open(F, $ARGV[0]) or
  die "Couldn't open file\n";
print sort by_ip <F>;
close(F);

sub by_ip {
  my ($aip) = split /,/, $a;
  my ($bip) = split /,/, $b;
  
  my ($aa, $ab, $ac, $ad) = split /\./, $aip;
  my ($ba, $bb, $bc, $bd) = split /\./, $bip;
  
  return ($aa <=> $ba) || ($ab <=> $bb) || ($ac <=> $bc) || ($ad <=> $bd);
}

sub by_country {
  my ($ac) = (split /,/, $a)[2];
  my ($bc) = (split /,/, $b)[2];

  return ($ac cmp $bc);
}