|  | 
A socket acceptor service must meet the requirements for an I/O object service, as well as the additional requirements listed below.
        In the table below, X denotes
        a socket acceptor 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,
        k denotes a value of type
        basic_socket<Protocol, SocketService>
        where SocketService is a
        type meeting socket service
        requirements, ah denotes
        a value meeting AcceptHandler requirements, and
        u and v
        denote identifiers.
      
Table 29. SocketAcceptorService requirements
| expression | return type | 
                  assertion/note | 
|---|---|---|
| 
                   | 
                  The implementation-defined native representation of a socket acceptor.
                  Must satisfy the requirements of  | |
| 
                   | 
                  From IoObjectService
                  requirements. | |
| 
                   | 
                  From IoObjectService
                  requirements. Implicitly cancels asynchronous operations, as if
                  by calling  | |
| 
 a.move_construct(b, c); 
 | 
                  From IoObjectService
                  requirements. The underlying native representation is moved from
                   | |
| 
 a.move_assign(b, ao, c); 
 | 
                  From IoObjectService
                  requirements. Implicitly cancels asynchronous operations associated
                  with  | |
| 
 a.open(b, p, ec); 
 | 
                   | 
                  pre:  | 
| 
 a.assign(b, p, n, ec); 
 | 
                   | 
                  pre:  | 
| 
 a.is_open(b); 
 | 
                   | |
| 
 const X& u = a; const X::implementation_type& v = b; u.is_open(v); 
 | 
                   | |
| 
 a.close(b, ec); 
 | 
                   | 
                  If  | 
| 
 a.native_handle(b); 
 | 
                   | |
| 
 a.cancel(b, ec); 
 | 
                   | 
                  pre:  | 
| 
 a.set_option(b, s, ec); 
 | 
                   | 
                  pre:  | 
| 
 a.get_option(b, g, ec); 
 | 
                   | 
                  pre:  | 
| 
 const X& u = a; const X::implementation_type& v = b; u.get_option(v, g, ec); 
 | 
                   | 
                  pre:  | 
| 
 a.io_control(b, i, ec); 
 | 
                   | 
                  pre:  | 
| 
 const typename Protocol::endpoint& u = e; a.bind(b, u, ec); 
 | 
                   | 
                  pre:  | 
| 
 a.local_endpoint(b, ec); 
 | 
                   | 
                  pre:  | 
| 
 const X& u = a; const X::implementation_type& v = b; u.local_endpoint(v, ec); 
 | 
                   | 
                  pre:  | 
| 
 a.accept(b, k, &e, ec); 
 | 
                   | 
                  pre:  | 
| 
 a.accept(b, k, 0, ec); 
 | 
                   | 
                  pre:  | 
| 
 a.async_accept(b, k, &e, ah); 
 | 
                  pre:  | |
| 
 a.async_accept(b, k, 0, ah); 
 | 
                  pre:  |