#!/usr/local/bin/perl 

use strict;
use warnings;

my $now = time();
my $before = $now - 3 * 24 * 3600; # drei Tage

# ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) 
my @loc = localtime($before);

my $datebeforestring = sprintf( "%04d-%02d-%02d", $loc[5]+1900, $loc[4], $loc[3] );  

print $datebeforestring;

1;