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version: tip
layout: manpage_v2
title: nng_msg_capacity(3)
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<h1>nng_msg_capacity(3)</h1>
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<h2 id="_name">NAME</h2>
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<p>nng_msg_capacity - return message body length</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-kt">size_t</span><span class="tok-w"> </span><span class="tok-nf">nng_msg_capacity</span><span class="tok-p">(</span><span class="tok-n">nng_msg</span><span class="tok-w"> </span><span class="tok-o">*</span><span class="tok-n">msg</span><span class="tok-p">);</span></code></pre>
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<h2 id="_description">DESCRIPTION</h2>
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<p>The <code>nng_msg_capacity()</code> returns the storage allocated for the body of message <em>msg</em>.
The capacity includes the current contents of the message and free space after it.
The message body may grow to capacity without performing any further allocations.</p>
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<h2 id="_return_values">RETURN VALUES</h2>
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<p>Allocated capacity for message body.</p>
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<h2 id="_errors">ERRORS</h2>
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<p>None.</p>
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<h2 id="_see_also">SEE ALSO</h2>
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<p><a href="nng_msg_reserve.3.html">nng_msg_reserve(3)</a>,
<a href="nng_msg_alloc.3.html">nng_msg_alloc(3)</a>,
<a href="nng_msg_body.3.html">nng_msg_body(3)</a>,
<a href="nng_msg.5.html">nng_msg(5)</a>,
<a href="nng.7.html">nng(7)</a></p>
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