$ date; gzip -dc message*.gz | sed -n 's/^.*\(@@.......\).*$/\1/p' | sort | uniq -c; date;
Wed Mar 26 16:34:41 HKT 2014
1 @@URS0016
3 @@URS0072
7 @@URS0273
7 @@URS0347
5 @@URS0399
Wed Mar 26 16:35:00 HKT 2014
19s
$ date; gzip -dc message*.gz | grep @@ | sed -n 's/^.*\(@@.......\).*$/\1/p' | sort | uniq -c; date;
Wed Mar 26 16:35:04 HKT 2014
1 @@URS0016
3 @@URS0072
7 @@URS0273
7 @@URS0347
5 @@URS0399
Wed Mar 26 16:35:10 HKT 2014
6s