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<body class="manpage">
<div id="header">
<h1>
libtraceevent(3) Manual Page
</h1>
<h2>NAME</h2>
<div class="sectionbody">
<p>kbuffer_read_event, kbuffer_next_event, kbuffer_missed_events, kbuffer_event_size, kbuffer_curr_size, kbuffer_curr_offset, kbuffer_curr_index, kbuffer_read_buffer -
Functions to read through the kbuffer sub buffer.
</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 <kbuffer.h></strong>
void *<strong>kbuffer_read_event</strong>(struct kbuffer *<em>kbuf</em>, unsigned long long *<em>ts</em>);
void *<strong>kbuffer_next_event</strong>(struct kbuffer *<em>kbuf</em>, unsigned long long *<em>ts</em>);
void *<strong>kbuffer_read_at_offset</strong>(struct kbuffer *<em>kbuf</em>, int <em>offset</em>, unsigned long long *<em>ts</em>);
int <strong>kbuffer_missed_events</strong>(struct kbuffer *<em>kbuf</em>);
int <strong>kbuffer_event_size</strong>(struct kbuffer *<em>kbuf</em>);
int <strong>kbuffer_curr_size</strong>(struct kbuffer *<em>kbuf</em>);
int <strong>kbuffer_curr_offset</strong>(struct kbuffer *<em>kbuf</em>);
int <strong>kbuffer_curr_index</strong>(struct kbuffer *<em>kbuf</em>);
int <strong>kbuffer_read_buffer</strong>(struct kbuffer *<em>kbuf</em>, void *<em>buffer</em>, int <em>len</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 function <strong>kbuffer_read_event()</strong> reads the next event in the <em>kbuf</em> descriptor
and if <em>ts</em> is non NULL, will place its timestamp into it. This does not modify the <em>kbuf</em>
descriptor, and calling this function mulitple times will return the same result.</p></div>
<div class="paragraph"><p>The function <strong>kbuffer_next_event()</strong> will return the next event in the <em>kbuf</em> descriptor.
It will also set the <em>ts</em> to the timestamp of the returned event. NULL is returned
if there are no more events and <em>ts</em> will be undefined. Note, if this is called directly
after a <strong>kbuffer_load_subbuffer()</strong> then it will likely give an unexpected result, as it
will return the second event and not the first event. Usually this function is only used
to move to the next event and to know if there’s any more events to read, and
<strong>kbuffer_read_event()</strong> is always called first.</p></div>
<div class="paragraph"><p>The function <strong>kbuffer_read_at_offset()</strong> returns the event located at a given <em>offset</em> from
the beginning of the sub-buffer. This offset can be retrieved by <strong>kbuffer_curr_offset()</strong>.
If <em>ts</em> points to an unsigned long long, then it will be set to the event at the given
offset’s timestamp.</p></div>
<div class="paragraph"><p>If the sub-buffer had missed events before it, then <strong>kbuffer_missed_events()</strong> will return
the non zero. If it returns -1, that means there were missed events, but the exact number
of missed events is unknown. If it returns a positive number, then the number of missed events
is the return value.</p></div>
<div class="paragraph"><p>The <strong>kbuffer_event_size()</strong> function returns the size of the data portion of the current event
(the one that would be returned by <strong>kbuffer_read_event()</strong>.</p></div>
<div class="paragraph"><p>The <strong>kbuffer_curr_size()</strong> function returns the entire record size of the current event
(the one that would be returned by <strong>kbuffer_read_event()</strong>. The difference here is that the
return value includes the size of the event record meta data that is not part of what
is returned by <strong>kbuffer_read_event()</strong>.</p></div>
<div class="paragraph"><p>The <strong>kbuffer_curr_offset()</strong> function returns the offset from the beginning of the sub-buffer
of where the current event’s meta data for the record begins. The first event will
not be at offset zero. This offset can be used to retrieve the event with
<strong>kbuffer_read_at_offset()</strong>.</p></div>
<div class="paragraph"><p>The <strong>kbuffer_curr_index()</strong> function returns the index from the beginning of the data
portion of the sub-buffer where the current evnet’s meta data is located.
