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
+ 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:
- <literal>SD_JOURNAL_LOCAL_ONLY</literal> makes sure
+ <constant>SD_JOURNAL_LOCAL_ONLY</constant> makes sure
only journal files generated on the local machine will
- be opened. <literal>SD_JOURNAL_RUNTIME_ONLY</literal>
+ 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. <literal>SD_JOURNAL_SYSTEM</literal>
+ 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. <literal>SD_JOURNAL_CURRENT_USER</literal>
+ be opened. <constant>SD_JOURNAL_CURRENT_USER</constant>
will cause journal files of the current user to be
- opened. If neither <literal>SD_JOURNAL_SYSTEM</literal>
- nor <literal>SD_JOURNAL_CURRENT_USER</literal> are
+ 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>
<para><function>sd_journal_open_files()</function>
is similar to <function>sd_journal_open()</function>
- but takes a <literal>NULL</literal>-terminated list
+ 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.</para>
+ 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_close()</function> will
close the journal context allocated with
<para>See
<citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- for an example how to iterate through the journal
+ for an example of how to iterate through the journal
after opening it with
<function>sd_journal_open()</function>.</para>
<refsect1>
<title>Return Value</title>
- <para>The <function>sd_journal_open()</function> and
- <function>sd_journal_open_directory()</function> calls
+ <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>
<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
+ available as a shared library, which can be compiled and
linked to with the
- <literal>libsystemd-journal</literal>
- <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ <constant>libsystemd-journal</constant> <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
file.</para>
</refsect1>
<para><function>sd_journal_open()</function>,
<function>sd_journal_close()</function>,
- <literal>SD_JOURNAL_LOCAL_ONLY</literal>,
- <literal>SD_JOURNAL_RUNTIME_ONLY</literal>,
- <literal>SD_JOURNAL_SYSTEM_ONLY</literal> were added
+ <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><literal>SD_JOURNAL_SYSTEM</literal>,
- <literal>SD_JOURNAL_CURRENT_USER</literal>,
+ <para><constant>SD_JOURNAL_SYSTEM</constant>,
+ <constant>SD_JOURNAL_CURRENT_USER</constant>,
and <function>sd_journal_open_files()</function>
were added in systemd-205.
- <literal>SD_JOURNAL_SYSTEM_ONLY</literal>
+ <constant>SD_JOURNAL_SYSTEM_ONLY</constant>
was deprecated.</para>
</refsect1>