>If the method's second argument has any unpaired surrogates,
then throw a <code>SYNTAX_ERR</code> exception and abort these
steps.</li>
<li><p>If the method's second argument is present, then let <var title="">reason</var> be the result of encoding that argument as
UTF-8. If <var title="">reason</var> is longer than 123 bytes, then
throw a <code>SYNTAX_ERR</code> exception and abort these steps.
<a href="#refsRFC3629">[RFC3629]</a></li>
<li><p>Run the first matching steps from the following list:</p>
<dl class="switch"><dt>If the <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code>
attribute is in the <code title="dom-WebSocket-CLOSING"><a href="#dom-websocket-closing">CLOSING</a></code> (2) or <code title="dom-WebSocket-CLOSED"><a href="#dom-websocket-closed">CLOSED</a></code> (3) state</dt>
<dd>
<p>Do nothing.</p>
<p class="note">The connection is already closing or is already
closed. If it has not already, a <code title="event-close">close</code> event will eventually fire <a href="#closeWebSocket">as described below</a>.</p>
</dd>
<dt>If the WebSocket connection is not yet <i title="the
WebSocket connection is established">established</i> <a href="#refsWSP">[WSP]</a></dt>
<dd>
<p><i>Fail the WebSocket connection</i> and set the <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code> attribute's
value to <code title="dom-WebSocket-CLOSING"><a href="#dom-websocket-closing">CLOSING</a></code> (2).
<a href="#refsWSP">[WSP]</a></p>
<p class="note">The <i>fail the WebSocket connection</i>
algorithm invokes the <i>close the WebSocket
connection</i> algorithm, which then establishes that
<i>the WebSocket connection is closed</i>, which fires the
<code title="event-close">close</code> event <a href="#closeWebSocket">as described below</a>.</p>
</dd>
<dt>If the WebSocket closing handshake has not yet been <i title="the WebSocket closing handshake is
started">started</i> <a href="#refsWSP">[WSP]</a></dt>
<dd>
<p><i>Start the WebSocket closing handshake</i> and set the
<code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code>
attribute's value to <code title="dom-WebSocket-CLOSING"><a href="#dom-websocket-closing">CLOSING</a></code> (2). <a href="#refsWSP">[WSP]</a></p>
<p>If the first argument is present, then the status
code<!--CLOSE CODE--> to use in the WebSocket Close message must
be the integer given by the first argument. <a href="#refsWSP">[WSP]</a></p>
<p>If the second argument is also present, then <var title="">reason</var> must be provided in the Close message
after the status code<!--CLOSE CODE-->. <a href="#refsRFC3629">[RFC3629]</a> <a href="#refsWSP">[WSP]</a></p>
<p class="note">The <i>start the WebSocket closing handshake</i>
algorithm eventually invokes the <i>close the WebSocket
connection</i> algorithm, which then establishes that <i>the
WebSocket connection is closed</i>, which fires the <code title="event-close">close</code> event <a href="#closeWebSocket">as described below</a>.</p>
</dd>
<dt>Otherwise</dt>
<dd>
<p>Set the <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code> attribute's
value to <code title="dom-WebSocket-CLOSING"><a href="#dom-websocket-closing">CLOSING</a></code>
(2).</p>
<p class="note"><i>The WebSocket closing handshake is
started</i>, and will eventually invoke the <i>close the
WebSocket connection</i> algorithm, which will establish that
<i>the WebSocket connection is closed</i>, and thus the <code title="event-close">close</code> event will fire, <a href="#closeWebSocket">as described below</a>.</p>
</dd>
</dl></li>
</ol><hr><p>The <dfn id="dom-websocket-bufferedamount" title="dom-WebSocket-bufferedAmount"><code>bufferedAmount</code></dfn>
attribute must return the number of bytes of application data (UTF-8
text and binary data) that have been queued using <code title="dom-WebSocket-send"><a href="#dom-websocket-send">send()</a></code> but that, as of the last
time the <span>event loop</span> started executing a <span title="concept-task">task</span>, had not yet been transmitted to
the network. (This thus includes any text sent during the execution
of the current task, regardless of whether the user agent is able to
transmit text asynchronously with script execution.) This does not
