1SD_JOURNAL_GET_REALTIME_USsEdC_(j3o)urnal_get_realtimeS_Du_sJeOcURNAL_GET_REALTIME_USEC(3)
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NAME

6       sd_journal_get_realtime_usec, sd_journal_get_monotonic_usec - Read
7       timestamps from the current journal entry
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SYNOPSIS

10       #include <systemd/sd-journal.h>
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12       int sd_journal_get_realtime_usec(sd_journal *j, uint64_t *usec);
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14       int sd_journal_get_monotonic_usec(sd_journal *j, uint64_t *usec,
15                                         sd_id128_t *boot_id);
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DESCRIPTION

18       sd_journal_get_realtime_usec() gets the realtime (wallclock) timestamp
19       of the current journal entry. It takes two arguments: the journal
20       context object and a pointer to a 64-bit unsigned integer to store the
21       timestamp in. The timestamp is in microseconds since the epoch, i.e.
22       CLOCK_REALTIME.
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24       sd_journal_get_monotonic_usec() gets the monotonic timestamp of the
25       current journal entry. It takes three arguments: the journal context
26       object, a pointer to a 64-bit unsigned integer to store the timestamp
27       in, as well as a 128-bit ID buffer to store the boot ID of the
28       monotonic timestamp. The timestamp is in microseconds since boot-up of
29       the specific boot, i.e.  CLOCK_MONOTONIC. Since the monotonic clock
30       begins new with every reboot, it only defines a well-defined point in
31       time when used together with an identifier identifying the boot. See
32       sd_id128_get_boot(3) for more information. If the boot ID parameter is
33       passed NULL, the function will fail if the monotonic timestamp of the
34       current entry is not of the current system boot.
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36       Note that these functions will not work before sd_journal_next(3) (or
37       related call) has been called at least once, in order to position the
38       read pointer at a valid entry.
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RETURN VALUE

41       sd_journal_get_realtime_usec() and sd_journal_get_monotonic_usec()
42       returns 0 on success or a negative errno-style error code. If the boot
43       ID parameter was passed NULL and the monotonic timestamp of the current
44       journal entry is not of the current system boot, -ESTALE is returned by
45       sd_journal_get_monotonic_usec().
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NOTES

48       All functions listed here are thread-agnostic and only a single
49       specific thread may operate on a given object during its entire
50       lifetime. It's safe to allocate multiple independent objects and use
51       each from a specific thread in parallel. However, it's not safe to
52       allocate such an object in one thread, and operate or free it from any
53       other, even if locking is used to ensure these threads don't operate on
54       it at the very same time.
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56       These APIs are implemented as a shared library, which can be compiled
57       and linked to with the libsystemd pkg-config(1) file.
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SEE ALSO

60       systemd(1), sd-journal(3), sd_journal_open(3), sd_journal_next(3),
61       sd_journal_get_data(3), sd_id128_get_boot(3), clock_gettime(2),
62       sd_journal_get_cutoff_realtime_usec(3)
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66systemd 253                                    SD_JOURNAL_GET_REALTIME_USEC(3)
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