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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">
+
+<!--
+ SPDX-License-Identifier: LGPL-2.1+
+-->
+
+<refentry id="sd_journal_get_cursor" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_journal_get_cursor</title>
+ <productname>systemd</productname>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_journal_get_cursor</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_journal_get_cursor</refname>
+ <refname>sd_journal_test_cursor</refname>
+ <refpurpose>Get cursor string for or test cursor string against the current journal entry</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include &lt;systemd/sd-journal.h&gt;</funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_journal_get_cursor</function></funcdef>
+ <paramdef>sd_journal *<parameter>j</parameter></paramdef>
+ <paramdef>char **<parameter>cursor</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_journal_test_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_get_cursor()</function> returns a
+ cursor string for the current journal entry. A cursor is a
+ serialization of the current journal position formatted as text.
+ The string only contains printable characters and can be passed
+ around in text form. The cursor identifies a journal entry
+ globally and in a stable way and may be used to later seek to it
+ via
+ <citerefentry><refentrytitle>sd_journal_seek_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
+ The cursor string should be considered opaque and not be parsed by
+ clients. Seeking to a cursor position without the specific entry
+ being available locally will seek to the next closest (in terms of
+ time) available entry. The call takes two arguments: a journal
+ context object and a pointer to a string pointer where the cursor
+ string will be placed. The string is allocated via libc
+ <citerefentry project='man-pages'><refentrytitle>malloc</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ and should be freed after use with
+ <citerefentry project='man-pages'><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
+
+ <para>Note that <function>sd_journal_get_cursor()</function> 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>
+
+ <para><function>sd_journal_test_cursor()</function>
+ may be used to check whether the current position in
+ the journal matches the specified cursor. This is
+ useful since cursor strings do not uniquely identify
+ an entry: the same entry might be referred to by
+ multiple different cursor strings, and hence string
+ comparing cursors is not possible. Use this call to
+ verify after an invocation of
+ <citerefentry><refentrytitle>sd_journal_seek_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ whether the entry being sought to was actually found
+ in the journal or the next closest entry was used
+ instead.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para><function>sd_journal_get_cursor()</function> returns 0 on
+ success or a negative errno-style error code.
+ <function>sd_journal_test_cursor()</function> returns positive if
+ the current entry matches the specified cursor, 0 if it does not
+ match the specified cursor or a negative errno-style error code on
+ failure.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Notes</title>
+
+ <xi:include href="threads-aware.xml" xpointer="strict" />
+
+ <xi:include href="libsystemd-pkgconfig.xml" xpointer="pkgconfig-text"/>
+ </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_seek_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>