[boost] [asio] Why "const mutable_buffers &" in interfaces?

Hi Just a question asking to clarify the use of "const Mutable_Buffers &mutable_buffers" in the calls to some of the functions, e.g stream_socket::receive(const Mutable_Buffers &buffers, message_flags flags). To me, this is not logical, since I'd expect a receive function to actually modify the stuff I send into it, and the const qualifier doesn't seem to allow this. If it needs to be this way, you might want to explicitly explain this design choice somewhere close to where it is used. Also the reference documentation for asio::mutable_buffer seems to have a copy-paste bug; its detailed description includes "The const_buffer class provides ...", or am I missing something? Mats