1SD-JOURNAL(3)                     sd-journal                     SD-JOURNAL(3)
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NAME

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

10       #include <systemd/sd-journal.h>
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12       pkg-config --cflags --libs libsystemd
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DESCRIPTION

15       sd-journal.h provides APIs to submit and query log entries. The APIs
16       exposed act both as client for the systemd-journald.service(8) journal
17       service and as parser for the journal files on disk.
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19       See sd_journal_print(3), sd_journal_stream_fd(3), sd_journal_open(3),
20       sd_journal_next(3), sd_journal_get_realtime_usec(3),
21       sd_journal_add_match(3), sd_journal_seek_head(3),
22       sd_journal_enumerate_fields(3), sd_journal_get_cursor(3),
23       sd_journal_get_cutoff_realtime_usec(3),
24       sd_journal_get_cutoff_monotonic_usec(3), sd_journal_get_usage(3),
25       sd_journal_get_catalog(3), sd_journal_get_fd(3),
26       sd_journal_has_runtime_files(3) and sd_journal_has_persistent_files(3)
27       for more information about the functions implemented.
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29       Command line access for submitting entries to the journal is available
30       with the systemd-cat(1) tool. Command line access for querying entries
31       from the journal is available with the journalctl(1) tool.
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THREAD SAFETY

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

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

50       systemd(1), sd_journal_print(3), sd_journal_stream_fd(3),
51       sd_journal_open(3), sd_journal_next(3), sd_journal_get_data(3),
52       sd_journal_get_realtime_usec(3), sd_journal_add_match(3),
53       sd_journal_seek_head(3), sd_journal_enumerate_fields(3),
54       sd_journal_get_cursor(3), sd_journal_get_cutoff_realtime_usec(3),
55       sd_journal_get_cutoff_monotonic_usec(3), sd_journal_get_usage(3),
56       sd_journal_get_fd(3), sd_journal_query_unique(3),
57       sd_journal_get_catalog(3), sd_journal_has_runtime_files(3),
58       sd_journal_has_persistent_files(3), journalctl(1), sd-id128(3), pkg-
59       config(1)
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63systemd 249                                                      SD-JOURNAL(3)