int sd_journal_seek_head(sd_journal *j);
int sd_journal_seek_tail(sd_journal *j);
-int sd_journal_seek_seqnum(sd_journal *j, uint64_t seqnum);
int sd_journal_seek_monotonic_usec(sd_journal *j, uint64_t usec);
int sd_journal_seek_realtime_usec(sd_journal *j, uint64_t usec);