Hello, I'm attempting to parse this monster of a hosts file that is a most un-formatted file with ip4 and ip6 address with comments scattered everywhere. sometimes there are two columns separated by space, sometimes 3 columns, sometimes 4.

127.0.0.1 c2.gostats.com #SpySweeper.Spy.Cookie

127.0.0.1 ads.goyk.com

# 1-800-hostingAS3321069.41.160.0 - 69.41.191.255

127.0.0.1 2a02:598:2::1095

so i want to clean the old file by removing comments, and duplicates, so far i have 
my @array = ();
$#array = -1;
my @tmp_array = ();
$#tmp_array = -1;
my @uniq = ();
$#uniq = -1;
my $i = 0;
open(HOST_ORIG,'<', $file_read ) or die "Can't open $file_read: $!";
chomp(@array = <HOST_ORIG>);
  foreach $i (4...scalar(@array)-1)
  {
    (my $local_127, $tmp_array[$i] )=split(" ",$array[$i]);
  };
close(HOST_ORIG);

my %seen;
my @uniq = grep {! $seen{$_}++} sort(@tmp_array);
open(TEMP, '>', $file_write)|| die "\n error opening file $file_write 
+\n";
print TEMP "#Hosts file\n";
print TEMP "#Last Modified  -> ". localtime() . "\n";
print TEMP "# \n";
print TEMP "# localhost: Needs to stay like this to work\n";
print TEMP "127.0.0.1\t localhost\n";
print TEMP "# \n";
foreach $i (1...scalar(@uniq)-1)
{
  print TEMP "127.0.0.1\t $uniq[$i]\n";
}
close(TEMP);

[download]

it works except when there are 3 or more columns, the 3rd and 4rth columns get wrapped around to a new line like this

127.0.0.1 c2.gostats.com

#SpySweeper.Spy.Cookie

how do i throw away the rest of the line if it exists?

Thanks!

In reply to parsing a terrible /etc/hosts by f77coder

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