Date/time manipulations--formatting, calculating deltas etc--is one case where I would definitely advocate not rolling your own. I mostly use Date::Manip (although it is, in the authors words, probably the slowest of the Date/Time modules) and despite the fact that the pod itself needs pod. I beleive Date::Calc is nearly as flexible and a lot faster.

An example of using Date:Manip might help you decide. The following shows the script itself and using it to get the delta between two dates in seconds, minutes, hours, days and weeks.

C:\test>type datemanip.pl
#! perl -slw
use strict;
use Date::Manip;

print Delta_Format( 
    DateCalc( 
        ParseDate($ARGV[0]),
        ParseDate($ARGV[1]) 
    )
    , 0, $ARGV[2]||'%dh'
);


C:\test>datemanip " 2/28/2000 11:57:29 PM" " 3/1/2000 1:40:03 pm" %st
135754.000000

C:\test>datemanip " 2/28/2000 11:57:29 PM" " 3/1/2000 1:40:03 pm" %mt
2262.566667

C:\test>datemanip " 2/28/2000 11:57:29 PM" " 3/1/2000 1:40:03 pm" %ht
37.709444

C:\test>datemanip " 2/28/2000 11:57:29 PM" " 3/1/2000 1:40:03 pm" %dt
1.571227

C:\test>datemanip " 2/28/2000 11:57:29 PM" " 3/1/2000 1:40:03 pm" %wt
0.224461
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