Headers when handling response to async request

Question

I'm using cpp-netlib library to create HTTP GET requests, the documentation shows this function call:

response_ = client_.get(request_, callback)

where the signature of callback should be

void(iterator_range<char const *> const &, boost::system::error_code const&)

which allows me to handle the content of the response in chunks. However, this doesn't allow me to get the header information when the callback is executed (which will be in response_, for now I'm interested in the status code). Is there any way to do this?