I'm not sure what you are trying to do with $count?

$arr[0..$count] = $url =~ /(^http:\/\/.*?)\?(?:([\w\d]*=)(?:.*[&]{1,})
+)*/gi;
[download]

@arr = ($url =~ /(^http:\/\/.*?)\?(?:([\w\d]*=)(?:.*[&]{1,}))*/gi);
[download]

looks more like I think you want although I haven't reviewed your regex in detail. When you put the regex match in a list context, @arr will get all the matches from the /g global match option.