use strict;
use LWP::UserAgent;

my $ua = LWP::UserAgent->new;
my $uri = shift @ARGV;
my $headreq = HTTP::Request->new(HEAD => $uri);        
my $headres = $ua->request($headreq);        
my $statuscode = $headres->code();        
print "Status 401 at $uri\n" if $statuscode == 401;