Hello, I am trying to figure out how to convert an "external relative path" to an absolute one: I'd really like a function that will do the following:

$path = "/search?q=query";
$host = "http://google.com";
$abspath = reltoabs($host, $path);

And have $abspath equal to "http://google.com/search?q=query" The problem is that it is not guaranteed to be in that format, and it could already be absolute, or be pointing to a different host entirely, and I'm not quite sure how to approach this. Thanks.