Looks like wget is putting the response code into STDERR. I did this 

$response = `wget --spider -nv $url 2>&1`;

[download]
And got the code into $response.

As for the varying return codes, it probably means that the server you're hitting is not able to respond properly everytime. Maybe it's overloaded, or purposely throttling you. Could be many things.

non-Perl: Andy Ford

In reply to Re: Wget using backquotes by andyford
in thread Wget using backquotes by Anonymous Monk

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