Fastolfe got you covered for the most part, except, I say, unless you're adding more stuff, there is no need for the quotes at all, meaning $whereto is the same as "$whereto", and unless you're saying "http://$whereto" or some such thing, there is no need for the quotes.

I'd like to know where you got the idea that you needed quotes?

Also, Fastolfe is right that you should use HEAD requests, but apparently a few servers return broken HEAD replies, to which there is a workaround at LWP head replacement.

 
___crazyinsomniac_______________________________________
Disclaimer: Don't blame. It came from inside the void
perl -e "$q=$_;map({chr unpack qq;H*;,$_}split(q;;,q*H*));print;$q/$q;"