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           <div id="toc">
             <h2>Table of Contents</h2>
             <ul>
 <li><a href="#events_events">Events</a><ul>
 <li><a href="#events_class_events_eventemitter">Class: events.EventEmitter</a><ul>
 <li><a href="#events_emitter_addlistener_event_listener">emitter.addListener(event, listener)</a></li>
 <li><a href="#events_emitter_on_event_listener">emitter.on(event, listener)</a></li>
 <li><a href="#events_emitter_once_event_listener">emitter.once(event, listener)</a></li>
 <li><a href="#events_emitter_removelistener_event_listener">emitter.removeListener(event, listener)</a></li>
 <li><a href="#events_emitter_removealllisteners_event">emitter.removeAllListeners([event])</a></li>
 <li><a href="#events_emitter_setmaxlisteners_n">emitter.setMaxListeners(n)</a></li>
 <li><a href="#events_emitter_listeners_event">emitter.listeners(event)</a></li>
 <li><a href="#events_emitter_emit_event_arg1_arg2">emitter.emit(event, [arg1], [arg2], [...])</a></li>
 <li><a href="#events_class_method_eventemitter_listenercount_emitter_event">Class Method: EventEmitter.listenerCount(emitter, event)</a></li>
 <li><a href="#events_event_newlistener">Event: &#39;newListener&#39;</a></li>
 <li><a href="#events_event_removelistener">Event: &#39;removeListener&#39;</a></li>
 </ul>
 </li>
 </ul>
 </li>
 </ul>

           </div>

           <div id="apicontent">
             <h1>Events<span><a class="mark" href="#events_events" id="events_events">#</a></span></h1>
 <pre class="api_stability_4">Stability: 4 - API Frozen</pre><!--type=module-->

 <p>Many objects in Node emit events: a <code>net.Server</code> emits an event each time
 a peer connects to it, a <code>fs.readStream</code> emits an event when the file is
 opened. All objects which emit events are instances of <code>events.EventEmitter</code>.
 You can access this module by doing: <code>require(&quot;events&quot;);</code>

 </p>
 <p>Typically, event names are represented by a camel-cased string, however,
 there aren&#39;t any strict restrictions on that, as any string will be accepted.

 </p>
 <p>Functions can then be attached to objects, to be executed when an event
 is emitted. These functions are called <em>listeners</em>. Inside a listener
 function, <code>this</code> refers to the <code>EventEmitter</code> that the listener was
 attached to.


 </p>
 <h2>Class: events.EventEmitter<span><a class="mark" href="#events_class_events_eventemitter" id="events_class_events_eventemitter">#</a></span></h2>
 <p>To access the EventEmitter class, <code>require(&#39;events&#39;).EventEmitter</code>.

 </p>
 <p>When an <code>EventEmitter</code> instance experiences an error, the typical action is
 to emit an <code>&#39;error&#39;</code> event.  Error events are treated as a special case in node.
 If there is no listener for it, then the default action is to print a stack
 trace and exit the program.

 </p>
 <p>All EventEmitters emit the event <code>&#39;newListener&#39;</code> when new listeners are
 added and <code>&#39;removeListener&#39;</code> when a listener is removed.

 </p>
 <h3>emitter.addListener(event, listener)<span><a class="mark" href="#events_emitter_addlistener_event_listener" id="events_emitter_addlistener_event_listener">#</a></span></h3>
 <h3>emitter.on(event, listener)<span><a class="mark" href="#events_emitter_on_event_listener" id="events_emitter_on_event_listener">#</a></span></h3>
 <p>Adds a listener to the end of the listeners array for the specified event.

 </p>
 <pre><code>server.on(&#39;connection&#39;, function (stream) {
   console.log(&#39;someone connected!&#39;);
 });</code></pre>
 <p>Returns emitter, so calls can be chained.

