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systemd/man/sd_journal_get_cutoff_realtime_usec.xml

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<?xml version='1.0'?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!--
This file is part of systemd.
Copyright 2012 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
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<refentry id="sd_journal_get_cutoff_realtime_usec">
<refentryinfo>
<title>sd_journal_get_cutoff_realtime_usec</title>
<productname>systemd</productname>
<authorgroup>
<author>
<contrib>Developer</contrib>
<firstname>Lennart</firstname>
<surname>Poettering</surname>
<email>lennart@poettering.net</email>
</author>
</authorgroup>
</refentryinfo>
<refmeta>
<refentrytitle>sd_journal_get_cutoff_realtime_usec</refentrytitle>
<manvolnum>3</manvolnum>
</refmeta>
<refnamediv>
<refname>sd_journal_get_cutoff_realtime_usec</refname>
<refname>sd_journal_get_cutoff_monotonic_usec</refname>
<refpurpose>Read cut-off timestamps from the current journal entry</refpurpose>
</refnamediv>
<refsynopsisdiv>
<funcsynopsis>
<funcsynopsisinfo>#include &lt;systemd/sd-journal.h&gt;</funcsynopsisinfo>
<funcprototype>
<funcdef>int <function>sd_journal_get_cutoff_realtime_usec</function></funcdef>
<paramdef>sd_journal* <parameter>j</parameter></paramdef>
<paramdef>uint64_t* <parameter>from</parameter></paramdef>
<paramdef>uint64_t* <parameter>to</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>int <function>sd_journal_get_cutoff_monotonic_usec</function></funcdef>
<paramdef>sd_journal* <parameter>j</parameter></paramdef>
<paramdef>sd_id128_t <parameter>boot_id</parameter></paramdef>
<paramdef>uint64_t* <parameter>from</parameter></paramdef>
<paramdef>uint64_t* <parameter>to</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><function>sd_journal_get_cutoff_realtime_usec()</function>
gets the realtime (wallclock) timestamps of the first
and last entries accessible in the journal. It takes
three arguments: the journal context object and two
pointers to 64-bit unsigned integers to store the
timestamps in. The timestamps are in microseconds
since the epoch,
i.e. <constant>CLOCK_REALTIME</constant>. Either one
of the two timestamp arguments may be passed as
<constant>NULL</constant> in case the timestamp is not
needed, but not both.</para>
<para><function>sd_journal_get_cutoff_monotonic_usec()</function>
gets the monotonic timestamps of the first and last
entries accessible in the journal. It takes three
arguments: the journal context object, a 128-bit
identifier for the boot, and two pointers to 64-bit
unsigned integers to store the timestamps. The
timestamps are in microseconds since boot-up of the
specific boot,
i.e. <constant>CLOCK_MONOTONIC</constant>. 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
<citerefentry><refentrytitle>sd_id128_get_boot</refentrytitle><manvolnum>3</manvolnum></citerefentry>
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 <constant>NULL</constant> in case the
timestamp is not needed, but not both.</para>
</refsect1>
<refsect1>
<title>Return Value</title>
<para><function>sd_journal_get_cutoff_realtime_usec()</function>
and
<function>sd_journal_get_cutoff_monotonic_usec()</function>
return 1 on success, 0 if not suitable entries are in
the journal or a negative errno-style error code.</para>
</refsect1>
<refsect1>
<title>Notes</title>
<para>The
<function>sd_journal_get_cutoff_realtime_usec()</function>
and
<function>sd_journal_get_cutoff_monotonic_usec()</function>
interfaces are available as a shared library, which can
be compiled and linked to with the
<constant>libsystemd</constant> <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
file.</para>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd-journal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_open</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_id128_get_boot</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>clock_gettime</refentrytitle><manvolnum>2</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>