eudev/man/sd_journal_get_cutoff_realtime_usec.xml
2012-07-13 20:39:05 +02:00

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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">
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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. CLOCK_REALTIME. Either one of
the two timestamp arguments may be passed as NULL 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. CLOCK_MONOTONIC. 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 NULL 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 shared library, which can
be compiled and linked to with the
<literal>libsystemd-journal</literal>
<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>