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man: document sd_print() and friends
2012-07-09 15:46:21 +02:00
<?xml version='1.0'?> <!--*-nxml-*-->
man: use same header for all files The "include" files had type "book" for some raeason. I don't think this is meaningful. Let's just use the same everywhere. $ perl -i -0pe 's^..DOCTYPE (book|refentry) PUBLIC "-//OASIS//DTD DocBook XML V4.[25]//EN"\s+"http^<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"\n "http^gms' man/*.xml
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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
man: use same version in public and system ident.
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"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
license: LGPL-2.1+ -> LGPL-2.1-or-later
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<!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
man: document sd_print() and friends
2012-07-09 15:46:21 +02:00
man: xinclude pkg-config note
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<refentry id="sd-journal"
Reindent man pages to 2ch
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xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>sd-journal</title>
<productname>systemd</productname>
</refentryinfo>
<refmeta>
<refentrytitle>sd-journal</refentrytitle>
<manvolnum>3</manvolnum>
</refmeta>
<refnamediv>
<refname>sd-journal</refname>
<refpurpose>APIs for submitting and querying log entries to and
from the journal</refpurpose>
</refnamediv>
<refsynopsisdiv>
<funcsynopsis>
<funcsynopsisinfo>#include &lt;systemd/sd-journal.h&gt;</funcsynopsisinfo>
</funcsynopsis>
<cmdsynopsis>
<command>pkg-config --cflags --libs libsystemd</command>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
man: add libsystemd(3) Before libsystemd-daemon, libsystemd-journal, libsystemd-id128, etc., were merged into libsystemd, it was enough to have individual man pages for them. But they have been delivered as one thing for many years, so it's better to have a landing page for libsystemd. It mostly directs to individual pages anyway.
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<para><filename>sd-journal.h</filename> is part of
<citerefentry><refentrytitle>libsystemd</refentrytitle><manvolnum>3</manvolnum></citerefentry> and
provides APIs to submit and query log entries. The APIs exposed act both as client for the
Reindent man pages to 2ch
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<citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
journal service and as parser for the journal files on disk.
</para>
<para>See
<citerefentry><refentrytitle>sd_journal_print</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_stream_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_open</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_add_match</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_seek_head</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
sd-journal: add an API to enumerate known field names of the journal This adds two new calls to get the list of all journal fields names currently in use. This is the low-level support to implement the feature requested in #2176 in a more optimized way.
2016-01-27 18:59:29 +01:00
<citerefentry><refentrytitle>sd_journal_enumerate_fields</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
Reindent man pages to 2ch
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<citerefentry><refentrytitle>sd_journal_get_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_get_cutoff_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_get_cutoff_monotonic_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_get_usage</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
sd-journal: introduce has_runtime_files and has_persistent_files Also introduce sd_journal_has_runtime_files() and sd_journal_has_persistent_files() to the public API. These functions can be used to easily find out if the open journal files are runtime and/or persistent.
2016-02-01 09:23:58 +01:00
<citerefentry><refentrytitle>sd_journal_get_catalog</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_journal_has_runtime_files</refentrytitle><manvolnum>3</manvolnum></citerefentry>
Reindent man pages to 2ch
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and
sd-journal: introduce has_runtime_files and has_persistent_files Also introduce sd_journal_has_runtime_files() and sd_journal_has_persistent_files() to the public API. These functions can be used to easily find out if the open journal files are runtime and/or persistent.
2016-02-01 09:23:58 +01:00
<citerefentry><refentrytitle>sd_journal_has_persistent_files</refentrytitle><manvolnum>3</manvolnum></citerefentry>
Reindent man pages to 2ch
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for more information about the functions implemented.</para>
<para>Command line access for submitting entries to the journal is
available with the
<citerefentry><refentrytitle>systemd-cat</refentrytitle><manvolnum>1</manvolnum></citerefentry>
tool. Command line access for querying entries from the journal is
available with the
<citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
tool.</para>
</refsect1>
man: add notes about thread safety of sd_journal_* functions Fixes #4056.
