This snippet uses a combination of Unix commands and a perl one-liner to format a report about what users have logged onto a server, how many times, and for how long total. I've added it to my crontab on one of my web servers, thinking that the information may come in handy someday.

Output looks like this: 

wtmp begins Wed Aug 29 13:06 2001
...
                 rob:     4 logins    26.13 total time 

#!/usr/local/bin/bash
last | tail -1; last | awk '{print $1}' | grep -v wtmp | sort | uniq -
+c | perl -e 'while (<>) {my ($h, $w) = split; next unless $w; @l = sp
+lit /\s+/, `ac -p $w`; printf "%20s: %5d logins %8s total time \n", $
+l[1], $h, $l[2]; }'

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In reply to Learning about users by ginseng

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