The first event will likely be zero, but may not be if there’s a timestamp attached to it.</p></div>
<div class="paragraph"><p>The <strong>kbuffer_read_buffer()</strong> function will fill the given <em>buffer</em> from the <em>kbuf</em> the same
way the kernel would do a read system call. That is, if the length <em>len</em> is less than the
sub buffer size, or the kbuffer current index is non-zero, it will start copying from the
<em>kbuf</em> current event and create <em>buffer</em> as a new sub buffer (with a timestamp
and commit header) with that event that was found and including all events after that can
fit within <em>len</em>. The <em>len</em> must include the size of the sub buffer header as well as the
events to include. That is, <em>len</em> is the allocate size of <em>buffer</em> that can be filled.
The return from this function is the index of the end of the last event that was added.
If there are no more events then zero is returned, and if the buffer can not
copy any events because <em>len</em> was too small, then -1 is returned.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_return_value">RETURN VALUE</h2>
<div class="sectionbody">
<div class="paragraph"><p><strong>kbuffer_read_event()</strong> returns the event that the <em>kbuf</em> descriptor is currently at,
or NULL if the last event was passed (by <strong>kbuffer_next_event()</strong>).</p></div>
<div class="paragraph"><p><strong>kbuffer_next_event()</strong> returns the next event after the current event or NULL if there
are no more events.</p></div>
<div class="paragraph"><p><strong>kbuffer_read_at_offset()</strong> returns the event at a given <em>offset</em> from the start of
the sub-buffer stored in <em>kbuf</em>, or NULL if there exists no event. Note, <em>offset</em>
only needs to be an offset that lands on the record, or is at the start of it. It does
not need to be exactly at the beginning of the record.</p></div>
<div class="paragraph"><p><strong>kbuffer_missed_events()</strong> returns 0 if there were no missed events before loaded sub-buffer.
Returns -1 if there were an unknown number of missed events, or if the number of missed events
is known, that number will be returned.</p></div>
<div class="paragraph"><p><strong>kbuffer_event_size()</strong> returns the size of the data payload of the current event of <em>kbuf</em>.</p></div>
<div class="paragraph"><p><strong>kbuffer_curr_size()</strong> returns the size of the entire record of the current event of <em>kbuf</em>.
This includes the size of the meta data for that record.</p></div>
<div class="paragraph"><p><strong>kbuf_curr_offset()</strong> returns the offset of the current record from the beginning of the <em>kbuf</em>
sub-buffer.</p></div>
<div class="paragraph"><p><strong>kbuf_curr_index()</strong> returns the index of the current record from the beginning of the <em>kbuf</em>
data section.</p></div>
<div class="paragraph"><p><strong>kbuf_read_buffer()</strong> returns the index of the end of the last event that was filled in
<em>buffer</em>. If there are no more events to copy from <em>start</em> then 0 is returned. If <em>len</em>
is not big enough to hold any events, then -1 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"><stdio.h></span>
<span style="font-weight: bold"><span style="color: #000080">#include</span></span> <span style="color: #FF0000"><stdlib.h></span>
<span style="font-weight: bold"><span style="color: #000080">#include</span></span> <span style="color: #FF0000"><fcntl.h></span>
<span style="font-weight: bold"><span style="color: #000080">#include</span></span> <span style="color: #FF0000"><unistd.h></span>
<span style="font-weight: bold"><span style="color: #000080">#include</span></span> <span style="color: #FF0000"><sys/stat.h></span>
<span style="font-weight: bold"><span style="color: #000080">#include</span></span> <span style="color: #FF0000"><kbuffer.h></span>
<span style="color: #009900">int</span> <span style="font-weight: bold"><span style="color: #000000">main</span></span> <span style="color: #990000">(</span><span style="color: #009900">int</span> argc<span style="color: #990000">,</span> <span style="color: #009900">char</span> <span style="color: #990000">**</span>argv<span style="color: #990000">)</span>
<span style="color: #FF0000">{</span>
<span style="color: #009900">unsigned</span> <span style="color: #009900">long</span> <span style="color: #009900">long</span> ts<span style="color: #990000">;</span>
<span style="font-weight: bold"><span style="color: #0000FF">struct</span></span> <span style="color: #008080">kbuffer</span> <span style="color: #990000">*</span>kbuf<span style="color: #990000">;</span>
<span style="font-weight: bold"><span style="color: #0000FF">struct</span></span> <span style="color: #008080">stat</span> st<span style="color: #990000">;</span>
<span style="color: #009900">char</span> <span style="color: #990000">*</span>buf<span style="color: #990000">;</span>
<span style="color: #009900">void</span> <span style="color: #990000">*</span>event<span style="color: #990000">;</span>
