G'day sjwnih111,

Welcome to the monastery.

If you're just looking for a difference between that time today and the current time today, you can use the builtin module, Time::Piece, like this:

$ perl -Mstrict -Mwarnings -le '
    use Time::Piece;

    my $now = gmtime;
    my $now_Ymd_date = sprintf "%4s%02s%02s", $now->year, $now->mon, $
+now->mday;

    my $then_HMS_time = "082802";
    my $then_date_time = $now_Ymd_date . $then_HMS_time;
    my $then = Time::Piece->strptime($then_date_time, "%Y%m%d%H%M%S");

    print "Then: ", $then->strftime("%Y-%m-%d %H:%M:%S");
    print "Now:  ", $now->strftime("%Y-%m-%d %H:%M:%S");
    print "Now - Then: ", $now - $then, " seconds";
'
Then: 2013-09-11 08:28:02
Now:  2013-09-11 01:44:18
Now - Then: -24224 seconds
[download]

Note that gives a negative time difference because it's not elapsed time at all, it's ~7 hours in the future. To get an elapsed time, you'll need to provide a date and time in the past to compare with the current date and time. This is what hippo was referring to.

Of course, if you're piloting a time machine, negative elapsed times might be entirely appropriate. :-)