[/ / Copyright (c) 2003-2008 Christopher M. Kohlhoff (chris at kohlhoff dot com) / / Distributed under the Boost Software License, Version 1.0. (See accompanying / file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) /] [section:Protocol Protocol requirements] A protocol must meet the requirements of `CopyConstructible` types (C++ Std, 20.1.3), and the requirements of `Assignable` types (C++ Std, 23.1). In the table below, `X` denotes a protocol class, and `a` denotes a value of `X`. [table Protocol requirements [[expression] [return type] [assertion/note\npre/post-conditions]] [ [`X::endpoint`] [type meeting [link boost_asio.reference.Endpoint endpoint] requirements] [] ] [ [`a.family()`] [`int`] [ Returns a value suitable for passing as the /domain/ argument to __POSIX__ __socket__ (or equivalent). ] ] [ [`a.type()`] [`int`] [ Returns a value suitable for passing as the /type/ argument to __POSIX__ __socket__ (or equivalent). ] ] [ [`a.protocol()`] [`int`] [ Returns a value suitable for passing as the /protocol/ argument to __POSIX__ __socket__ (or equivalent). ] ] ] [endsect]