+++ /dev/null
-<?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
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
--->
-
-<refentry id="sd_journal_get_realtime_usec">
-
- <refentryinfo>
- <title>sd_journal_get_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_realtime_usec</refentrytitle>
- <manvolnum>3</manvolnum>
- </refmeta>
-
- <refnamediv>
- <refname>sd_journal_get_realtime_usec</refname>
- <refname>sd_journal_get_monotonic_usec</refname>
- <refpurpose>Read timestamps from the current journal entry</refpurpose>
- </refnamediv>
-
- <refsynopsisdiv>
- <funcsynopsis>
- <funcsynopsisinfo>#include <systemd/sd-journal.h></funcsynopsisinfo>
-
- <funcprototype>
- <funcdef>int <function>sd_journal_get_realtime_usec</function></funcdef>
- <paramdef>sd_journal *<parameter>j</parameter></paramdef>
- <paramdef>uint64_t *<parameter>usec</parameter></paramdef>
- </funcprototype>
-
- <funcprototype>
- <funcdef>int <function>sd_journal_get_monotonic_usec</function></funcdef>
- <paramdef>sd_journal *<parameter>j</parameter></paramdef>
- <paramdef>uint64_t *<parameter>usec</parameter></paramdef>
- <paramdef>sd_id128_t *<parameter>boot_id</parameter></paramdef>
- </funcprototype>
-
- </funcsynopsis>
- </refsynopsisdiv>
-
- <refsect1>
- <title>Description</title>
-
- <para><function>sd_journal_get_realtime_usec()</function> gets the
- realtime (wallclock) timestamp of the current journal entry. It
- takes two arguments: the journal context object and a pointer to a
- 64-bit unsigned integer to store the timestamp in. The timestamp
- is in microseconds since the epoch, i.e.
- <constant>CLOCK_REALTIME</constant>.</para>
-
- <para><function>sd_journal_get_monotonic_usec()</function> gets
- the monotonic timestamp of the current journal entry. It takes
- three arguments: the journal context object, a pointer to a 64-bit
- unsigned integer to store the timestamp in, as well as a 128-bit
- ID buffer to store the boot ID of the monotonic timestamp. The
- timestamp is 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. If the boot ID parameter is passed
- <constant>NULL</constant>, the function will fail if the monotonic
- timestamp of the current entry is not of the current system
- boot.</para>
-
- <para>Note that these functions will not work before
- <citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- (or related call) has been called at least
- once, in order to position the read pointer at a valid entry.</para>
- </refsect1>
-
- <refsect1>
- <title>Return Value</title>
-
- <para><function>sd_journal_get_realtime_usec()</function> and
- <function>sd_journal_get_monotonic_usec()</function> returns 0 on
- success or a negative errno-style error code. If the boot ID
- parameter was passed <constant>NULL</constant> and the monotonic
- timestamp of the current journal entry is not of the current
- system boot, <constant>-ESTALE</constant> is returned by
- <function>sd_journal_get_monotonic_usec()</function>.</para>
- </refsect1>
-
- <refsect1>
- <title>Notes</title>
-
- <para>The <function>sd_journal_get_realtime_usec()</function> and
- <function>sd_journal_get_monotonic_usec()</function> interfaces
- are available as a shared library, which can be compiled and
- linked to with the
- <constant>libsystemd</constant> <citerefentry project='die-net'><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_next</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>sd_journal_get_data</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>,
- <citerefentry><refentrytitle>sd_journal_get_cutoff_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- </para>
- </refsect1>
-
-</refentry>
~ianmdlvl / elogind.git / blobdiff