#!/usr/bin/perl



use Time::Local;

        $x = &getTime;
    sub getTime {
($sec,$min,$hour,$mday,$month,$year,$wday, $yday,$isdst)=localtime(time);
$epoch = timelocal($sec, $min, $hour, $mday, $month, $year);
return $epoch;
            }

@fileTotal = `ls /var/log/syslog*`; 
#foreach loop opens each log file
foreach $file (@fileTotal) {
chomp($file);
open(FILEREAD, "< $file");
while ($linebuf = <FILEREAD>) {
chomp($linebuf);          # remove <CR> at the end
        @data = split(/[ ]+/, $linebuf); 
                 if( $data[6] eq "session" && $data[7] eq "opened") {
                $d1 = index($linebuf, "[", 0);
                $d2 = index($linebuf, "]", ($d1+1));
                $ID = substr($linebuf, ($d1+1), ($d2-$d1-1));
                $openTime{$ID} = $epoch;
                $account{$ID} = $data[10];
                } elsif( $data[6] eq "session" && $data[7] eq "closed") {
                # user SSH logoff session
                $d1 = index($linebuf, "[", 0);
                $d2 = index($linebuf, "]", ($d1+1));
                $ID = substr($linebuf, ($d1+1), ($d2-$d1-1));
                $closeTime = $epoch; 
                if( defined $account{$ID})  {
                $userAccount = $account{$ID};
                $duration = $closeTime - $openTime{$ID}; #interval
                $totalSession{$userAccount}++;
                $dSession{$userAccount} += $duration;
                }
        }

}
close FILEREAD;

                                                                            
}
foreach $x (sort(keys %totalSession)) {
        $averageSession = $dSession{$x}/$totalSession{$x};
        printf "%-10s %10s %10s \t %.2f\n", $x,  $totalSession{$x},  $dSession{$x},  $averageSession;
}