Know your command line switches ... and you can save a few keystrokes :) perl -ne 'my ($h, $w) = split; next unless $w; @l = split /\s+/, `ac -p $w`; printf "%20s: %5d logins %8s total time \n", $l[1], $h, $l[2];'

Update: As CheeseLord remarked, you can additionally employ the -a switch leading to: perl -ane 'next unless $F[1]; @l = split /\s+/, `ac -p $F[1]`; printf "%20s: %5d logins %8s total time \n", $l[1], $F[0], $l[2];'

Update2: Fixed an overlooked $w in my update, thanks CheeseLord for spotting that as well :)

-- Hofmator