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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | NOTES | HISTORY | SEE ALSO | COLOPHON |
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SD_JO...E_USEC(3) sd_journal_get_cutoff_realtime_usec SD_JO...E_USEC(3)
sd_journal_get_cutoff_realtime_usec,
sd_journal_get_cutoff_monotonic_usec - Read cut-off timestamps
from the current journal entry
#include <systemd/sd-journal.h>
int sd_journal_get_cutoff_realtime_usec(sd_journal *j,
uint64_t *from,
uint64_t *to);
int sd_journal_get_cutoff_monotonic_usec(sd_journal *j,
sd_id128_t boot_id,
uint64_t *from,
uint64_t *to);
sd_journal_get_cutoff_realtime_usec() retrieves the realtime
(wallclock) timestamps of the first and last entries accessible
in the journal. It takes three arguments: the journal context
object j and two pointers from and to pointing at 64-bit unsigned
integers to store the timestamps in. The timestamps are in
microseconds since the epoch, i.e. CLOCK_REALTIME. Either one of
the two timestamp arguments may be passed as NULL in case the
timestamp is not needed, but not both.
sd_journal_get_cutoff_monotonic_usec() retrieves the monotonic
timestamps of the first and last entries accessible in the
journal. It takes three arguments: the journal context object j,
a 128-bit identifier for the boot boot_id, and two pointers to
64-bit unsigned integers to store the timestamps, from and to.
The timestamps are in microseconds since boot-up of the specific
boot, i.e. CLOCK_MONOTONIC. Since the monotonic clock begins new
with every reboot it only defines a well-defined point in time
when used together with an identifier identifying the boot, see
sd_id128_get_boot(3) for more information. The function will
return the timestamps for the boot identified by the passed boot
ID. Either one of the two timestamp arguments may be passed as
NULL in case the timestamp is not needed, but not both.
sd_journal_get_cutoff_realtime_usec() and
sd_journal_get_cutoff_monotonic_usec() return 1 on success, 0 if
not suitable entries are in the journal or a negative errno-style
error code.
Locations pointed to by parameters from and to will be set only
if the return value is positive, and obviously, the parameters
are non-null.
All functions listed here are thread-agnostic and only a single
specific thread may operate on a given object during its entire
lifetime. It's safe to allocate multiple independent objects and
use each from a specific thread in parallel. However, it's not
safe to allocate such an object in one thread, and operate or
free it from any other, even if locking is used to ensure these
threads don't operate on it at the very same time.
Functions described here are available as a shared library, which
can be compiled against and linked to with the
libsystemd pkg-config(1) file.
sd_journal_get_cutoff_realtime_usec() and
sd_journal_get_cutoff_monotonic_usec() were added in version 187.
systemd(1), sd-journal(3), sd_journal_open(3),
sd_journal_get_realtime_usec(3), sd_id128_get_boot(3),
clock_gettime(2)
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 2024-06-14. (At that
time, the date of the most recent commit that was found in the
repository was 2024-06-13.) 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 257~devel SD_JO...E_USEC(3)
Pages that refer to this page: sd-journal(3), sd_journal_get_realtime_usec(3), systemd.directives(7), systemd.index(7)
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HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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