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            <h1>IO::Poll</h1>


  <!--    -->
<ul><li><a href="#NAME">NAME</a><li><a href="#SYNOPSIS">SYNOPSIS</a><li><a href="#DESCRIPTION">DESCRIPTION</a><li><a href="#METHODS">METHODS</a><li><a href="#SEE-ALSO">SEE ALSO</a><li><a href="#AUTHOR">AUTHOR</a><li><a href="#COPYRIGHT">COPYRIGHT</a></ul><a name="NAME"></a><h1>NAME</h1>
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<p>IO::Poll - Object interface to system poll call</p>
<a name="SYNOPSIS"></a><h1>SYNOPSIS</h1>
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<pre class="verbatim"><ol><li>    <a class="l_k" href="../functions/use.html">use</a> <span class="w">IO::Poll</span> <span class="q">qw(POLLRDNORM POLLWRNORM POLLIN POLLHUP)</span><span class="sc">;</span></li><li></li><li>    <span class="i">$poll</span> = <span class="w">IO::Poll</span><span class="w">-&gt;new</span><span class="s">(</span><span class="s">)</span><span class="sc">;</span></li><li></li><li>    <span class="i">$poll</span><span class="i">-&gt;mask</span><span class="s">(</span><span class="i">$input_handle</span> <span class="cm">=&gt;</span> <span class="w">POLLIN</span><span class="s">)</span><span class="sc">;</span></li><li>    <span class="i">$poll</span><span class="i">-&gt;mask</span><span class="s">(</span><span class="i">$output_handle</span> <span class="cm">=&gt;</span> <span class="w">POLLOUT</span><span class="s">)</span><span class="sc">;</span></li><li></li><li>    <span class="i">$poll</span><span class="i">-&gt;poll</span><span class="s">(</span><span class="i">$timeout</span><span class="s">)</span><span class="sc">;</span></li><li></li><li>    <span class="i">$ev</span> = <span class="i">$poll</span><span class="i">-&gt;events</span><span class="s">(</span><span class="i">$input</span><span class="s">)</span><span class="sc">;</span></li></ol></pre><a name="DESCRIPTION"></a><h1>DESCRIPTION</h1>
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<p><code class="inline"><span class="w">IO::Poll</span></code>
 is a simple interface to the system level poll routine.</p>
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<a name="METHODS"></a><h1>METHODS</h1>
<ul>
<li><a name="mask-(-IO-%5b%2c-EVENT_MASK-%5d-)"></a><b>mask ( IO [, EVENT_MASK ] )</b>
<p>If EVENT_MASK is given, then, if EVENT_MASK is non-zero, IO is added to the
list of file descriptors and the next call to poll will check for
any event specified in EVENT_MASK. If EVENT_MASK is zero then IO will be
removed from the list of file descriptors.</p>
<p>If EVENT_MASK is not given then the return value will be the current
event mask value for IO.</p>
</li>
<li><a name="poll-(-%5b-TIMEOUT-%5d-)"></a><b>poll ( [ TIMEOUT ] )</b>
<p>Call the system level poll routine. If TIMEOUT is not specified then the
call will block. Returns the number of handles which had events
happen, or -1 on error.</p>
</li>
<li><a name="events-(-IO-)"></a><b>events ( IO )</b>
<p>Returns the event mask which represents the events that happened on IO
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during the last call to <code class="inline"><span class="w">poll</span></code>
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.</p>
</li>
<li><a name="remove-(-IO-)"></a><b>remove ( IO )</b>
<p>Remove IO from the list of file descriptors for the next poll.</p>
</li>
<li><a name="handles(-%5b-EVENT_MASK-%5d-)"></a><b>handles( [ EVENT_MASK ] )</b>
<p>Returns a list of handles. If EVENT_MASK is not given then a list of all
handles known will be returned. If EVENT_MASK is given then a list
of handles will be returned which had one of the events specified by
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EVENT_MASK happen during the last call ti <code class="inline"><span class="w">poll</span></code>
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</p>
</li>
</ul>
<a name="SEE-ALSO"></a><h1>SEE ALSO</h1>
<p><i>poll(2)</i>, <a href="../IO/Handle.html">IO::Handle</a>, <a href="../IO/Select.html">IO::Select</a></p>
<a name="AUTHOR"></a><h1>AUTHOR</h1>
<p>Graham Barr. Currently maintained by the Perl Porters.  Please report all
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bugs to &lt;perlbug@perl.org&gt;.</p>
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<a name="COPYRIGHT"></a><h1>COPYRIGHT</h1>
<p>Copyright (c) 1997-8 Graham Barr &lt;gbarr@pobox.com&gt;. All rights reserved.
This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.</p>
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