foreach my $file ("$LOGDIR\\sec-ghost01-12-09-2004-21-43.csv",
                  "$LOGDIR\\sec-ghost01-12-10-2004-21-43.csv",
                  "$LOGDIR\\sec-ghost01-12-11-2004-21-43.csv")
{
  open(INPUT,"< $file")
    or die "Can't open '$file': $!\n";
  while (my $line = <INPUT>)
  {
    chomp($line);
    # process
  }
}