 </p>
 <h3>emitter.once(event, listener)<span><a class="mark" href="#events_emitter_once_event_listener" id="events_emitter_once_event_listener">#</a></span></h3>
 <p>Adds a <strong>one time</strong> listener for the event. This listener is
 invoked only the next time the event is fired, after which
 it is removed.

 </p>
 <pre><code>server.once(&#39;connection&#39;, function (stream) {
   console.log(&#39;Ah, we have our first user!&#39;);
 });</code></pre>
 <p>Returns emitter, so calls can be chained.

 </p>
 <h3>emitter.removeListener(event, listener)<span><a class="mark" href="#events_emitter_removelistener_event_listener" id="events_emitter_removelistener_event_listener">#</a></span></h3>
 <p>Remove a listener from the listener array for the specified event.
 <strong>Caution</strong>: changes array indices in the listener array behind the listener.

 </p>
 <pre><code>var callback = function(stream) {
   console.log(&#39;someone connected!&#39;);
 };
 server.on(&#39;connection&#39;, callback);
 // ...
 server.removeListener(&#39;connection&#39;, callback);</code></pre>
 <p>Returns emitter, so calls can be chained.

 </p>
 <h3>emitter.removeAllListeners([event])<span><a class="mark" href="#events_emitter_removealllisteners_event" id="events_emitter_removealllisteners_event">#</a></span></h3>
 <p>Removes all listeners, or those of the specified event.

 </p>
 <p>Returns emitter, so calls can be chained.

 </p>
 <h3>emitter.setMaxListeners(n)<span><a class="mark" href="#events_emitter_setmaxlisteners_n" id="events_emitter_setmaxlisteners_n">#</a></span></h3>
 <p>By default EventEmitters will print a warning if more than 10 listeners are
 added for a particular event. This is a useful default which helps finding memory leaks.
 Obviously not all Emitters should be limited to 10. This function allows
 that to be increased. Set to zero for unlimited.


 </p>
 <h3>emitter.listeners(event)<span><a class="mark" href="#events_emitter_listeners_event" id="events_emitter_listeners_event">#</a></span></h3>
 <p>Returns an array of listeners for the specified event.

 </p>
 <pre><code>server.on(&#39;connection&#39;, function (stream) {
   console.log(&#39;someone connected!&#39;);
 });
 console.log(util.inspect(server.listeners(&#39;connection&#39;))); // [ [Function] ]</code></pre>
 <h3>emitter.emit(event, [arg1], [arg2], [...])<span><a class="mark" href="#events_emitter_emit_event_arg1_arg2" id="events_emitter_emit_event_arg1_arg2">#</a></span></h3>
 <p>Execute each of the listeners in order with the supplied arguments.

 </p>
 <p>Returns <code>true</code> if event had listeners, <code>false</code> otherwise.


 </p>
 <h3>Class Method: EventEmitter.listenerCount(emitter, event)<span><a class="mark" href="#events_class_method_eventemitter_listenercount_emitter_event" id="events_class_method_eventemitter_listenercount_emitter_event">#</a></span></h3>
 <p>Return the number of listeners for a given event.


 </p>
 <h3>Event: &#39;newListener&#39;<span><a class="mark" href="#events_event_newlistener" id="events_event_newlistener">#</a></span></h3>
 <div class="signature"><ul>
 <li><code>event</code> <span class="type">String</span> The event name</li>
 <li><code>listener</code> <span class="type">Function</span> The event handler function</li>
 </div></ul>
 <p>This event is emitted any time someone adds a new listener.  It is unspecified
 if <code>listener</code> is in the list returned by <code>emitter.listeners(event)</code>.


