Simple perl, designed to extract from wtmp, users who haven't login in over 365 days, it is the template that causing the headache 
#!/usr/local/bin/perl

print $template = "A8 A4 A12 l s s s s l a16 l";
$recordsize = length(pack($template,( )));

open(WTMP,"/var/adm/wtmp") or die "Unable to open wtmp:$!\n";
while (read(WTMP,$record,$recordsize)) {
        ($user,$ttyid,$tty,$pid,$type,$term,$exit,$host,$time,$hostip)
+=unpack
($template,$record);
        next unless $type == 7;
        next unless $ttyid;
        next if $ttyid eq "ftp";
        next if $ttyid=~/\d+:\d+/;

        $user=~y/\000//d; $ttyid=~y/\000//d; $tty=~y/\000//d; $host=~y
+/\000//d;
        $hold{$user}=$time if $time >$hold{$user};
}

$over365=time()-365*24*60*60;
foreach $user (keys %hold) {
        if ($hold{$user} < $over365) { printf( "%12s %d\n", $user, $ho
+ld{$user}
); }
};

[download]
_________________________________________ OUTPUT LOOKS LIKE THIS: 
A8 A4 A12 l s s s s l a16 l     kileykl 1043180949
     romanst 1042640335
    hallchar 1033636020
      orsjrg 1035913589
    dindiala 1035210784
    smithpau 1045754579
      orsbll 1042571980
      orsmjr 1043676426
      orsawb 1036078160

[download]

In reply to Issues with wtmp by lost_in_space

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