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---
version: tip
layout: manpage_v2
title: nng_stats_get(3)
---
<h1>nng_stats_get(3)</h1>
<div class="sect1">
<h2 id="_name">NAME</h2>
<div class="sectionbody">
<div class="paragraph">
<p>nng_stats_get - get statistics snapshot</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_synopsis">SYNOPSIS</h2>
<div class="sectionbody">
<div class="listingblock">
<div class="content">
<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"><nng/nng.h></span>
<span class="tok-k">typedef</span><span class="tok-w"> </span><span class="tok-k">struct</span><span class="tok-w"> </span><span class="tok-nc">nng_stat</span><span class="tok-w"> </span><span class="tok-n">nng_stat</span><span class="tok-p">;</span>
<span class="tok-kt">int</span><span class="tok-w"> </span><span class="tok-n">nng_stats_get</span><span class="tok-p">(</span><span class="tok-n">nng_stat</span><span class="tok-w"> </span><span class="tok-o">**</span><span class="tok-n">statsp</span><span class="tok-p">)</span></code></pre>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_description">DESCRIPTION</h2>
<div class="sectionbody">
<div class="paragraph">
<p>The <code>nng_stat_get()</code> function attempts to obtain a snapshot of all the
various diagnostic statistics that are present in the system.</p>
</div>
<div class="admonitionblock note">
<table>
<tr>
<td class="icon">
<i class="fa icon-note" title="Note"></i>
</td>
<td class="content">
The process of collecting statistics is designed to have minimal
impact on the system, but there is still some impact.
</td>
</tr>
</table>
</div>
<div class="paragraph">
<p>The statistics are organized as a tree, rooted with a parent
statistic of type <code>NNG_STAT_SCOPE</code> that carries no value, and which
has an empty name.
This parent statistic is returned through the <em>statsp</em> pointer.</p>
</div>
<div class="paragraph">
<p>The <a href="nng_stat_child.3.html"><code>nng_stat_child()</code></a> and
<a href="nng_stat_next.3.html"><code>nng_stat_next()</code></a> function can be used to
iterate over the the tree.</p>
</div>
<div class="paragraph">
<p>When no longer needed, the statistics can be freed with the
<a href="nng_stats_free.3.html"><code>nng_stats_free()</code></a> function, but that
function must be called only with the root statistic that is returned
through the <em>statsp</em> pointer.</p>
</div>
<div class="admonitionblock note">
<table>
<tr>
<td class="icon">
<i class="fa icon-note" title="Note"></i>
</td>
<td class="content">
The values of individual statistics are guaranteed to be atomic,
but due the way statistics are collected there can be discrepancies between them at certain times.
For example, statistics counting bytes and messages received may not
reflect the same number of messages, depending on when the snapshot is taken.
This potential inconsistency arises as a result of optimizations to minimize
the impact of statistics on actual operations.
</td>
</tr>
</table>
</div>
<div class="admonitionblock note">
<table>
<tr>
<td class="icon">
<i class="fa icon-note" title="Note"></i>
</td>
<td class="content">
The names, values, and semantics of statistics provided may change
from release to release.
These are provided for informational and debugging use only, and applications
should not rely on the presence, names, or meanings of any individual statistics.
</td>
</tr>
</table>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_return_values">RETURN VALUES</h2>
<div class="sectionbody">
<div class="paragraph">
<p>This function returns a pointer to the allocated memory on success,
and <code>NULL</code> otherwise.</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_errors">ERRORS</h2>
<div class="sectionbody">
<div class="hdlist">
<table>
<tr>
<td class="hdlist1">
<code>NNG_ENOMEM</code>
</td>
<td class="hdlist2">
<p>Insufficient free memory to collect statistics.</p>
</td>
</tr>
<tr>
<td class="hdlist1">
<code>NNG_ENOTSUP</code>
</td>
<td class="hdlist2">
<p>Statistics are not supported (compile time option).</p>
</td>
</tr>
</table>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_see_also">SEE ALSO</h2>
<div class="sectionbody">
<div class="paragraph text-left">
<p><a href="nng_stats_free.3.html">nng_stats_free(3)</a>,
<a href="nng_stat_child.3.html">nng_stat_child(3)</a>,
<a href="nng_stat_desc.3.html">nng_stat_desc(3)</a>,
<a href="nng_stat_name.3.html">nng_stat_name(3)</a>,
<a href="nng_stat_next.3.html">nng_stat_next(3)</a>,
<a href="nng_stat_string.3.html">nng_stat_string(3)</a>,
<a href="nng_stat_type.3.html">nng_stat_type(3)</a>,
<a href="nng_stat_timestamp.3.html">nng_stat_timestamp(3)</a>,
<a href="nng_stat_unit.3.html">nng_stat_unit(3)</a>,
<a href="nng_stat_value.3.html">nng_stat_value(3)</a>,
<a href="nng_stat.5.html">nng_stat(5)</a>,
<a href="nng.7.html">nng(7)</a></p>
</div>
</div>
</div>
|