include framing overhead incurred by the protocol, or buffering done
by the operating system or network hardware. If the connection is
closed, this attribute's value will only increase with each call to
the <code title="dom-WebSocket-send"><a href="#dom-websocket-send">send()</a></code> method (the
number does not reset to zero once the connection closes).<div class="example">
<p>In this simple example, the <code title="dom-WebSocket-bufferedAmount"><a href="#dom-websocket-bufferedamount">bufferedAmount</a></code>
attribute is used to ensure that updates are sent either at the
rate of one update every 50ms, if the network can handle that rate,
or at whatever rate the network <em>can</em> handle, if that is too
fast.</p>
<pre>var socket = new WebSocket('ws://game.example.com:12010/updates');
socket.onopen = function () {
setInterval(function() {
if (socket.bufferedAmount == 0)
socket.send(getUpdateData());
}, 50);
};</pre>
<p>The <code title="dom-WebSocket-bufferedAmount"><a href="#dom-websocket-bufferedamount">bufferedAmount</a></code>
attribute can also be used to saturate the network without sending
the data at a higher rate than the network can handle, though this
requires more careful monitoring of the value of the attribute over
time.</p>
</div><hr><p>When a <code><a href="#websocket">WebSocket</a></code> object is created, its <dfn id="dom-websocket-binarytype" title="dom-WebSocket-binaryType"><code>binaryType</code></dfn> IDL
attribute must be set to the string "<code title="">blob</code>". On
getting, it must return the last value it was set to. On setting, if
the new value is either the string "<code title="">blob</code>" or
the string "<code title="">arraybuffer</code>", then set the IDL
attribute to this new value. Otherwise, throw a
<code>SYNTAX_ERR</code> exception.<p class="note">This attribute allows authors to control how binary
data is exposed to scripts. By setting the attribute to "<code title="">blob</code>", binary data is returned in <code>Blob</code>
form; by setting it to "<code title="">arraybuffer</code>", it is
returned in <code>ArrayBuffer</code> form. User agents can use this
as a hint for how to handle incoming binary data: if the attribute
is set to "<code title="">blob</code>", it is safe to spool it to
disk, and if it is set to "<code title="">arraybuffer</code>", it is
likely more efficient to keep the data in memory. Naturally, user
agents are encouraged to use more subtle heuristics to decide
whether to keep incoming data in memory or not, e.g. based on how
big the data is or how common it is for a script to change the
attribute at the last minute. This latter aspect is important in
particular because it is quite possible for the attribute to be
changed after the user agent has received the data but before the
user agent as fired the event for it.<p>The <dfn id="dom-websocket-send" title="dom-WebSocket-send"><code>send(<var title="">data</var>)</code></dfn> method transmits data using the
connection. If the <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code> attribute is
<code title="dom-WebSocket-CONNECTING"><a href="#dom-websocket-connecting">CONNECTING</a></code>, it must
raise an <code>INVALID_STATE_ERR</code> exception. Otherwise, the
user agent must run the appropriate set of steps from the following
list:<dl><dt>If the argument is a string</dt>
<dd>
<p>If the <var title="">data</var> argument has any unpaired
surrogates, then raise a <code>SYNTAX_ERR</code> exception. If
<i>the WebSocket connection is established</i>, and the string has
no unpaired surrogates, and <i title="the WebSocket closing
handshake is started">the WebSocket closing handshake has not yet
started</i>, then the user agent must <i>send a WebSocket
Message</i> comprised of <var title="">data</var> using a text
frame opcode; if the data cannot be sent, e.g. because it would
need to be buffered but the buffer is full, the user agent must
<i>close the WebSocket connection</i> <a href="#concept-websocket-close-fail" title="concept-websocket-close-fail">with prejudice</a>. Any
invokation of this method with a string argument that does not
raise an exception must increase the <code title="dom-WebSocket-bufferedAmount"><a href="#dom-websocket-bufferedamount">bufferedAmount</a></code>
