That's correct. Even with the http:// prefix as
derby suggested, the modified time isn't passed back. Your code is fine, you just need to check if the values are defined.
use LWP::Simple;
use warnings;
use strict;
my $url = 'http://www.perl.com';
my $content = get($url);
my (@header) = head($url);
print "content type: $header[0]\n" if defined $header[0];
print "document length: $header[1]\n" if defined $header[1];
print "modified time: $header[2]\n" if defined $header[2];
print "expires: $header[3]\n" if defined $header[3];
print "server: $header[4]\n" if defined $header[4];