 </p>
 <h3>Event: &#39;removeListener&#39;<span><a class="mark" href="#events_event_removelistener" id="events_event_removelistener">#</a></span></h3>
 <div class="signature"><ul>
 <li><code>event</code> <span class="type">String</span> The event name</li>
 <li><code>listener</code> <span class="type">Function</span> The event handler function</li>
 </div></ul>
 <p>This event is emitted any time someone removes a listener.  It is unspecified
 if <code>listener</code> is in the list returned by <code>emitter.listeners(event)</code>.
 </p>

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	<div id="toc">
	<h2>Table of Contents</h2>
	<ul>
	<li><a href="#events_events">Events</a><ul>
	<li><a href="#events_class_events_eventemitter">Class: events.EventEmitter</a><ul>
	<li><a href="#events_emitter_addlistener_event_listener">emitter.addListener(event, listener)</a></li>
	<li><a href="#events_emitter_on_event_listener">emitter.on(event, listener)</a></li>
	<li><a href="#events_emitter_once_event_listener">emitter.once(event, listener)</a></li>
	<li><a href="#events_emitter_removelistener_event_listener">emitter.removeListener(event, listener)</a></li>
	<li><a href="#events_emitter_removealllisteners_event">emitter.removeAllListeners([event])</a></li>
	<li><a href="#events_emitter_setmaxlisteners_n">emitter.setMaxListeners(n)</a></li>
	<li><a href="#events_emitter_listeners_event">emitter.listeners(event)</a></li>
	<li><a href="#events_emitter_emit_event_arg1_arg2">emitter.emit(event, [arg1], [arg2], [...])</a></li>
	<li><a href="#events_class_method_eventemitter_listenercount_emitter_event">Class Method: EventEmitter.listenerCount(emitter, event)</a></li>
	<li><a href="#events_event_newlistener">Event: 'newListener'</a></li>
	<li><a href="#events_event_removelistener">Event: 'removeListener'</a></li>
	</ul>
	</li>
	</ul>
	</li>
	</ul>

	</div>

	<div id="apicontent">
	<h1>Events<span><a class="mark" href="#events_events" id="events_events">#</a></span></h1>
	<pre class="api_stability_4">Stability: 4 - API Frozen</pre><!--type=module-->

	<p>Many objects in Node emit events: a <code>net.Server</code> emits an event each time
	a peer connects to it, a <code>fs.readStream</code> emits an event when the file is
	opened. All objects which emit events are instances of <code>events.EventEmitter</code>.
	You can access this module by doing: <code>require("events");</code>

	</p>
	<p>Typically, event names are represented by a camel-cased string, however,
	there aren't any strict restrictions on that, as any string will be accepted.

	</p>
	<p>Functions can then be attached to objects, to be executed when an event
	is emitted. These functions are called <em>listeners</em>. Inside a listener
	function, <code>this</code> refers to the <code>EventEmitter</code> that the listener was
	attached to.


	</p>
	<h2>Class: events.EventEmitter<span><a class="mark" href="#events_class_events_eventemitter" id="events_class_events_eventemitter">#</a></span></h2>
	<p>To access the EventEmitter class, <code>require('events').EventEmitter</code>.

	</p>
	<p>When an <code>EventEmitter</code> instance experiences an error, the typical action is
	to emit an <code>'error'</code> event. Error events are treated as a special case in node.
	If there is no listener for it, then the default action is to print a stack
	trace and exit the program.

	</p>
	<p>All EventEmitters emit the event <code>'newListener'</code> when new listeners are
	added and <code>'removeListener'</code> when a listener is removed.

	</p>
	<h3>emitter.addListener(event, listener)<span><a class="mark" href="#events_emitter_addlistener_event_listener" id="events_emitter_addlistener_event_listener">#</a></span></h3>
	<h3>emitter.on(event, listener)<span><a class="mark" href="#events_emitter_on_event_listener" id="events_emitter_on_event_listener">#</a></span></h3>
	<p>Adds a listener to the end of the listeners array for the specified event.

	</p>
	<pre><code>server.on('connection', function (stream) {
	console.log('someone connected!');
	});</code></pre>
	<p>Returns emitter, so calls can be chained.

