--- /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_seek_head">
+
+ <refentryinfo>
+ <title>sd_journal_seek_head</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_seek_head</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_journal_seek_head</refname>
+ <refname>sd_journal_seek_tail</refname>
+ <refname>sd_journal_seek_monotonic_usec</refname>
+ <refname>sd_journal_seek_realtime_usec</refname>
+ <refname>sd_journal_seek_cursor</refname>
+ <refpurpose>Seek to a position in the
+ journal</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <systemd/sd-journal.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_journal_seek_head</function></funcdef>
+ <paramdef>sd_journal* <parameter>j</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_journal_seek_tail</function></funcdef>
+ <paramdef>sd_journal* <parameter>j</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_journal_seek_monotonic_usec</function></funcdef>
+ <paramdef>sd_journal* <parameter>j</parameter></paramdef>
+ <paramdef>sd_id128_t <parameter>boot_id</parameter></paramdef>
+ <paramdef>uint64_t <parameter>usec</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_journal_seek_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_seek_cursor</function></funcdef>
+ <paramdef>sd_journal* <parameter>j</parameter></paramdef>
+ <paramdef>const char * <parameter>cursor</parameter></paramdef>
+ </funcprototype>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_journal_seek_head()</function>
+ seeks to the beginning of the journal, i.e. the oldest
+ avilable entry.</para>
+
+ <para>Similar,
+ <function>sd_journal_seek_tail()</function> may be
+ used to seek to the end of the journal, i.e. the most
+ recent available entry.</para>
+
+ <para><function>sd_journal_seek_monotonic_usec()</function>
+ seeks to the entry with the specified monotonic
+ timestamp, i.e. CLOCK_MONOOTONIC. Since monotonic time
+ restarts on every reboot a boot ID needs to be
+ specified as well.</para>
+
+ <para><function>sd_journal_seek_realtime_usec()</function>
+ seeks to the entry with the specified realtime
+ (wallclock) timestamp, i.e. CLOCK_REALTIME. Note that
+ the realtime clock is not necessary monotonic. If a
+ realtime timestamp is ambiguous it is not defined
+ which position is seeked to.</para>
+
+ <para><function>sd_journal_seek_cursor()</function>
+ seeks to the entry located at the specified cursor
+ string. For details on cursors see
+ <citerefentry><refentrytitle>sd_journal_get_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
+
+ <para>Note that these calls do not actually make any
+ entry the new current entry, this needs to be done in
+ a separate step with a subsequent
+ <citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ invocation (or a similar call). Only then entry data
+ may be retrieved via
+ <citerefentry><refentrytitle>sd_journal_get_data</refentrytitle><manvolnum>3</manvolnum></citerefentry>. If
+ no entry exists that matches exactly the specified
+ seek address the next closest is seeked to. If
+ <citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ is used the closest following entry will be seeked to,
+ if
+ <citerefentry><refentrytitle>sd_journal_previous</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ is used the closest preceeding entry is seeked
+ to.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>The functions return 0 on success or a negative
+ errno-style error code.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Notes</title>
+
+ <para>The <function>sd_journal_seek_head()</function>,
+ <function>sd_journal_seek_tail()</function>,
+ <function>sd_journal_seek_monotonic_usec()</function>,
+ <function>sd_journal_seek_realtime_usec()</function>,
+ and <function>sd_journal_seek_cursor()</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_next</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_journal_get_data</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_journal_get_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_journal_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
~ianmdlvl / elogind.git / blobdiff