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version: tip
layout: manpage_v2
title: nng_duration(5)
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<h1>nng_duration(5)</h1>
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<h2 id="_name">NAME</h2>
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<p>nng_duration - relative time in milliseconds</p>
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<h2 id="_synopsis">SYNOPSIS</h2>
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<pre class="pygments highlight"><code data-lang="c"><span></span><span class="tok-cp">#include</span><span class="tok-w"> </span><span class="tok-cpf">&lt;nng/nng.h&gt;</span>

<span class="tok-k">typedef</span><span class="tok-w"> </span><span class="tok-kt">int32_t</span><span class="tok-w"> </span><span class="tok-n">nng_duration</span><span class="tok-p">;</span>

<span class="tok-cp">#define NNG_DURATION_INFINITE (-1)</span>
<span class="tok-cp">#define NNG_DURATION_DEFAULT  (-2)</span>
<span class="tok-cp">#define NNG_DURATION_ZERO     (0)</span></code></pre>
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<h2 id="_description">DESCRIPTION</h2>
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<p>An <code>nng_duration</code> is a relative time, measured in
milliseconds.
This type is most often used in conjunction with timers and timeouts.</p>
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<p>A couple of special values have been set aside, and carry special meanings.</p>
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<dt class="hdlist1"><code>NNG_DURATION_DEFAULT</code></dt>
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<p>Indicates a context-specific default value should be used.</p>
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<dt class="hdlist1"><code>NNG_DURATION_INFINITE</code></dt>
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<p>Effectively an infinite duration; used most often to disable timeouts.</p>
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<dt class="hdlist1"><code>NNG_DURATION_ZERO</code></dt>
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<p>Zero length duration; used to perform a single polling operation.</p>
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<h2 id="_see_also">SEE ALSO</h2>
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<p><a href="nng_options.5.html">nng_options(5)</a>,
<a href="nng.7.html">nng(7)</a></p>
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