FWIW, I used Time::Local for a one-liner: 
perl -MTime::Local=timelocal -e 'print scalar localtime timelocal qw(3
+0 40 2 15 8 2012)';

[download]
Update: to get the day, date, and time 48 days ago: 
#!/usr/bin/perl -l

use strict;
use autodie;
use warnings;
use POSIX 'strftime';
use Time::Local 'timelocal';

my $days_ago = '48';
($days_ago)  = strftime("%d", gmtime(
    time - $days_ago * 86400
));

print scalar localtime timelocal(
    30, 40, 2, $days_ago, 7, 2012,
);

[download]

In reply to Re: Use 'strftime' to calculate a date/time in the Past. by Khen1950fx
in thread Use 'strftime' to calculate a date/time in the Past. by mmartin

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