X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=man%2Fsd_journal_open.xml;h=fb572802a301c9d4275d9fe82dbf74ab39121da0;hb=5c3072eab6d2e11d89452987b017541d4654ac05;hp=eb0b8c515ec8b8aa8946f642b02590eda3428e8f;hpb=3bb55eee6aecdab6bfdbb670299fa59801145cb6;p=elogind.git

diff --git a/man/sd_journal_open.xml b/man/sd_journal_open.xml
index eb0b8c515..fb572802a 100644
--- a/man/sd_journal_open.xml
+++ b/man/sd_journal_open.xml
@@ -1,6 +1,6 @@
 <?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">
+  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
 
 <!--
   This file is part of systemd.
@@ -23,129 +23,217 @@
 
 <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>
-                <refpurpose>Open the system journal for reading</refpurpose>
-        </refnamediv>
-
-        <refsynopsisdiv>
-                <funcsynopsis>
-                        <funcsynopsisinfo>#include &lt;systemd/sd-journal.h&gt;</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
-                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 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 persistant
-                storage. <literal>SD_JOURNAL_RUNTIME_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>
-        </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>
+  <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_open_files</refname>
+    <refname>sd_journal_open_container</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</refname>
+    <refname>SD_JOURNAL_CURRENT_USER</refname>
+    <refpurpose>Open the system journal for reading</refpurpose>
+  </refnamediv>
+
+  <refsynopsisdiv>
+    <funcsynopsis>
+      <funcsynopsisinfo>#include &lt;systemd/sd-journal.h&gt;</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_open_files</function></funcdef>
+        <paramdef>sd_journal **<parameter>ret</parameter></paramdef>
+        <paramdef>const char **<parameter>paths</parameter></paramdef>
+        <paramdef>int <parameter>flags</parameter></paramdef>
+      </funcprototype>
+
+      <funcprototype>
+        <funcdef>int <function>sd_journal_open_container</function></funcdef>
+        <paramdef>sd_journal **<parameter>ret</parameter></paramdef>
+        <paramdef>const char *<parameter>machine</parameter></paramdef>
+        <paramdef>int <parameter>flags</parameter></paramdef>
+      </funcprototype>
+
+      <funcprototype>
+        <funcdef>void <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 <varname>sd_journal</varname> pointer, which
+    on success will contain a journal context object. The second
+    argument is a flags field, which may consist of the following
+    flags ORed together: <constant>SD_JOURNAL_LOCAL_ONLY</constant>
+    makes sure only journal files generated on the local machine will
+    be opened. <constant>SD_JOURNAL_RUNTIME_ONLY</constant> makes sure
+    only volatile journal files will be opened, excluding those which
+    are stored on persistent storage.
+    <constant>SD_JOURNAL_SYSTEM</constant> will cause journal files of
+    system services and the kernel (in opposition to user session
+    processes) to be opened.
+    <constant>SD_JOURNAL_CURRENT_USER</constant> will cause journal
+    files of the current user to be opened. If neither
+    <constant>SD_JOURNAL_SYSTEM</constant> nor
+    <constant>SD_JOURNAL_CURRENT_USER</constant> are specified, all
+    journal file types 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_open_files()</function> is similar to
+    <function>sd_journal_open()</function> but takes a
+    <constant>NULL</constant>-terminated list of file paths to open.
+    All files 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. Please note that in
+    the case of a live journal, this function is only useful for
+    debugging, because individual journal files can be rotated at any
+    moment, and the opening of specific files is inherently
+    racy.</para>
+
+    <para><function>sd_journal_open_container()</function> is similar
+    to <function>sd_journal_open()</function> but opens the journal
+    files of a running OS container. The specified machine name refers
+    to a container that is registered with
+    <citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+
+    <para><varname>sd_journal</varname> objects cannot be used in the
+    child after a fork. Functions which take a journal object as an
+    argument (<function>sd_journal_next()</function> and others) will
+    return <constant>-ECHILD</constant> after a fork.
+    </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 of 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>,
+    <function>sd_journal_open_directory()</function>, and
+    <function>sd_journal_open_files()</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 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>History</title>
+
+    <para><function>sd_journal_open()</function>,
+    <function>sd_journal_close()</function>,
+    <constant>SD_JOURNAL_LOCAL_ONLY</constant>,
+    <constant>SD_JOURNAL_RUNTIME_ONLY</constant>,
+    <constant>SD_JOURNAL_SYSTEM_ONLY</constant> were added in
+    systemd-38.</para>
+
+    <para><function>sd_journal_open_directory()</function> was added
+    in systemd-187.</para>
+
+    <para><constant>SD_JOURNAL_SYSTEM</constant>,
+    <constant>SD_JOURNAL_CURRENT_USER</constant>, and
+    <function>sd_journal_open_files()</function> were added in
+    systemd-205. <constant>SD_JOURNAL_SYSTEM_ONLY</constant> was
+    deprecated.</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>,
+      <citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+    </para>
+  </refsect1>
 
 </refentry>