systemd Developer Lennart Poettering lennart@poettering.net sd_journal_seek_head 3 sd_journal_seek_head sd_journal_seek_tail sd_journal_seek_monotonic_usec sd_journal_seek_realtime_usec sd_journal_seek_cursor Seek to a position in the journal #include <systemd/sd-journal.h> int sd_journal_seek_head sd_journal* j int sd_journal_seek_tail sd_journal* j int sd_journal_seek_monotonic_usec sd_journal* j sd_id128_t boot_id uint64_t usec int sd_journal_seek_realtime_usec sd_journal* j uint64_t usec int sd_journal_seek_cursor sd_journal* j const char * cursor sd_journal_seek_head() seeks to the beginning of the journal, i.e. the oldest avilable entry. Similar, sd_journal_seek_tail() may be used to seek to the end of the journal, i.e. the most recent available entry. sd_journal_seek_monotonic_usec() seeks to the entry with the specified monotonic timestamp, i.e. CLOCK_MONOOTONIC. Since monotonic time restarts on every reboot a boot ID needs to be specified as well. sd_journal_seek_realtime_usec() seeks to the entry with the specified realtime (wallclock) timestamp, i.e. CLOCK_REALTIME. Note that the realtime clock is not necessary monotonic. If a realtime timestamp is ambiguous it is not defined which position is seeked to. sd_journal_seek_cursor() seeks to the entry located at the specified cursor string. For details on cursors see sd_journal_get_cursor3. Note that these calls do not actually make any entry the new current entry, this needs to be done in a separate step with a subsequent sd_journal_next3 invocation (or a similar call). Only then entry data may be retrieved via sd_journal_get_data3. If no entry exists that matches exactly the specified seek address the next closest is seeked to. If sd_journal_next3 is used the closest following entry will be seeked to, if sd_journal_previous3 is used the closest preceeding entry is seeked to. The functions return 0 on success or a negative errno-style error code. The sd_journal_seek_head(), sd_journal_seek_tail(), sd_journal_seek_monotonic_usec(), sd_journal_seek_realtime_usec(), and sd_journal_seek_cursor() interfaces are available as shared library, which can be compiled and linked to with the libsystemd-journal pkg-config1 file. systemd1, sd-journal3, sd_journal_open3, sd_journal_next3, sd_journal_get_data3, sd_journal_get_cursor3, sd_journal_get_realtime_usec3