well this is untested code, but maybe something like this: 
compare_sites("newsite1.txt", "newsite2.txt")
  if day eq "monday..." # psuedo code

compare_sites("newsite2.txt", "newsite1.txt")
  if day eq "tuesday..." # psuedo code

sub compare_sites {
  my $file1 = shift;
  my $file2 = shift;

  open IN1, $file1;

  while(<IN1>) {
    chomp;
    $newsite1{$_}++;
  } # while

  close IN1;

  open IN2, $file2;

  while(<IN2>) {
    chomp;
    print "$_ is a new site\n" 
      if not defined($newsite1{$_});
  } # while

  close IN2;
} # compare_sites

[download]
Hopefully memory isn't a problem... but otherwise this shouldn't be too bad a solutions

UPDATE:

changed the code to a function as per tye's suggestion (and so he doesn't think I'm trying to make him look like an idiot I added this comment)... and added psuedo code for calling the function based on dates... :P

UPDATE:

changed the does not exist line to print the site name and not a number... plus it identifies that it is a new site...

In reply to Re: Comparison Of Files by gaspodethewonderdog
in thread Comparison Of Files by ImpalaSS

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