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<h1>nng_msg_header(3)</h1>
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<h2 id="_name">NAME</h2>
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<p>nng_msg_header - return message header</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;nng/nng.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">nng_msg_header</span><span class="tok-p">(</span><span class="tok-n">nng_msg</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_header()</code> function returns a pointer to the start of the header
content of the message <em>msg</em>.</p>
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The message header contains protocol-specific header content.  Most
applications should not need to access this content, but it is available
for raw mode sockets (set with the
<a href="nng_options.5.html"><code>NNG_OPT_RAW</code></a> option.)
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The value returned by this is invalidated by a call to any of the
functions that modify the message or the header content.
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<h2 id="_return_values">RETURN VALUES</h2>
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<p>Pointer to start of message header.</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_alloc.3.html">nng_msg_alloc(3)</a>,
<a href="nng_msg_body.3.html">nng_msg_body(3)</a>,
<a href="nng_msg_free.3.html">nng_msg_free(3)</a>,
<a href="nng_msg_header_append.3.html">nng_msg_header_append(3)</a>,
<a href="nng_msg_header_chop.3.html">nng_msg_header_chop(3)</a>,
<a href="nng_msg_header_insert.3.html">nng_msg_header_insert(3)</a>
<a href="nng_msg_header_len.3.html">nng_msg_header_len(3)</a>,
<a href="nng_msg_header_trim.3.html">nng_msg_header_trim(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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