attribute by the number of bytes needed to express the argument as
UTF-8. <a href="#refsRFC3629">[RFC3629]</a> <a href="#refsWSP">[WSP]</a></p>
</dd>
<dt>If the argument is a <code>Blob</code> object</dt>
<dd>
<p>If <i>the WebSocket connection is established</i>, and <i title="the WebSocket closing handshake is started">the WebSocket
closing handshake has not yet started</i>, then the user agent
must <i>send a WebSocket Message</i> comprised of <var title="">data</var> using a binary frame opcode; if the data
cannot be sent, e.g. because it would need to be buffered but the
buffer is full, the user agent must <i>close the WebSocket
connection</i> <a href="#concept-websocket-close-fail" title="concept-websocket-close-fail">with
prejudice</a>. The data to be sent is the raw data represented
by the <code>Blob</code> object. Any
invokation of this method with a <code>Blob</code> argument that
does not raise an exception must increase the <code title="dom-WebSocket-bufferedAmount"><a href="#dom-websocket-bufferedamount">bufferedAmount</a></code>
attribute by the size of the <code>Blob</code> object's raw data,
in bytes. <a href="#refsWSP">[WSP]</a> <a href="#refsFILEAPI">[FILEAPI]</a></p>
</dd>
<dt>If the argument is an <code>ArrayBuffer</code> object</dt>
<dd>
<p>If <i>the WebSocket connection is established</i>, and <i title="the WebSocket closing handshake is started">the WebSocket
closing handshake has not yet started</i>, then the user agent
must <i>send a WebSocket Message</i> comprised of <var title="">data</var> using a binary frame opcode; if the data
cannot be sent, e.g. because it would need to be buffered but the
buffer is full, the user agent must <i>close the WebSocket
connection</i> <a href="#concept-websocket-close-fail" title="concept-websocket-close-fail">with
prejudice</a>. The data to be sent is the data stored in the
buffer described by the <code>ArrayBuffer</code> object. Any invokation of this method with an
<code>ArrayBuffer</code> argument that does not raise an exception
must increase the <code title="dom-WebSocket-bufferedAmount"><a href="#dom-websocket-bufferedamount">bufferedAmount</a></code>
attribute by the length of the <code>ArrayBuffer</code> in bytes.
<a href="#refsWSP">[WSP]</a> <a href="#refsTYPEDARRAY">[TYPEDARRAY]</a></p>
</dd>
</dl><hr><p>The following are the <span>event handlers</span> that must be
supported, as IDL attributes, by all objects implementing the
<code><a href="#websocket">WebSocket</a></code> interface:<table><thead><tr><th><span title="event handlers">Event handler</span> <th><span>Event handler event type</span>
<tbody><tr><td><dfn id="handler-websocket-onopen" title="handler-WebSocket-onopen"><code>onopen</code></dfn> <td> <code title="event-open">open</code>
<tr><td><dfn id="handler-websocket-onmessage" title="handler-WebSocket-onmessage"><code>onmessage</code></dfn> <td> <code title="event-message">message</code>
<tr><td><dfn id="handler-websocket-onerror" title="handler-WebSocket-onerror"><code>onerror</code></dfn> <td> <code title="event-error">error</code>
<tr><td><dfn id="handler-websocket-onclose" title="handler-WebSocket-onclose"><code>onclose</code></dfn> <td> <code title="event-close">close</code>
</table><h2 id="feedback-from-the-protocol"><span class="secno">5 </span>Feedback from the protocol</h2><p>When <i>the WebSocket connection is established</i>, the user
agent must <span>queue a task</span> to run these steps:<ol><li><p>Change the <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code> attribute's
value to <code title="dom-WebSocket-OPEN"><a href="#dom-websocket-open">OPEN</a></code> (1).</li>
<li><p>Change the <code title="dom-WebSocket-extensions"><a href="#dom-websocket-extensions">extensions</a></code> attribute's
value to the <i>extensions in use</i>, if is not the null value. <a href="#refsWSP">[WSP]</a></li>
<li><p>Change the <code title="dom-WebSocket-protocol"><a href="#dom-websocket-protocol">protocol</a></code> attribute's value to
the <i>subprotocol in use</i>, if is not the null value. <a href="#refsWSP">[WSP]</a></li>
<li><p>Act as if the user agent had <span title="receives a
