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<body class="manpage">
<div id="header">
<h1>
libtraceevent(3) Manual Page
</h1>
<h2>NAME</h2>
<div class="sectionbody">
<p>tep_read_number -
   Reads a number from raw data.
</p>
</div>
</div>
<div id="content">
<div class="sect1">
<h2 id="_synopsis">SYNOPSIS</h2>
<div class="sectionbody">
<div class="verseblock">
<pre class="content"><strong>#include <event-parse.h></strong>

unsigned long long <strong>tep_read_number</strong>(struct tep_handle *<em>tep</em>, const void *<em>ptr</em>, int <em>size</em>);</pre>
<div class="attribution">
</div></div>
</div>
</div>
<div class="sect1">
<h2 id="_description">DESCRIPTION</h2>
<div class="sectionbody">
<div class="paragraph"><p>The <strong>tep_read_number()</strong> function reads an integer from raw data, taking into
account the endianness of the raw data and the current host. The <em>tep</em> argument
is the trace event parser context. The <em>ptr</em> is a pointer to the raw data, where
the integer is, and the <em>size</em> is the size of the integer.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_return_value">RETURN VALUE</h2>
<div class="sectionbody">
<div class="paragraph"><p>The <strong>tep_read_number()</strong> function returns the integer in the byte order of
the current host. In case of an error, 0 is returned.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_example">EXAMPLE</h2>
<div class="sectionbody">
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #000080">#include</span></span> <span style="color: #FF0000"><event-parse.h></span>
<span style="color: #990000">...</span>
<span style="font-weight: bold"><span style="color: #0000FF">struct</span></span> <span style="color: #008080">tep_handle</span> <span style="color: #990000">*</span>tep <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">tep_alloc</span></span><span style="color: #990000">();</span>
<span style="color: #990000">...</span>
<span style="color: #009900">void</span> <span style="font-weight: bold"><span style="color: #000000">process_record</span></span><span style="color: #990000">(</span><span style="font-weight: bold"><span style="color: #0000FF">struct</span></span> <span style="color: #008080">tep_record</span> <span style="color: #990000">*</span>record<span style="color: #990000">)</span>
<span style="color: #FF0000">{</span>
        <span style="color: #009900">int</span> offset <span style="color: #990000">=</span> <span style="color: #993399">24</span><span style="color: #990000">;</span>
        <span style="color: #009900">int</span> data <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">tep_read_number</span></span><span style="color: #990000">(</span>tep<span style="color: #990000">,</span> record<span style="color: #990000">-></span>data <span style="color: #990000">+</span> offset<span style="color: #990000">,</span> <span style="color: #993399">4</span><span style="color: #990000">);</span>

        <span style="font-style: italic"><span style="color: #9A1900">/* Read the 4 bytes at the offset 24 of data as an integer */</span></span>
<span style="color: #FF0000">}</span>
<span style="color: #990000">...</span></tt></pre></div></div>
</div>
</div>
<div class="sect1">
<h2 id="_files">FILES</h2>
<div class="sectionbody">
<div class="verseblock">
<pre class="content"><strong>event-parse.h</strong>
        Header file to include in order to have access to the library APIs.
<strong>-ltraceevent</strong>
        Linker switch to add when building a program that uses the library.</pre>
<div class="attribution">
</div></div>
</div>
</div>
<div class="sect1">
<h2 id="_see_also">SEE ALSO</h2>
<div class="sectionbody">
<div class="paragraph"><p><strong>libtraceevent</strong>(3), <strong>trace-cmd</strong>(1)</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_author">AUTHOR</h2>
<div class="sectionbody">
<div class="verseblock">
<pre class="content"><strong>Steven Rostedt</strong> <<a href="mailto:rostedt@goodmis.org">rostedt@goodmis.org</a>>, author of <strong>libtraceevent</strong>.
<strong>Tzvetomir Stoyanov</strong> <<a href="mailto:tz.stoyanov@gmail.com">tz.stoyanov@gmail.com</a>>, author of this man page.</pre>
<div class="attribution">
</div></div>
</div>
</div>
<div class="sect1">
<h2 id="_reporting_bugs">REPORTING BUGS</h2>
<div class="sectionbody">
<div class="paragraph"><p>Report bugs to  <<a href="mailto:linux-trace-devel@vger.kernel.org">linux-trace-devel@vger.kernel.org</a>></p></div>
</div>
</div>
<div class="sect1">
<h2 id="_license">LICENSE</h2>
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<div class="paragraph"><p>libtraceevent is Free Software licensed under the GNU LGPL 2.1</p></div>
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<h2 id="_resources">RESOURCES</h2>
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<div class="paragraph"><p><a href="https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/">https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/</a></p></div>
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Last updated
 2022-03-24 23:40:51 UTC
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