# untested
while (<>)
{
   my ($mon, $day, $time, $rtr, $seqno, $rmon, $rday, $rtime, $rtz, $code, $msg) = split(' ', $_, 11);
   next unless $code =~ m!\%SEC-6-IPACCESSLOGP:|\%SEC-6-IPACCESSLOGDP:!:
   # process stuff here, ala:
   my (undef, $listno, $act, $proto, $src, undef, $trget, $other, $cnt, ) = split(' ', $msg);
}