set-cookie-string">received a set-cookie-string</span> consisting
of the <i>cookies set during the server's opening handshake</i>,
for the URL <var title="">url</var> given to the <code title="dom-WebSocket"><a href="#dom-websocket">WebSocket()</a></code> constructor. <a href="#refsCOOKIES">[COOKIES]</a> <a href="#refsRFC3629">[RFC3629]</a> <a href="#refsWSP">[WSP]</a></li>
<li><p><span>Fire a simple event</span> named <code title="event-open">open</code> at the <code><a href="#websocket">WebSocket</a></code>
object.</p>
</ol><hr><p>When <i>a WebSocket message has been received</i> with type <var title="">type</var> and data <var title="">data</var>, the user
agent must <span>queue a task</span> to follow these steps: <a href="#refsWSP">[WSP]</a><ol><li>
<p>If the <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code>
attribute's value is not <code title="dom-WebSocket-OPEN"><a href="#dom-websocket-open">OPEN</a></code> (1) or <code title="dom-WebSocket-CLOSING"><a href="#dom-websocket-closing">CLOSING</a></code> (2), then abort these
steps.</p>
</li>
<li>
<p>Let <var title="">event</var> be an event that uses the
<code>MessageEvent</code> interface, with the event name <code title="event-message">message</code>, which does not bubble, is
not cancelable, and has no default action.</p>
</li>
<li><p>Initialize <var title="">event</var>'s <code title="dom-MessageEvent-origin">origin</code> attribute to the
<span title="Unicode serialization of an origin">Unicode
serialization</span> of the <span>origin</span> of the
<span>URL</span> that was passed to the <code><a href="#websocket">WebSocket</a></code>
object's constructor.</li>
<li>
<p>If <var title="">type</var> indicates that the data is Text,
then initialize <var title="">event</var>'s <code title="dom-MessageEvent-data">data</code> attribute to <var title="">data</var>.
<p>If <var title="">type</var> indicates that the data is Binary,
and <code title="dom-WebSocket-binaryType"><a href="#dom-websocket-binarytype">binaryType</a></code> is
set to "<code title="">blob</code>", then initialize <var title="">event</var>'s <code title="dom-MessageEvent-data">data</code> attribute to a new
<code>Blob</code> object that represents <var title="">data</var>
as its raw data. <a href="#refsFILEAPI">[FILEAPI]</a></p>
<p>If <var title="">type</var> indicates that the data is Binary,
and <code title="dom-WebSocket-binaryType"><a href="#dom-websocket-binarytype">binaryType</a></code> is
set to "<code title="">arraybuffer</code>", then initialize <var title="">event</var>'s <code title="dom-MessageEvent-data">data</code> attribute to a new
read-only <code>ArrayBuffer</code> object whose contents are <var title="">data</var>. <a href="#refsTYPEDARRAY">[TYPEDARRAY]</a></p>
</li>
<li>
<p>Dispatch <var title="">event</var> at the
<code><a href="#websocket">WebSocket</a></code> object.</p>
</li>
</ol><p class="note">User agents are encouraged to check if they can
perform the above steps efficiently before they run the task,
picking tasks from other <span title="task queue">task queues</span>
while they prepare the buffers if not. For example, if the <code title="dom-WebSocket-binaryType"><a href="#dom-websocket-binarytype">binaryType</a></code> attribute was set
to "<code title="">blob</code>" when the data arrived, and the user
agent spooled all the data to disk, but just before running the
above <span title="concept-task">task</span> for this particular
message the script switched <code title="dom-WebSocket-binaryType"><a href="#dom-websocket-binarytype">binaryType</a></code> to "<code title="">arraybuffer</code>", the user agent would want to page the
data back to RAM before running this <span title="concept-task">task</span> so as to avoid stalling the main
thread while it created the <code>ArrayBuffer</code> object.<hr><p>When <i>the WebSocket closing handshake is started</i>, the user
agent must <span>queue a task</span> to change the <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code> attribute's value
to <code title="dom-WebSocket-CLOSING"><a href="#dom-websocket-closing">CLOSING</a></code> (2). (If the
<code title="dom-WebSocket-close"><a href="#dom-websocket-close">close()</a></code> method was called,
