NAME

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

SYNOPSIS

       #include <systemd/sd-journal.h>

       pkg-config --cflags --libs libsystemd

DESCRIPTION

       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

       Functions that operate on the sd_journal object are thread agnostic — given sd_journal pointer may only
       be used from one thread at a time, but multiple threads may use multiple such 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 thread-safe and may be called from multiple threads in
       parallel.

NOTES

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

SEE ALSO

       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)