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diff --git a/man/sd_journal_next.xml b/man/sd_journal_next.xml deleted file mode 100644 index 7c385de260..0000000000 --- a/man/sd_journal_next.xml +++ /dev/null @@ -1,210 +0,0 @@ -<?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_next"> - - <refentryinfo> - <title>sd_journal_next</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_next</refentrytitle> - <manvolnum>3</manvolnum> - </refmeta> - - <refnamediv> - <refname>sd_journal_next</refname> - <refname>sd_journal_previous</refname> - <refname>sd_journal_next_skip</refname> - <refname>sd_journal_previous_skip</refname> - <refname>SD_JOURNAL_FOREACH</refname> - <refname>SD_JOURNAL_FOREACH_BACKWARDS</refname> - <refpurpose>Advance or set back the read pointer in the journal</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcsynopsisinfo>#include <systemd/sd-journal.h></funcsynopsisinfo> - - <funcprototype> - <funcdef>int <function>sd_journal_next</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_journal_previous</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_journal_next_skip</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - <paramdef>uint64_t <parameter>skip</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_journal_previous_skip</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - <paramdef>uint64_t <parameter>skip</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef><function>SD_JOURNAL_FOREACH</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef><function>SD_JOURNAL_FOREACH_BACKWARDS</function></funcdef> - <paramdef>sd_journal *<parameter>j</parameter></paramdef> - </funcprototype> - </funcsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - - <para><function>sd_journal_next()</function> advances the read - pointer into the journal by one entry. The only argument taken is - a journal context object as allocated via - <citerefentry><refentrytitle>sd_journal_open</refentrytitle><manvolnum>3</manvolnum></citerefentry>. - After successful invocation the entry may be read with functions - such as - <citerefentry><refentrytitle>sd_journal_get_data</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para> - - <para>Similarly, <function>sd_journal_previous()</function> sets - the read pointer back one entry.</para> - - <para><function>sd_journal_next_skip()</function> and - <function>sd_journal_previous_skip()</function> advance/set back - the read pointer by multiple entries at once, as specified in the - <varname>skip</varname> parameter.</para> - - <para>The journal is strictly ordered by reception time, and hence - advancing to the next entry guarantees that the entry then - pointing to is later in time than then previous one, or has the - same timestamp.</para> - - <para>Note that - <citerefentry><refentrytitle>sd_journal_get_data</refentrytitle><manvolnum>3</manvolnum></citerefentry> - and related calls will fail unless - <function>sd_journal_next()</function> has been invoked at least - once in order to position the read pointer on a journal - entry.</para> - - <para>Note that the <function>SD_JOURNAL_FOREACH()</function> - macro may be used as a wrapper around - <citerefentry><refentrytitle>sd_journal_seek_head</refentrytitle><manvolnum>3</manvolnum></citerefentry> - and <function>sd_journal_next()</function> in order to make - iterating through the journal easier. See below for an example. - Similarly, <function>SD_JOURNAL_FOREACH_BACKWARDS()</function> may - be used for iterating the journal in reverse order.</para> - </refsect1> - - <refsect1> - <title>Return Value</title> - - <para>The four calls return the number of entries advanced/set - back on success or a negative errno-style error code. When the end - or beginning of the journal is reached, a number smaller than - requested is returned. More specifically, if - <function>sd_journal_next()</function> or - <function>sd_journal_previous()</function> reach the end/beginning - of the journal they will return 0, instead of 1 when they are - successful. This should be considered an EOF marker.</para> - </refsect1> - - <refsect1> - <title>Notes</title> - - <para>All functions listed here are thread-agnostic and only a single thread may operate - on a given <structname>sd_journal</structname> object.</para> - - <para>The <function>sd_journal_next()</function>, - <function>sd_journal_previous()</function>, - <function>sd_journal_next_skip()</function> and - <function>sd_journal_previous_skip()</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>Examples</title> - - <para>Iterating through the journal:</para> - - <programlisting>#include <stdio.h> -#include <string.h> -#include <systemd/sd-journal.h> - -int main(int argc, char *argv[]) { - int r; - sd_journal *j; - r = sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY); - if (r < 0) { - fprintf(stderr, "Failed to open journal: %s\n", strerror(-r)); - return 1; - } - SD_JOURNAL_FOREACH(j) { - const char *d; - size_t l; - - r = sd_journal_get_data(j, "MESSAGE", (const void **)&d, &l); - if (r < 0) { - fprintf(stderr, "Failed to read message field: %s\n", strerror(-r)); - continue; - } - - printf("%.*s\n", (int) l, d); - } - sd_journal_close(j); - return 0; -}</programlisting> - - </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_data</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_journal_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd_journal_get_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry> - </para> - </refsect1> - -</refentry> |