the <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code>
attribute's value will already be set to <code title="dom-WebSocket-CLOSING"><a href="#dom-websocket-closing">CLOSING</a></code> (2) when this task
runs.) <a href="#refsWSP">[WSP]</a><hr><p id="closeWebSocket">When <i>the WebSocket connection is
closed</i>, possibly <i title="">cleanly</i>, the user agent must
<span>queue a task</span> to run the following substeps:<ol><li><p>Change the <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code> attribute's
value to <code title="dom-WebSocket-CLOSED"><a href="#dom-websocket-closed">CLOSED</a></code>
(3).</li>
<li><p>If the user agent was required to <i>fail the websocket
connection</i> or <i>the WebSocket connection is closed</i> <dfn id="concept-websocket-close-fail" title="concept-websocket-close-fail">with prejudice</dfn>,
<span>fire a simple event</span> named <code title="">error</code>
at the <code><a href="#websocket">WebSocket</a></code> object. <a href="#refsWSP">[WSP]</a></li>
<li><p>Create an event that uses the <code><a href="#closeevent">CloseEvent</a></code>
interface, with the event name <code title="event-close">close</code>, which does not bubble, is not
cancelable, has no default action, whose <code title="dom-CloseEvent-wasClean"><a href="#dom-closeevent-wasclean">wasClean</a></code> attribute is initialized to
true if the connection closed <i title="">cleanly</i> and false
otherwise, whose <code title="dom-CloseEvent-code"><a href="#dom-closeevent-code">code</a></code>
attribute is initialized to <i>the WebSocket connection close code</i>, and
whose <code title="dom-CloseEvent-reason"><a href="#dom-closeevent-reason">reason</a></code> attribute
is initialized to <i>the WebSocket connection close reason</i>
<span>decoded as UTF-8, with error handling</span>, and dispatch
the event at the <code><a href="#websocket">WebSocket</a></code> object. <a href="#refsWSP">[WSP]</a></li>
</ol><p>The <span>task source</span> for all <span title="concept-task">tasks</span> <span title="queue a
task">queued</span> in this section is the <dfn id="websocket-task-source">WebSocket task
source</dfn>.<h3 id="event-definitions"><span class="secno">5.1 </span>Event definitions</h3><pre class="idl">[Constructor(DOMString type, optional <a href="#closeeventinit">CloseEventInit</a> eventInitDict)]
interface <dfn id="closeevent">CloseEvent</dfn> : <span>Event</span> {
readonly attribute boolean <a href="#dom-closeevent-wasclean" title="dom-CloseEvent-wasClean">wasClean</a>;
readonly attribute unsigned short <a href="#dom-closeevent-code" title="dom-CloseEvent-code">code</a>;
readonly attribute DOMString <span title="dom-WebSocket-reason">reason</span>;
};
dictionary <dfn id="closeeventinit">CloseEventInit</dfn> : <span>EventInit</span> {
boolean wasClean;
unsigned short code;
DOMString reason;
};</pre><p>The <dfn id="dom-closeevent-wasclean" title="dom-CloseEvent-wasClean"><code>wasClean</code></dfn>
attribute must return the value it was initialized to. When the
object is created, this attribute must be initialized to false. It
represents whether the connection closed cleanly or not.<p>The <dfn id="dom-closeevent-code" title="dom-CloseEvent-code"><code>code</code></dfn>
attribute must return the value it was initialized to. When the
object is created, this attribute must be initialized to zero. It
represents the WebSocket connection close code provided by the
server.<p>The <dfn id="dom-closeevent-reason" title="dom-CloseEvent-reason"><code>reason</code></dfn>
attribute must return the value it was initialized to. When the
object is created, this attribute must be initialized to empty
string. It represents the WebSocket connection close reason provided
by the server.<h3 id="garbage-collection"><span class="secno">5.2 </span>Garbage collection</h3><p>A <code><a href="#websocket">WebSocket</a></code> object whose <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code> attribute's value
was set to <code title="dom-WebSocket-CONNECTING"><a href="#dom-websocket-connecting">CONNECTING</a></code>
(0) as of the last time the <span>event loop</span> started
executing a <span title="concept-task">task</span> must not be
