Time::Seconds and Time::Piece are core modules, they do not need to be installed, and Date::Calc, already mentioned in this thread, is used to calculate the arbitrary date. But sure, how about this, then?

Update: changed hour to noon, instead of midnight, thanks daylight saving time (now works for the week of March 14 2010, thanks ikegami) 
use strict;
use warnings;

sub get_bofw {
        my $time = shift;
        my @t    = localtime($time);
        my $bow  = $time - ($t[6] * 86400);
        localtime($bow);
}

# Tue Mar 16 2010 12pm
my $bofw = get_bofw(1268766000);

print "$bofw\n";

[download]

Update: Adding Time::Local, to make the call a little more clear: 
use strict;
use warnings;

sub get_bofw {
        my $time = shift;
        my @t    = localtime($time);
        my $bow  = $time - ($t[6] * 86400);
        localtime($bow);
}

# Tue Mar 16 2010 12pm
my $time = timelocal(0,0,12,21,4,74);
my $bofw = get_bofw($time);

print "$bofw\n";

[download]

In reply to Re^5: Is there an easy way to get the start date of the current week? by james2vegas
in thread Is there an easy way to get the start date of the current week? by ramjamman

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