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</style><a href="index.html">Index </a>·
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<a href="../libudev/index.html">gudev </a><span style="float:right">systemd 219</span><hr><div class="refentry"><a name="sd_journal_get_cutoff_realtime_usec"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>sd_journal_get_cutoff_realtime_usec, sd_journal_get_cutoff_monotonic_usec — Read cut-off timestamps from the current journal entry</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><pre class="funcsynopsisinfo">#include &lt;systemd/sd-journal.h&gt;</pre><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_journal_get_cutoff_realtime_usec</b>(</code></td><td>sd_journal *<var class="pdparam">j</var>, </td></tr><tr><td> </td><td>uint64_t *<var class="pdparam">from</var>, </td></tr><tr><td> </td><td>uint64_t *<var class="pdparam">to</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_journal_get_cutoff_monotonic_usec</b>(</code></td><td>sd_journal *<var class="pdparam">j</var>, </td></tr><tr><td> </td><td>sd_id128_t <var class="pdparam">boot_id</var>, </td></tr><tr><td> </td><td>uint64_t *<var class="pdparam">from</var>, </td></tr><tr><td> </td><td>uint64_t *<var class="pdparam">to</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="idm139661284739216"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description"></a></h2><p><code class="function">sd_journal_get_cutoff_realtime_usec()</code>
retrieves the realtime (wallclock) timestamps of the first and
last entries accessible in the journal. It takes three arguments:
the journal context object <em class="parameter"><code>j</code></em> and two
pointers <em class="parameter"><code>from</code></em> and <em class="parameter"><code>to</code></em>
pointing at 64-bit unsigned integers to store the timestamps in.
The timestamps are in microseconds since the epoch, i.e.
<code class="constant">CLOCK_REALTIME</code>. Either one of the two
timestamp arguments may be passed as <code class="constant">NULL</code> in
case the timestamp is not needed, but not both.</p><p><code class="function">sd_journal_get_cutoff_monotonic_usec()</code>
retrieves the monotonic timestamps of the first and last entries
accessible in the journal. It takes three arguments: the journal
context object <em class="parameter"><code>j</code></em>, a 128-bit identifier for
the boot <em class="parameter"><code>boot_id</code></em>, and two pointers to
64-bit unsigned integers to store the timestamps,
<em class="parameter"><code>from</code></em> and <em class="parameter"><code>to</code></em>. The
timestamps are in microseconds since boot-up of the specific boot,
i.e. <code class="constant">CLOCK_MONOTONIC</code>. Since the monotonic
clock begins new with every reboot it only defines a well-defined
point in time when used together with an identifier identifying
the boot, see
<a href="sd_id128_get_boot.html"><span class="citerefentry"><span class="refentrytitle">sd_id128_get_boot</span>(3)</span></a>
for more information. The function will return the timestamps for
the boot identified by the passed boot ID. Either one of the two
timestamp arguments may be passed as <code class="constant">NULL</code> in
case the timestamp is not needed, but not both.</p></div><div class="refsect1"><a name="idm139661288682112"></a><h2 id="Return Value">Return Value<a class="headerlink" title="Permalink to this headline" href="#Return%20Value"></a></h2><p><code class="function">sd_journal_get_cutoff_realtime_usec()</code>
and <code class="function">sd_journal_get_cutoff_monotonic_usec()</code>
return 1 on success, 0 if not suitable entries are in the journal
or a negative errno-style error code.</p><p>Locations pointed to by parameters
<em class="parameter"><code>from</code></em> and <em class="parameter"><code>to</code></em> will be
set only if the return value is positive, and obviously, the
parameters are non-null.</p></div><div class="refsect1"><a name="idm139661288677568"></a><h2 id="Notes">Notes<a class="headerlink" title="Permalink to this headline" href="#Notes"></a></h2><p>The
<code class="function">sd_journal_get_cutoff_realtime_usec()</code> and
<code class="function">sd_journal_get_cutoff_monotonic_usec()</code>
interfaces are available as a shared library, which can be
compiled and linked to with the
<code class="constant">libsystemd</code> <a href="http://linux.die.net/man/1/pkg-config"><span class="citerefentry"><span class="refentrytitle">pkg-config</span>(1)</span></a>
file.</p></div><div class="refsect1"><a name="idm139661288673184"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also"></a></h2><p>
<a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>,
<a href="sd-journal.html"><span class="citerefentry"><span class="refentrytitle">sd-journal</span>(3)</span></a>,
<a href="sd_journal_open.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_open</span>(3)</span></a>,
<a href="sd_journal_get_realtime_usec.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_get_realtime_usec</span>(3)</span></a>,
<a href="sd_id128_get_boot.html"><span class="citerefentry"><span class="refentrytitle">sd_id128_get_boot</span>(3)</span></a>,
<a href="http://man7.org/linux/man-pages/man2/clock_gettime.2.html"><span class="citerefentry"><span class="refentrytitle">clock_gettime</span>(2)</span></a>
</p></div></div></body></html>