s/[\n\r]+$// for (@ip);

##</code><code>##

my @ip;
{  
  local $/ = "\n";
  open my $dat, "<:raw", $in_file or die "Can't open file $in_file: $!";
  @ip = <$dat>;
  s/[\n\r]+$// for (@ip);
  close $dat;
}