GET HTTP Response Headers as Array.

response_headers_list.pl

#!/usr/bin/perl
use strict;
use warnings;
use LWP::UserAgent;

my $ua = LWP::UserAgent->new;
$ua->agent("Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:20.0) Gecko/20100101 Firefox/20.0");
my $req = HTTP::Request->new(GET => 'http://www.example.com/');
my $res = $ua->simple_request($req);

my @header_names = $res->headers->header_field_names;
foreach my $header_name (@header_names) {
  print $header_name . ": " . $res->headers->header($header_name) . "\n";
}