<span style="color: #009900">int</span> save_offset <span style="color: #990000">=</span> <span style="color: #990000">-</span><span style="color: #993399">1</span><span style="color: #990000">;</span>
<span style="color: #009900">int</span> record_size<span style="color: #990000">;</span>
<span style="color: #009900">int</span> offset<span style="color: #990000">;</span>
<span style="color: #009900">int</span> index<span style="color: #990000">;</span>
<span style="color: #009900">int</span> size<span style="color: #990000">;</span>
<span style="color: #009900">int</span> ret<span style="color: #990000">;</span>
<span style="color: #009900">int</span> fd<span style="color: #990000">;</span>
<span style="color: #009900">int</span> i <span style="color: #990000">=</span> <span style="color: #993399">0</span><span style="color: #990000">;</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(</span>argc <span style="color: #990000"><</span> <span style="color: #993399">2</span><span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
<span style="font-weight: bold"><span style="color: #000000">printf</span></span><span style="color: #990000">(</span><span style="color: #FF0000">"usage: %s raw-subbuffer-page</span><span style="color: #CC33CC">\n</span><span style="color: #FF0000">"</span><span style="color: #990000">,</span> argv<span style="color: #990000">[</span><span style="color: #993399">0</span><span style="color: #990000">]);</span>
<span style="font-weight: bold"><span style="color: #000000">printf</span></span><span style="color: #990000">(</span><span style="color: #FF0000">" Try: dd count=1 bs=4096 if=/sys/kernel/tracing/per_cpu/cpu0/trace_pipe_raw of=/tmp/file</span><span style="color: #CC33CC">\n</span><span style="color: #FF0000">"</span><span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #000000">exit</span></span><span style="color: #990000">(</span><span style="color: #993399">0</span><span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(</span><span style="font-weight: bold"><span style="color: #000000">stat</span></span><span style="color: #990000">(</span>argv<span style="color: #990000">[</span><span style="color: #993399">1</span><span style="color: #990000">],</span> <span style="color: #990000">&</span>st<span style="color: #990000">)</span> <span style="color: #990000"><</span> <span style="color: #993399">0</span><span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
<span style="font-weight: bold"><span style="color: #000000">perror</span></span><span style="color: #990000">(</span><span style="color: #FF0000">"stat"</span><span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #000000">exit</span></span><span style="color: #990000">(-</span><span style="color: #993399">1</span><span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
buf <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">malloc</span></span><span style="color: #990000">(</span>st<span style="color: #990000">.</span>st_size<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(!</span>buf<span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
<span style="font-weight: bold"><span style="color: #000000">perror</span></span><span style="color: #990000">(</span><span style="color: #FF0000">"Allocating buffer"</span><span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #000000">exit</span></span><span style="color: #990000">(-</span><span style="color: #993399">1</span><span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
fd <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">open</span></span><span style="color: #990000">(</span>argv<span style="color: #990000">[</span><span style="color: #993399">1</span><span style="color: #990000">],</span> O_RDONLY<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(</span>fd <span style="color: #990000"><</span> <span style="color: #993399">0</span><span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
<span style="font-weight: bold"><span style="color: #000000">perror</span></span><span style="color: #990000">(</span>argv<span style="color: #990000">[</span><span style="color: #993399">1</span><span style="color: #990000">]);</span>
<span style="font-weight: bold"><span style="color: #000000">exit</span></span><span style="color: #990000">(-</span><span style="color: #993399">1</span><span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
ret <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">read</span></span><span style="color: #990000">(</span>fd<span style="color: #990000">,</span> buf<span style="color: #990000">,</span> st<span style="color: #990000">.</span>st_size<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(</span>ret <span style="color: #990000"><</span> <span style="color: #993399">0</span><span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
