sd-journal(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | THREAD SAFETY | NOTES | SEE ALSO | COLOPHON

SD-JOURNAL(3)                  sd-journal                  SD-JOURNAL(3)

NAME         top

       sd-journal - APIs for submitting and querying log entries to and
       from the journal

SYNOPSIS         top

       #include <systemd/sd-journal.h>

       pkg-config --cflags --libs libsystemd

DESCRIPTION         top

       sd-journal.h provides APIs to submit and query log entries. The
       APIs exposed act both as client for the
       systemd-journald.service(8) journal service and as parser for the
       journal files on disk.

       See sd_journal_print(3), sd_journal_stream_fd(3),
       sd_journal_open(3), sd_journal_next(3),
       sd_journal_get_realtime_usec(3), sd_journal_add_match(3),
       sd_journal_seek_head(3), sd_journal_enumerate_fields(3),
       sd_journal_get_cursor(3), sd_journal_get_cutoff_realtime_usec(3),
       sd_journal_get_cutoff_monotonic_usec(3), sd_journal_get_usage(3),
       sd_journal_get_catalog(3), sd_journal_get_fd(3),
       sd_journal_has_runtime_files(3) and
       sd_journal_has_persistent_files(3) for more information about the
       functions implemented.

       Command line access for submitting entries to the journal is
       available with the systemd-cat(1) tool. Command line access for
       querying entries from the journal is available with the
       journalctl(1) tool.

THREAD SAFETY         top

       Functions that operate on sd_journal objects are thread agnostic
       — given sd_journal pointer may only be used from one specific
       thread at all times (and it has to be the very same one during
       the entire lifetime of the object), but multiple, independent
       threads may use multiple, independent objects safely. Other
       functions — those that are used to send entries to the journal,
       like sd_journal_print(3) and similar, or those that are used to
       retrieve global information like sd_journal_stream_fd(3) and
       sd_journal_get_catalog_for_message_id(3) — are fully thread-safe
       and may be called from multiple threads in parallel.

NOTES         top

       These APIs are implemented as a shared library, which can be
       compiled and linked to with the libsystemd pkg-config(1) file.

SEE ALSO         top

       systemd(1), sd_journal_print(3), sd_journal_stream_fd(3),
       sd_journal_open(3), sd_journal_next(3), sd_journal_get_data(3),
       sd_journal_get_realtime_usec(3), sd_journal_add_match(3),
       sd_journal_seek_head(3), sd_journal_enumerate_fields(3),
       sd_journal_get_cursor(3), sd_journal_get_cutoff_realtime_usec(3),
       sd_journal_get_cutoff_monotonic_usec(3), sd_journal_get_usage(3),
       sd_journal_get_fd(3), sd_journal_query_unique(3),
       sd_journal_get_catalog(3), sd_journal_has_runtime_files(3),
       sd_journal_has_persistent_files(3), journalctl(1), sd-id128(3),
       pkg-config(1)

COLOPHON         top

       This page is part of the systemd (systemd system and service
       manager) project.  Information about the project can be found at
       ⟨http://www.freedesktop.org/wiki/Software/systemd⟩.  If you have
       a bug report for this manual page, see
       ⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
       This page was obtained from the project's upstream Git repository
       ⟨https://github.com/systemd/systemd.git⟩ on 2021-04-01.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2021-04-01.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

systemd 248                                                SD-JOURNAL(3)

Pages that refer to this page: sd_journal_add_match(3)sd_journal_enumerate_fields(3)sd_journal_get_catalog(3)sd_journal_get_cursor(3)sd_journal_get_cutoff_realtime_usec(3)sd_journal_get_data(3)sd_journal_get_fd(3)sd_journal_get_realtime_usec(3)sd_journal_get_usage(3)sd_journal_has_runtime_files(3)sd_journal_next(3)sd_journal_open(3)sd_journal_print(3)sd_journal_query_unique(3)sd_journal_seek_head(3)sd_journal_stream_fd(3)systemd.directives(7)systemd.index(7)systemd.journal-fields(7)systemd-coredump(8)systemd-journald.service(8)