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<title>Sets whether this cursor will wait for a while for a tailable cursor to return more data</title>
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<h1 class="refname">MongoCursor::awaitData</h1>
<p class="verinfo">(PECL mongo >=1.2.11)</p><p class="refpurpose"><span class="refname">MongoCursor::awaitData</span> — <span class="dc-title">Sets whether this cursor will wait for a while for a tailable cursor to return more data</span></p>
</div>
<div class="refsect1 description" id="refsect1-mongocursor.awaitdata-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="modifier">public</span> <span class="type"><a href="class.mongocursor.html" class="type MongoCursor">MongoCursor</a></span> <span class="methodname"><strong>MongoCursor::awaitData</strong></span>
([ <span class="methodparam"><span class="type">bool</span> <code class="parameter">$wait</code><span class="initializer"> = true</span></span>
] )</div>
<p class="para rdfs-comment">
This method is to be used with tailable cursors. If we are at the end of
the data, block for a while rather than returning no data. After a timeout
period, we do return as normal.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-mongocursor.awaitdata-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term">
<em><code class="parameter">wait</code></em>
</span>
<dd>
<p class="para">
If the cursor should wait for more data to become available.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-mongocursor.awaitdata-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns this cursor.
</p>
</div>
<div class="refsect1 errors" id="refsect1-mongocursor.awaitdata-errors">
<h3 class="title">Errors/Exceptions</h3>
<p class="para">
Throws <a href="class.mongocursorexception.html" class="classname">MongoCursorException</a> if this cursor has started iterating.
</p>
</div>
<div class="refsect1 examples" id="refsect1-mongocursor.awaitdata-examples">
<h3 class="title">Examples</h3>
<div class="example" id="example-1476">
<p><strong>Example #1 <span class="function"><strong>MongoCursor::awaitData()</strong></span> example</strong></p>
<div class="example-contents"><p>
In this example we tail the "oplog" and instead of sleeping during every
iteration, we set the <span class="function"><strong>MongoCursor::awaitData()</strong></span> option.
<span class="function"><a href="mongocursor.hasnext.html" class="function">MongoCursor::hasNext()</a></span> will now block until there is
more data available.
</p></div>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$m </span><span style="color: #007700">= new </span><span style="color: #0000BB">MongoClient</span><span style="color: #007700">( </span><span style="color: #DD0000">'mongodb://localhost:13000'</span><span style="color: #007700">, array( </span><span style="color: #DD0000">'replSet' </span><span style="color: #007700">=> </span><span style="color: #DD0000">'seta' </span><span style="color: #007700">) );<br /></span><span style="color: #0000BB">$c </span><span style="color: #007700">= </span><span style="color: #0000BB">$m</span><span style="color: #007700">-></span><span style="color: #0000BB">local</span><span style="color: #007700">-></span><span style="color: #0000BB">selectCollection</span><span style="color: #007700">( </span><span style="color: #DD0000">'oplog.rs' </span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$cursor </span><span style="color: #007700">= </span><span style="color: #0000BB">$c</span><span style="color: #007700">-></span><span style="color: #0000BB">find</span><span style="color: #007700">( array( </span><span style="color: #DD0000">'ns' </span><span style="color: #007700">=> </span><span style="color: #DD0000">'demo.article'</span><span style="color: #007700">, </span><span style="color: #DD0000">'op' </span><span style="color: #007700">=> </span><span style="color: #DD0000">'i' </span><span style="color: #007700">) );<br /></span><span style="color: #0000BB">$cursor</span><span style="color: #007700">-></span><span style="color: #0000BB">tailable</span><span style="color: #007700">( </span><span style="color: #0000BB">true </span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$cursor</span><span style="color: #007700">-></span><span style="color: #0000BB">awaitData</span><span style="color: #007700">( </span><span style="color: #0000BB">true </span><span style="color: #007700">);<br /><br />while (</span><span style="color: #0000BB">true</span><span style="color: #007700">) {<br /> if (!</span><span style="color: #0000BB">$cursor</span><span style="color: #007700">-></span><span style="color: #0000BB">hasNext</span><span style="color: #007700">()) {<br /> </span><span style="color: #FF8000">// we've read all the results, exit<br /> </span><span style="color: #007700">if (</span><span style="color: #0000BB">$cursor</span><span style="color: #007700">-></span><span style="color: #0000BB">dead</span><span style="color: #007700">()) {<br /> break;<br /> }<br /> } else {<br /> </span><span style="color: #0000BB">var_dump</span><span style="color: #007700">( </span><span style="color: #0000BB">$cursor</span><span style="color: #007700">-></span><span style="color: #0000BB">getNext</span><span style="color: #007700">() );<br /> }<br />}<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</div>
<div class="refsect1 seealso" id="refsect1-mongocursor.awaitdata-seealso">
<h3 class="title">See Also</h3>
<p class="para">
MongoDB core docs on <a href="http://docs.mongodb.org/manual/tutorial/create-tailable-cursor/" class="link external">» tailable cursors</a>.
</p>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="mongocursor.tailable.html" class="function" rel="rdfs-seeAlso">MongoCursor::tailable()</a> - Sets whether this cursor will be left open after fetching the last results</span></li>
</ul>
</p>
</div>
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