Socket service requirements

A socket service must meet the requirements for an I/O object service with support for movability, as well as the additional requirements listed below.

In the table below, X denotes a socket service class for protocol Protocol, a and ao denote values of type X, b and c denote values of type X::implementation_type, p denotes a value of type Protocol, n denotes a value of type X::native_handle_type, e denotes a value of type Protocol::endpoint, ec denotes a value of type error_code, s denotes a value meeting SettableSocketOption requirements, g denotes a value meeting GettableSocketOption requirements, i denotes a value meeting IoControlCommand requirements, h denotes a value of type socket_base::shutdown_type, ch denotes a value meeting ConnectHandler requirements, and u and v denote identifiers.

Table 30. SocketService requirements

expression	return type	assertion/note pre/post-condition
`X::native_handle_type`		The implementation-defined native representation of a socket. Must satisfy the requirements of `CopyConstructible` types (C++ Std, 20.1.3), and the requirements of `Assignable` types (C++ Std, 23.1).
`a.construct(b);`		From IoObjectService requirements. post: `!a.is_open(b)`.
`a.destroy(b);`		From IoObjectService requirements. Implicitly cancels asynchronous operations, as if by calling `a.close(b, ec)`.
a.move_construct(b, c);		From IoObjectService requirements. The underlying native representation is moved from `c` to `b`.
a.move_assign(b, ao, c);		From IoObjectService requirements. Implicitly cancels asynchronous operations associated with `b`, as if by calling `a.close(b, ec)`. Then the underlying native representation is moved from `c` to `b`.
a.open(b, p, ec);	`error_code`	pre: `!a.is_open(b)`. post: `!!ec \|\| a.is_open(b)`.
a.assign(b, p, n, ec);	`error_code`	pre: `!a.is_open(b)`. post: `!!ec \|\| a.is_open(b)`.
a.is_open(b);	`bool`
const X& u = a; const X::implementation_type& v = b; u.is_open(v);	`bool`
a.close(b, ec);	`error_code`	If `a.is_open()` is true, causes any outstanding asynchronous operations to complete as soon as possible. Handlers for cancelled operations shall be passed the error code `error::operation_aborted`. post: `!a.is_open(b)`.
a.native_handle(b);	`X::native_handle_type`
a.cancel(b, ec);	`error_code`	pre: `a.is_open(b)`. Causes any outstanding asynchronous operations to complete as soon as possible. Handlers for cancelled operations shall be passed the error code `error::operation_aborted`.
a.set_option(b, s, ec);	`error_code`	pre: `a.is_open(b)`.
a.get_option(b, g, ec);	`error_code`	pre: `a.is_open(b)`.
const X& u = a; const X::implementation_type& v = b; u.get_option(v, g, ec);	`error_code`	pre: `a.is_open(b)`.
a.io_control(b, i, ec);	`error_code`	pre: `a.is_open(b)`.
a.at_mark(b, ec);	`bool`	pre: `a.is_open(b)`.
const X& u = a; const X::implementation_type& v = b; u.at_mark(v, ec);	`bool`	pre: `a.is_open(b)`.
a.available(b, ec);	`size_t`	pre: `a.is_open(b)`.
const X& u = a; const X::implementation_type& v = b; u.available(v, ec);	`size_t`	pre: `a.is_open(b)`.
const typename Protocol::endpoint& u = e; a.bind(b, u, ec);	`error_code`	pre: `a.is_open(b)`.
a.shutdown(b, h, ec);	`error_code`	pre: `a.is_open(b)`.
a.local_endpoint(b, ec);	`Protocol::endpoint`	pre: `a.is_open(b)`.
const X& u = a; const X::implementation_type& v = b; u.local_endpoint(v, ec);	`Protocol::endpoint`	pre: `a.is_open(b)`.
a.remote_endpoint(b, ec);	`Protocol::endpoint`	pre: `a.is_open(b)`.
const X& u = a; const X::implementation_type& v = b; u.remote_endpoint(v, ec);	`Protocol::endpoint`	pre: `a.is_open(b)`.
const typename Protocol::endpoint& u = e; a.connect(b, u, ec);	`error_code`	pre: `a.is_open(b)`.
const typename Protocol::endpoint& u = e; a.async_connect(b, u, ch);		pre: `a.is_open(b)`. Initiates an asynchronous connect operation that is performed via the `io_service` object `a.get_io_service()` and behaves according to asynchronous operation requirements.