	</p>
	<h3>emitter.once(event, listener)<span><a class="mark" href="#events_emitter_once_event_listener" id="events_emitter_once_event_listener">#</a></span></h3>
	<p>Adds a <strong>one time</strong> listener for the event. This listener is
	invoked only the next time the event is fired, after which
	it is removed.

	</p>
	<pre><code>server.once('connection', function (stream) {
	console.log('Ah, we have our first user!');
	});</code></pre>
	<p>Returns emitter, so calls can be chained.

	</p>
	<h3>emitter.removeListener(event, listener)<span><a class="mark" href="#events_emitter_removelistener_event_listener" id="events_emitter_removelistener_event_listener">#</a></span></h3>
	<p>Remove a listener from the listener array for the specified event.
	<strong>Caution</strong>: changes array indices in the listener array behind the listener.

	</p>
	<pre><code>var callback = function(stream) {
	console.log('someone connected!');
	};
	server.on('connection', callback);
	// ...
	server.removeListener('connection', callback);</code></pre>
	<p>Returns emitter, so calls can be chained.

	</p>
	<h3>emitter.removeAllListeners([event])<span><a class="mark" href="#events_emitter_removealllisteners_event" id="events_emitter_removealllisteners_event">#</a></span></h3>
	<p>Removes all listeners, or those of the specified event.

	</p>
	<p>Returns emitter, so calls can be chained.

	</p>
	<h3>emitter.setMaxListeners(n)<span><a class="mark" href="#events_emitter_setmaxlisteners_n" id="events_emitter_setmaxlisteners_n">#</a></span></h3>
	<p>By default EventEmitters will print a warning if more than 10 listeners are
	added for a particular event. This is a useful default which helps finding memory leaks.
	Obviously not all Emitters should be limited to 10. This function allows
	that to be increased. Set to zero for unlimited.


	</p>
	<h3>emitter.listeners(event)<span><a class="mark" href="#events_emitter_listeners_event" id="events_emitter_listeners_event">#</a></span></h3>
	<p>Returns an array of listeners for the specified event.

	</p>
	<pre><code>server.on('connection', function (stream) {
	console.log('someone connected!');
	});
	console.log(util.inspect(server.listeners('connection'))); // [ [Function] ]</code></pre>
	<h3>emitter.emit(event, [arg1], [arg2], [...])<span><a class="mark" href="#events_emitter_emit_event_arg1_arg2" id="events_emitter_emit_event_arg1_arg2">#</a></span></h3>
	<p>Execute each of the listeners in order with the supplied arguments.

	</p>
	<p>Returns <code>true</code> if event had listeners, <code>false</code> otherwise.


	</p>
	<h3>Class Method: EventEmitter.listenerCount(emitter, event)<span><a class="mark" href="#events_class_method_eventemitter_listenercount_emitter_event" id="events_class_method_eventemitter_listenercount_emitter_event">#</a></span></h3>
	<p>Return the number of listeners for a given event.


	</p>
	<h3>Event: 'newListener'<span><a class="mark" href="#events_event_newlistener" id="events_event_newlistener">#</a></span></h3>
	<div class="signature"><ul>
	<li><code>event</code> <span class="type">String</span> The event name</li>
	<li><code>listener</code> <span class="type">Function</span> The event handler function</li>
	</div></ul>
	<p>This event is emitted any time someone adds a new listener. It is unspecified
	if <code>listener</code> is in the list returned by <code>emitter.listeners(event)</code>.


	</p>
	<h3>Event: 'removeListener'<span><a class="mark" href="#events_event_removelistener" id="events_event_removelistener">#</a></span></h3>
	<div class="signature"><ul>
	<li><code>event</code> <span class="type">String</span> The event name</li>
	<li><code>listener</code> <span class="type">Function</span> The event handler function</li>
	</div></ul>
	<p>This event is emitted any time someone removes a listener. It is unspecified
	if <code>listener</code> is in the list returned by <code>emitter.listeners(event)</code>.
	</p>

	</div>
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