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sd_journal_get_realtime_usec(3) [centos man page]

SD_JOURNAL_GET_REALTIME_USEC(3) 			   sd_journal_get_realtime_usec 			   SD_JOURNAL_GET_REALTIME_USEC(3)

NAME
sd_journal_get_realtime_usec, sd_journal_get_monotonic_usec - Read timestamps from the current journal entry SYNOPSIS
#include <systemd/sd-journal.h> int sd_journal_get_realtime_usec(sd_journal* j, uint64_t* usec); int sd_journal_get_monotonic_usec(sd_journal* j, uint64_t* usec, sd_id128_t* boot_id); DESCRIPTION
sd_journal_get_realtime_usec() gets the realtime (wallclock) timestamp of the current journal entry. It takes two arguments: the journal context object and a pointer to a 64-bit unsigned integer to store the timestamp in. The timestamp is in microseconds since the epoch, i.e. CLOCK_REALTIME. sd_journal_get_monotonic_usec() gets the monotonic timestamp of the current journal entry. It takes three arguments: the journal context object, a pointer to a 64-bit unsigned integer to store the timestamp in, as well as a 128-bit ID buffer to store the boot ID of the monotonic timestamp. The timestamp is 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. If the boot ID parameter is passed NULL, the function will fail if the monotonic timestamp of the current entry is not of the current system boot. Note that these functions will not work before sd_journal_next(3) (or related call) has been called at least once, in order to position the read pointer at a valid entry. RETURN VALUE
sd_journal_get_realtime_usec() and sd_journal_get_monotonic_usec() returns 0 on success or a negative errno-style error code. If the boot ID parameter was passed NULL and the monotonic timestamp of the current journal entry is not of the current system boot, -ESTALE is returned by sd_journal_get_monotonic_usec(). NOTES
The sd_journal_get_realtime_usec() and sd_journal_get_monotonic_usec() interfaces are available as a shared library, which can be compiled and linked to with the libsystemd-journal pkg-config(1) file. SEE ALSO
systemd(1), sd-journal(3), sd_journal_open(3), sd_journal_next(3), sd_journal_get_data(3), sd_id128_get_boot(3), clock_gettime(2), sd_journal_get_cutoff_realtime_usec(3) systemd 208 SD_JOURNAL_GET_REALTIME_USEC(3)

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SD_JOURNAL_GET_CUTOFF_REALTIME_USEC(3)			sd_journal_get_cutoff_realtime_usec		    SD_JOURNAL_GET_CUTOFF_REALTIME_USEC(3)

NAME
sd_journal_get_cutoff_realtime_usec, sd_journal_get_cutoff_monotonic_usec - Read cut-off timestamps from the current journal entry SYNOPSIS
#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); DESCRIPTION
sd_journal_get_cutoff_realtime_usec() gets the realtime (wallclock) timestamps of the first and last entries accessible in the journal. It takes three arguments: the journal context object and two pointers to 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() gets the monotonic timestamps of the first and last entries accessible in the journal. It takes three arguments: the journal context object, a 128-bit identifier for the boot, and two pointers to 64-bit unsigned integers to store the timestamps. 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. RETURN VALUE
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. NOTES
The sd_journal_get_cutoff_realtime_usec() and sd_journal_get_cutoff_monotonic_usec() interfaces are available as a shared library, which can be compiled and linked to with the libsystemd-journal pkg-config(1) file. SEE ALSO
systemd(1), sd-journal(3), sd_journal_open(3), sd_journal_get_realtime_usec(3), sd_id128_get_boot(3), clock_gettime(2) systemd 208 SD_JOURNAL_GET_CUTOFF_REALTIME_USEC(3)

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