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<h1>nn_reallocmsg(3compat)</h1>
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<h2 id="_name">NAME</h2>
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<p>nn_reallocmsg - reallocate message (compatible API)</p>
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<h2 id="_synopsis">SYNOPSIS</h2>
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<pre class="pygments highlight"><code data-lang="c"><span class="tok-cp">#include</span> <span class="tok-cpf">&lt;nanomsg/nn.h&gt;</span><span class="tok-cp">
</span><span class="tok-cp"></span>
<span class="tok-kt">void</span> <span class="tok-o">*</span><span class="tok-nf">nn_reallocmsg</span><span class="tok-p">(</span><span class="tok-kt">void</span> <span class="tok-o">*</span><span class="tok-n">old</span><span class="tok-p">,</span> <span class="tok-n">size_t</span> <span class="tok-n">size</span><span class="tok-p">);</span></code></pre>
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<h2 id="_description">DESCRIPTION</h2>
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<p>The <code>nn_reallocmsg()</code> reallocates the message <em>old</em>, making it of size <em>size</em>.</p>
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This function is provided for API
<a href="nng_compat.3compat.html">compatibility</a> with legacy <em>libnanomsg</em>.
Consider using the relevant <a href="libnng.3.html">modern API</a> instead.
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<p>On success, the contents of <em>old</em> are copied into the new message
(truncating if appropriate), then <em>old</em> is deallocated, and a pointer
to the new message payload is returned.</p>
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<p>On failure, the <em>old</em> message is unchanged, and the value <code>NULL</code> is returned
to the caller.</p>
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<h2 id="_return_values">RETURN VALUES</h2>
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<p>This function returns a pointer to message buffer space, or <code>NULL</code>
on failure.</p>
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<h2 id="_errors">ERRORS</h2>
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<code>ENOMEM</code>
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<p>Insufficient memory is available.</p>
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<code>EINVAL</code>
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<p>An invalid <em>size</em> was specified.</p>
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<code>ETERM</code>
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<p>The library is shutting down.</p>
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<h2 id="_see_also">SEE ALSO</h2>
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<p><a href="nn_allocmsg.3compat.html">nn_allocmsg(3compat)</a>,
<a href="nn_freemsg.3compat.html">nn_freemsg(3compat)</a>,
<a href="nn_errno.3compat.html">nn_errno(3compat)</a>,
<a href="nng_compat.3compat.html">nng_compat(3compat)</a>,
<a href="nng.7.html">nng(7)</a></p>
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