2016-10-15 15:24:55 -04:00
<refsect1>
<title>Thread safety</title>
man: fix advice regarding thread safety of libsystemd The prohibition to move libsystemd objects between threads was added in 64a7ef8bc06b5dcfcd9f99ea10a43bde75c4370f ('man: be more explicit about thread safety of sd_journal'). At the time, this was valid, because we were using the mempool for allocation and it apparently didn't handle access from different threads. Sadlly, the commit links to a bugzilla entry referenced in the commit is not publicly visible anymore, so the details are murky. But we stopped using the mempool in a5d8835c78112206bbf0812dd4cb471f803bfe88 ('mempool: only enable mempool use when linked to libsystemd-shared.so'), with subsequent followup in b01f31954f1c7c4601925173ae2638b572224e9a ('Turn mempool_enabled() into a weak symbol'). The restriction added in the man page is not necessary since then. The text in the man page was arguably incorrect in calling the code "thread-agnostic". If the code does not support being touched from threads at all and has global state to tied to the main thread, it is not "agnostic", but just doesn't support threads. (I'm looking into https://github.com/systemd/python-systemd/issues/143, and with the current scheme, the python-systemd module and all python code using libsystemd would be very hard to use. With the change to free-threaded python in python3.13, i.e. the replacement of single Global Interpreter Lock by locking on individual objects, this limitation would become even more constraining.)
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<para>Functions that operate on <structname>sd_journal</structname> objects are thread agnostic — a given
<structname>sd_journal</structname> pointer may only be used from one thread at a time, but multiple
independent threads may use multiple objects concurrently. Some functions — those that are used to send
entries to the journal, like
<citerefentry><refentrytitle>sd_journal_print</refentrytitle><manvolnum>3</manvolnum></citerefentry> and
similar, or those that are used to retrieve global information like
<citerefentry><refentrytitle>sd_journal_stream_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>
and
man: add notes about thread safety of sd_journal_* functions Fixes #4056.
2016-10-15 15:24:55 -04:00
<citerefentry><refentrytitle>sd_journal_get_catalog_for_message_id</refentrytitle><manvolnum>3</manvolnum></citerefentry>
man: be more explicit about thread safety of sd_journal Triggered by https://bugzilla.redhat.com/show_bug.cgi?id=1609349 This adds two generic paragaphs we include via xinclude. One is the "strict" version, which contains wording saying that we are thread agnostic and what that means. And the other is the "safe" version, for the cases we provide fully safety. Let's then change most man pages to use either of these generic paragraphs. With one exception: man/sd_journal_get_catalog.xml contains both kinds of function, we hence use manual wording.
2018-08-03 16:43:30 +02:00
— are fully thread-safe and may be called from multiple threads in parallel.</para>
man: add notes about thread safety of sd_journal_* functions Fixes #4056.
2016-10-15 15:24:55 -04:00
</refsect1>
man: document that using sd_journal APIs might cause dlopen to happen
2024-03-31 14:22:54 +01:00
<refsect1>
<title>Optional dependencies</title>
<para>Depending on which build-time options are enabled, functions that operate on
<structname>sd_journal</structname> objects might cause optional shared libraries to be dynamically
loaded via
man/sd-journal: correct project name for man7 Follow-up for 5aa818039230a08e0af1c6351de4794de8ebb778
2024-04-14 23:46:31 +08:00
<citerefentry project='man-pages'><refentrytitle>dlopen</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
man: document that using sd_journal APIs might cause dlopen to happen
2024-03-31 14:22:54 +01:00
such as decompression libraries (xz, lz4, zstd) or cryptographic libraries (gcrypt).
</para>
</refsect1>
Reindent man pages to 2ch
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<xi:include href="libsystemd-pkgconfig.xml" />
<refsect1>
<title>See Also</title>
man: use <simplelist> for 'See also' sections This is just a slight markup improvement; there should be no difference in rendering.
2023-12-22 19:09:32 +01:00
<para><simplelist type="inline">
<member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_print</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_stream_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_open</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_next</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_get_data</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_add_match</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_seek_head</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_enumerate_fields</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_get_cursor</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_get_cutoff_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_get_cutoff_monotonic_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_get_usage</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_query_unique</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_get_catalog</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_has_runtime_files</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd_journal_has_persistent_files</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
<member><citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
</simplelist></para>
Reindent man pages to 2ch
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</refsect1>
man: document sd_print() and friends
2012-07-09 15:46:21 +02:00
</refentry>
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