use strict;
use File::Copy;
use POSIX;

my @files = ('system.csv', 'sales.csv'); 
my $home = 'c:/EOD/20 January 2002/';    
my $archive = 'y:/New EOD/';             

my $yesterday = strftime("%d%m%y", localtime(time - 24*60*60));

for (@files){
  copy $home.$_, "$archive${yesterday}_$_"
    or print "ERROR: Can't copy $_ : $!\n";
}