garbage collected if there are any event listeners registered for
<code title="event-open">open</code> events, <code title="event-message">message</code> events, <code title="event-error">error</code> events, or <code title="event-close">close</code> events.<p>A <code><a href="#websocket">WebSocket</a></code> object whose <code title="dom-WebSocket-readyState"><a href="#dom-websocket-readystate">readyState</a></code> attribute's value
was set to <code title="dom-WebSocket-OPEN"><a href="#dom-websocket-open">OPEN</a></code> (1) or <code title="dom-WebSocket-CLOSING"><a href="#dom-websocket-closing">CLOSING</a></code> (2) as of the last time
the <span>event loop</span> started executing a <span title="concept-task">task</span> must not be garbage collected if
there are any event listeners registered for <code title="event-message">message</code> events, <code title="event-error">error</code>, or <code title="event-close">close</code> events.<p>A <code><a href="#websocket">WebSocket</a></code> object with <i title="the WebSocket
connection is established">an established connection</i> that has
data queued to be transmitted to the network must not be garbage
collected. <a href="#refsWSP">[WSP]</a><p>If a <code><a href="#websocket">WebSocket</a></code> object is garbage collected while its
connection is still open, the user agent must <i>start the
WebSocket closing handshake</i>, with no status code for the Close message. <a href="#refsWSP">[WSP]</a><hr><p>If a user agent is to <dfn id="make-disappear">make disappear</dfn> a
<code><a href="#websocket">WebSocket</a></code> object (this happens when a
<code>Document</code> object goes away), the user agent must follow
the first appropriate set of steps from the following list:<dl class="switch"><dt>If the WebSocket connection is not yet <i title="the WebSocket
connection is established">established</i> <a href="#refsWSP">[WSP]</a></dt>
<dd>
<p><i>Fail the WebSocket connection</i>. <a href="#refsWSP">[WSP]</a></p>
</dd>
<dt>If the WebSocket closing handshake has not yet been <i title="the WebSocket closing handshake is started">started</i>
<a href="#refsWSP">[WSP]</a></dt>
<dd>
<p><i>Start the WebSocket closing handshake</i>, with the
status code<!--CLOSE CODE--> to use in the WebSocket Close message
being 1001. <a href="#refsWSP">[WSP]</a></p>
</dd>
<dt>Otherwise</dt>
<dd>
<p>Do nothing.</p>
</dd>
</dl><h2 class="no-num" id="references">References</h2><p>All references are normative unless marked "Non-normative".</p><dl><dt id="refsCOOKIES">[COOKIES]</dt>
<dd><cite><a href="http://tools.ietf.org/html/rfc6265">HTTP State Management Mechanism</a></cite>, A. Barth. IETF.</dd>
<dt id="refsDOMCORE">[DOMCORE]</dt>
<dd><cite><a href="http://dvcs.w3.org/hg/domcore/raw-file/tip/Overview.html">Web DOM Core</a></cite>, A. van Kesteren. W3C.</dd>
<dt id="refsFILEAPI">[FILEAPI]</dt>
<dd><cite><a href="http://dev.w3.org/2006/webapi/FileUpload/publish/FileAPI.html">File
API</a></cite>, A. Ranganathan. W3C.</dd>
<dt id="refsHTML">[HTML]</dt>
<dd><cite><a href="http://www.whatwg.org/specs/web-apps/current-work/">HTML</a></cite>,
I. Hickson. WHATWG.</dd>
<dt id="refsRFC2119">[RFC2119]</dt>
<dd><cite><a href="http://tools.ietf.org/html/rfc2119">Key words for use in
RFCs to Indicate Requirement Levels</a></cite>, S. Bradner. IETF.</dd>
<dt id="refsRFC3629">[RFC3629]</dt>
<dd><cite><a href="http://tools.ietf.org/html/rfc3629">UTF-8, a
transformation format of ISO 10646</a></cite>, F. Yergeau. IETF.</dd>
<dt id="refsTYPEDARRAY">[TYPEDARRAY]</dt>
<dd><cite><a href="http://www.khronos.org/registry/typedarray/specs/latest/">Typed Array Specification</a></cite>, D. Herman, K. Russell. Khronos.</dd>
<dt id="refsWEBIDL">[WEBIDL]</dt>
<dd><cite><a href="http://dev.w3.org/2006/webapi/WebIDL/">Web
IDL</a></cite>, C. McCormack. W3C.</dd>
<dt id="refsWSP">[WSP]</dt>
<dd><cite><a href="http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol">The
WebSocket protocol</a></cite>, I. Fette. IETF.</dd>
</dl><h2 class="no-num" id="acknowledgements">Acknowledgements</h2><p>For a full list of acknowledgements, please see the HTML
specification. <a href="#refsHTML">[HTML]</a>
Received on Wednesday, 28 September 2011 14:06:44 UTC