mirror of
https://github.com/systemd/systemd.git
synced 2024-11-01 17:51:22 +03:00
bb31a4ac19
https://bugs.freedesktop.org/show_bug.cgi?id=55890
Fixed typos, serial comma, and removed "either" as there were more
than two options. Also did an extra rename of "system-shutdown"
to "systemd-shutdown" that was forgotten in commit
8bd3b8620c
185 lines
8.8 KiB
XML
185 lines
8.8 KiB
XML
<?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_open">
|
|
|
|
<refentryinfo>
|
|
<title>sd_journal_open</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_open</refentrytitle>
|
|
<manvolnum>3</manvolnum>
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname>sd_journal_open</refname>
|
|
<refname>sd_journal_open_directory</refname>
|
|
<refname>sd_journal_close</refname>
|
|
<refname>sd_journal</refname>
|
|
<refname>SD_JOURNAL_LOCAL_ONLY</refname>
|
|
<refname>SD_JOURNAL_RUNTIME_ONLY</refname>
|
|
<refname>SD_JOURNAL_SYSTEM_ONLY</refname>
|
|
<refpurpose>Open the system journal for reading</refpurpose>
|
|
</refnamediv>
|
|
|
|
<refsynopsisdiv>
|
|
<funcsynopsis>
|
|
<funcsynopsisinfo>#include <systemd/sd-journal.h></funcsynopsisinfo>
|
|
|
|
<funcprototype>
|
|
<funcdef>int <function>sd_journal_open</function></funcdef>
|
|
<paramdef>sd_journal** <parameter>ret</parameter></paramdef>
|
|
<paramdef>int <parameter>flags</parameter></paramdef>
|
|
</funcprototype>
|
|
|
|
<funcprototype>
|
|
<funcdef>int <function>sd_journal_open_directory</function></funcdef>
|
|
<paramdef>sd_journal** <parameter>ret</parameter></paramdef>
|
|
<paramdef>const char* <parameter>path</parameter></paramdef>
|
|
<paramdef>int <parameter>flags</parameter></paramdef>
|
|
</funcprototype>
|
|
|
|
<funcprototype>
|
|
<funcdef>int <function>sd_journal_close</function></funcdef>
|
|
<paramdef>sd_journal* <parameter>j</parameter></paramdef>
|
|
</funcprototype>
|
|
</funcsynopsis>
|
|
</refsynopsisdiv>
|
|
|
|
<refsect1>
|
|
<title>Description</title>
|
|
|
|
<para><function>sd_journal_open()</function> opens
|
|
the log journal for reading. It will find all journal
|
|
files automatically and interleave them automatically
|
|
when reading. As first argument it takes a pointer to
|
|
a <literal>sd_journal</literal> pointer, which on
|
|
success will contain journal context object afterwards. The
|
|
second argument is a flags field, which may consist of
|
|
the following flags ORed together:
|
|
<literal>SD_JOURNAL_LOCAL_ONLY</literal> makes sure
|
|
only journal files generated on the local machine will
|
|
be opened. <literal>SD_JOURNAL_RUNTIME_ONLY</literal>
|
|
makes sure only volatile journal files will be opened,
|
|
excluding those which are stored on persistent
|
|
storage. <literal>SD_JOURNAL_SYSTEM_ONLY</literal>
|
|
will ensure that only journal files of system services
|
|
and the kernel (in opposition to user session processes) will
|
|
be opened.</para>
|
|
|
|
<para><function>sd_journal_open_directory()</function>
|
|
is similar to <function>sd_journal_open()</function>
|
|
but takes an absolute directory path as argument. All
|
|
journal files in this directory will be opened and
|
|
interleaved automatically. This call also takes a
|
|
flags argument, but it must be passed as 0 as no flags
|
|
are currently understood for this call.</para>
|
|
|
|
<para><function>sd_journal_close()</function> will
|
|
close the journal context allocated with
|
|
<function>sd_journal_open()</function> or
|
|
<function>sd_journal_open_directory()</function> and
|
|
free its resources.</para>
|
|
|
|
<para>When opening the journal only journal files
|
|
accessible to the calling user will be opened. If
|
|
journal files are not accessible to the caller this
|
|
will be silently ignored.</para>
|
|
|
|
<para>See
|
|
<citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
|
for an example how to iterate through the journal
|
|
after opening it with
|
|
<function>sd_journal_open()</function>.</para>
|
|
|
|
<para>A journal context object returned by
|
|
<function>sd_journal_open()</function> references a
|
|
specific journal entry as <emphasis>current</emphasis> entry,
|
|
similar to a file seek index in a classic file system
|
|
file, but without absolute positions. It may be
|
|
altered with
|
|
<citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
|
and
|
|
<citerefentry><refentrytitle>sd_journal_seek_head</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
|
and related calls. The current entry position may be
|
|
exported in <emphasis>cursor</emphasis> strings, as accessible
|
|
via
|
|
<citerefentry><refentrytitle>sd_journal_get_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>. Cursor
|
|
strings may be used to globally identify a specific
|
|
journal entry in a stable way and then later to seek
|
|
to it (or if the specific entry is not available
|
|
locally, to its closest entry in time)
|
|
<citerefentry><refentrytitle>sd_journal_seek_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
|
|
|
|
<para>Notification of journal changes is available via
|
|
<function>sd_journal_get_fd()</function> and related
|
|
calls.</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Return Value</title>
|
|
|
|
<para>The <function>sd_journal_open()</function> and
|
|
<function>sd_journal_open_directory()</function> calls
|
|
return 0 on success or a negative errno-style error
|
|
code. <function>sd_journal_close()</function> returns
|
|
nothing.</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Notes</title>
|
|
|
|
<para>The <function>sd_journal_open()</function>,
|
|
<function>sd_journal_open_directory()</function> and
|
|
<function>sd_journal_close()</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_next</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>sd_journal_get_data</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
|
</para>
|
|
</refsect1>
|
|
|
|
</refentry>
|