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,
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,