use LWP::UserAgent;
 use HTTP::Headers;

my $link = "ftp://ftp.uniprot.org/pub/databases/uniprot/current_release/knowledgebase/complete/reldate.txt";

simple_get($link);

sub simple_get {
        my $url = shift;

        use HTTP::Request;
        use LWP::UserAgent;
        my $ua = new LWP::UserAgent;
        my $request = HTTP::Request->new(GET => $url);
        my $response = $ua->request($request);
        my $error = 1 unless ($response->is_success);

        if ($error){
                print "There is an error\n";
        }else{
                print "OK!\n";
        }
}