<span style="font-weight: bold"><span style="color: #000000">perror</span></span><span style="color: #990000">(</span><span style="color: #FF0000">"Reading buffer"</span><span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #000000">exit</span></span><span style="color: #990000">(-</span><span style="color: #993399">1</span><span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
<span style="font-weight: bold"><span style="color: #000000">close</span></span><span style="color: #990000">(</span>fd<span style="color: #990000">);</span>
kbuf <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_alloc</span></span><span style="color: #990000">(</span>KBUFFER_ENDIAN_SAME_AS_HOST<span style="color: #990000">,</span>
KBUFFER_LSIZE_SAME_AS_HOST<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(!</span>kbuf<span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
<span style="font-weight: bold"><span style="color: #000000">perror</span></span><span style="color: #990000">(</span><span style="color: #FF0000">"Creating kbuffer"</span><span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #000000">exit</span></span><span style="color: #990000">(-</span><span style="color: #993399">1</span><span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
ret <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_load_subbuffer</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">,</span> buf<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(</span>ret <span style="color: #990000"><</span> <span style="color: #993399">0</span><span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
<span style="font-weight: bold"><span style="color: #000000">perror</span></span><span style="color: #990000">(</span><span style="color: #FF0000">"Loading sub bufer"</span><span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #000000">exit</span></span><span style="color: #990000">(-</span><span style="color: #993399">1</span><span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(</span><span style="font-weight: bold"><span style="color: #000000">kbuffer_subbuffer_size</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">)</span> <span style="color: #990000">></span> st<span style="color: #990000">.</span>st_size<span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
<span style="font-weight: bold"><span style="color: #000000">fprintf</span></span><span style="color: #990000">(</span>stderr<span style="color: #990000">,</span> <span style="color: #FF0000">"kbuffer is bigger than raw size %d > %ld</span><span style="color: #CC33CC">\n</span><span style="color: #FF0000">"</span><span style="color: #990000">,</span>
<span style="font-weight: bold"><span style="color: #000000">kbuffer_subbuffer_size</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">),</span> st<span style="color: #990000">.</span>st_size<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #000000">exit</span></span><span style="color: #990000">(-</span><span style="color: #993399">1</span><span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
ret <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_missed_events</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(</span>ret<span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(</span>ret <span style="color: #990000">></span> <span style="color: #993399">0</span><span style="color: #990000">)</span>
<span style="font-weight: bold"><span style="color: #000000">printf</span></span><span style="color: #990000">(</span><span style="color: #FF0000">"Missed %d events before this buffer</span><span style="color: #CC33CC">\n</span><span style="color: #FF0000">"</span><span style="color: #990000">,</span> ret<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">else</span></span>
<span style="font-weight: bold"><span style="color: #000000">printf</span></span><span style="color: #990000">(</span><span style="color: #FF0000">"Missed unknown number of events before this buffer</span><span style="color: #CC33CC">\n</span><span style="color: #FF0000">"</span><span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
<span style="font-weight: bold"><span style="color: #0000FF">do</span></span> <span style="color: #FF0000">{</span>
event <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_read_event</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">,</span> <span style="color: #990000">&</span>ts<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(</span>event<span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
record_size <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_curr_size</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">);</span>
offset <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_curr_offset</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">);</span>
index <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_curr_index</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">);</span>
size <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_event_size</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(</span>i <span style="color: #990000">==</span> <span style="color: #993399">20</span><span style="color: #990000">)</span>
