<?xml version='1.0'?> <!--*-nxml-*-->
-<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+<!-- SPDX-License-Identifier: LGPL-2.1+ -->
-<!--
- 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">
+<refentry id="sd_journal_seek_head" xmlns:xi="http://www.w3.org/2001/XInclude">
<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>
<refsect1>
<title>Description</title>
- <para><function>sd_journal_seek_head()</function> seeks to the
- beginning of the journal, i.e. the oldest available entry.</para>
+ <para><function>sd_journal_seek_head()</function> seeks to the beginning of the journal, i.e. to the
+ position before the oldest available entry.</para>
- <para>Similarly, <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>Similarly, <function>sd_journal_seek_tail()</function> may be used to seek to the end of the
+ journal, i.e. the position after 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.
- <constant>CLOCK_MONOTONIC</constant>. Since monotonic time
- restarts on every reboot a boot ID needs to be specified as
- well.</para>
+ <para><function>sd_journal_seek_monotonic_usec()</function> seeks to a position with the specified
+ monotonic timestamp, i.e. <constant>CLOCK_MONOTONIC</constant>. 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. <constant>CLOCK_REALTIME</constant>. Note that the realtime
- clock is not necessarily monotonic. If a realtime timestamp is
- ambiguous, it is not defined which position is sought to.</para>
+ <para><function>sd_journal_seek_realtime_usec()</function> seeks to a position with the specified
+ realtime (wallclock) timestamp, i.e. <constant>CLOCK_REALTIME</constant>. Note that the realtime clock is
+ not necessarily monotonic. If a realtime timestamp is ambiguous, it is not defined which position is
+ sought to.</para>
- <para><function>sd_journal_seek_cursor()</function> seeks to the
- entry located at the specified cursor string. For details on
- cursors, see
+ <para><function>sd_journal_seek_cursor()</function> seeks to the position at the specified cursor
+ string. For details on cursors, see
<citerefentry><refentrytitle>sd_journal_get_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
- If no entry matching the specified cursor is found the call will
- seek to the next closest entry (in terms of time) instead. To
- verify whether the newly selected entry actually matches the
- cursor, use
+ If no entry matching the specified cursor is found the call will seek to the next closest entry (in terms
+ of time) instead. To verify whether the newly selected entry actually matches the cursor, use
<citerefentry><refentrytitle>sd_journal_test_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 sought to. If
+ <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>
- is used, the closest following entry will be sought to, if
+ invocation (or a similar call). Only then, entry data may be retrieved via
+ <citerefentry><refentrytitle>sd_journal_get_data</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ or an entry cursor be retrieved via
+ <citerefentry><refentrytitle>sd_journal_get_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
+ If no entry exists that matches exactly the specified seek address, the next closest is sought to. If
+ <citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry> is
+ used, the closest following entry will be sought to, if
<citerefentry><refentrytitle>sd_journal_previous</refentrytitle><manvolnum>3</manvolnum></citerefentry>
is used the closest preceding entry is sought to.</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 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>
+ <xi:include href="threads-aware.xml" xpointer="strict"/>
+
+ <xi:include href="libsystemd-pkgconfig.xml" xpointer="pkgconfig-text"/>
</refsect1>
<refsect1>
projects / thirdparty / systemd.git / blobdiff