read_next_info
magic = read_next_info(pf, 4);
uint64_t cur_ts = read_next_info(pf, 4) * NS_SCALE +
read_next_info(pf, 4) * pf->resolution;
uint32_t caplen = read_next_info(pf, 4);
uint32_t len = read_next_info(pf, 4);
cur_ts = read_next_info(pf, 4) * NS_SCALE +
read_next_info(pf, 4) * pf->resolution;
q->cur_caplen = read_next_info(pf, 4);
q->cur_len = read_next_info(pf, 4);