save_offset <span style="color: #990000">=</span> offset<span style="color: #990000">;</span>
<span style="font-weight: bold"><span style="color: #000000">printf</span></span><span style="color: #990000">(</span><span style="color: #FF0000">" event %3d ts:%lld</span><span style="color: #CC33CC">\t</span><span style="color: #FF0000">record_size:%d size:%d</span><span style="color: #CC33CC">\t</span><span style="color: #FF0000">index:%d offset:%d</span><span style="color: #CC33CC">\n</span><span style="color: #FF0000">"</span><span style="color: #990000">,</span>
i<span style="color: #990000">++,</span> ts<span style="color: #990000">,</span> record_size<span style="color: #990000">,</span> size<span style="color: #990000">,</span> index<span style="color: #990000">,</span> offset<span style="color: #990000">);</span>
event <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_next_event</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">,</span> NULL<span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
<span style="color: #FF0000">}</span> <span style="font-weight: bold"><span style="color: #0000FF">while</span></span> <span style="color: #990000">(</span>event<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(!</span>event<span style="color: #990000">)</span>
<span style="font-weight: bold"><span style="color: #000000">printf</span></span><span style="color: #990000">(</span><span style="color: #FF0000">"Finished sub buffer</span><span style="color: #CC33CC">\n</span><span style="color: #FF0000">"</span><span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(</span>save_offset <span style="color: #990000">></span> <span style="color: #993399">0</span><span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
event <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_read_at_offset</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">,</span> save_offset<span style="color: #990000">,</span> <span style="color: #990000">&</span>ts<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">if</span></span> <span style="color: #990000">(!</span>event<span style="color: #990000">)</span> <span style="color: #FF0000">{</span>
<span style="font-weight: bold"><span style="color: #000000">fprintf</span></span><span style="color: #990000">(</span>stderr<span style="color: #990000">,</span> <span style="color: #FF0000">"Funny, can't find event 20 at offset %d</span><span style="color: #CC33CC">\n</span><span style="color: #FF0000">"</span><span style="color: #990000">,</span> save_offset<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #000000">exit</span></span><span style="color: #990000">(-</span><span style="color: #993399">1</span><span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
record_size <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_curr_size</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">);</span>
offset <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_curr_offset</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">);</span>
index <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_curr_index</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">);</span>
size <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">kbuffer_event_size</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #000000">printf</span></span><span style="color: #990000">(</span><span style="color: #FF0000">"</span><span style="color: #CC33CC">\n</span><span style="color: #FF0000"> saved event 20 ts:%lld</span><span style="color: #CC33CC">\t</span><span style="color: #FF0000">record_size:%d size:%d</span><span style="color: #CC33CC">\t</span><span style="color: #FF0000">index:%d offset:%d</span><span style="color: #CC33CC">\n\n</span><span style="color: #FF0000">"</span><span style="color: #990000">,</span>
ts<span style="color: #990000">,</span> record_size<span style="color: #990000">,</span> size<span style="color: #990000">,</span> index<span style="color: #990000">,</span> offset<span style="color: #990000">);</span>
<span style="color: #FF0000">}</span>
<span style="font-weight: bold"><span style="color: #000000">kbuffer_free</span></span><span style="color: #990000">(</span>kbuf<span style="color: #990000">);</span>
<span style="font-weight: bold"><span style="color: #0000FF">return</span></span> <span style="color: #993399">0</span><span style="color: #990000">;</span>
<span style="color: #FF0000">}</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>.</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>
<div class="sectionbody">
<div class="paragraph"><p>libtraceevent is Free Software licensed under the GNU LGPL 2.1</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_resources">RESOURCES</h2>
<div class="sectionbody">
<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>
</div>
</div>
</div>
<div id="footnotes"><hr /></div>
<div id="footer">
<div id="footer-text">
Last updated
2024-10-11 21:26:45 UTC
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