In Table [tab:internet.socket.opt.requirements], let C denote a socket option class; let L identify the POSIX macro to be passed as the level argument to POSIX setsockopt and getsockopt; let N identify the POSIX macro to be passed as the option_name argument to POSIX setsockopt and getsockopt; let T identify the type of the value whose address will be passed as the option_value argument to POSIX setsockopt and getsockopt; let p denote a (possibly const) value of a type meeting the protocol ([socket.reqmts.protocol]) requirements, as passed to the socket option's level and name member functions; and let F be the value of p.family().
| C | L | N | T | Requirements, |
| definition or notes | ||||
|
ip::tcp:: no_delay | IPPROTO_TCP | TCP_NODELAY | int | Satisfies the BooleanSocketOption ([socket.reqmts.opt.bool]) type requirements. Determines whether a TCP socket will avoid coalescing of small segments. [ Note: That is, setting this option disables the Nagle algorithm. — end note ] |
| ip::v6_only | IPPROTO_IPV6 | IPV6_V6ONLY | int | Satisfies the BooleanSocketOption ([socket.reqmts.opt.bool]) type requirements. Determines whether a socket created for an IPv6 protocol is restricted to IPv6 communications only. Implementations are not required to support setting the v6_only option to false, and the initial value of the v6_only option for a socket is implementation-defined. [ Note: As not all operating systems support dual stack IP networking. Some operating systems that do provide dual stack support offer a configuration option to disable it or to set the initial value of the v6_only socket option. — end note ] |
| ip::unicast:: hops | IPPROTO_IPV6 if F == AF_INET6, otherwise IPPROTO_IP | IPV6_UNICAST_HOPS if F == AF_INET6, otherwise IP_TTL | int | Satisfies the IntegerSocketOption ([socket.reqmts.opt.int]) type requirements. Specifies the default number of hops (also known as time-to-live or TTL) on outbound datagrams. The constructor and assignment operator for the ip::unicast::hops class throw out_of_range if the int argument is not in the range [0, 255]. |
| ip::multicast:: join_group | IPPROTO_IPV6 if F == AF_INET6, otherwise IPPROTO_IP | IPV6_JOIN_GROUP if F == AF_INET6, otherwise IP_ADD_MEMBERSHIP | ipv6_mreq if F == AF_INET6, otherwise ip_mreq | Satisfies the MulticastGroupSocketOption ([internet.reqmts.opt.mcast]) type requirements. Requests that the socket join the specified multicast group. |
| ip::multicast:: leave_group | IPPROTO_IPV6 if F == AF_INET6, otherwise IPPROTO_IP | IPV6_LEAVE_GROUP if F == AF_INET6, otherwise IP_DROP_MEMBERSHIP | ipv6_mreq if F == AF_INET6, otherwise ip_mreq | Satisfies the MulticastGroupSocketOption ([internet.reqmts.opt.mcast]) type requirements. Requests that the socket leave the specified multicast group. |
| ip::multicast::
outbound_interface ([internet.multicast.outbound]) | IPPROTO_IPV6 if F == AF_INET6, otherwise IPPROTO_IP | IPV6_MULTICAST_IF if F == AF_INET6, otherwise IP_MULTICAST_IF | unsigned int if F == AF_INET6, otherwise in_addr | Specifies the network interface to use for outgoing multicast datagrams. |
| ip::multicast:: hops | IPPROTO_IPV6 if F == AF_INET6, otherwise IPPROTO_IP | IPV6_MULTICAST_HOPS if F == AF_INET6, otherwise IP_MULTICAST_TTL | int | Satisfies the IntegerSocketOption ([socket.reqmts.opt.int]) type requirements. Specifies the default number of hops (also known as time-to-live or TTL) on outbound datagrams. The constructor and assignment operator for the ip::multicast::hops class throw out_of_range if the int argument is not in the range [0, 255]. |
| ip::multicast:: enable_loopback | IPPROTO_IPV6 if F == AF_INET6, otherwise IPPROTO_IP | IPV6_MULTICAST_LOOP if F == AF_INET6, otherwise IP_MULTICAST_LOOP | int | Satisfies the BooleanSocketOption ([socket.reqmts.opt.bool]) type requirements. Determines whether multicast datagrams are delivered back to the local application. |
The outbound_interface class represents a socket option that specifies the network interface to use for outgoing multicast datagrams.
namespace std {
namespace experimental {
namespace net {
inline namespace v1 {
namespace ip {
namespace multicast {
class outbound_interface
{
public:
// constructors:
explicit outbound_interface(const address_v4& network_interface) noexcept;
explicit outbound_interface(unsigned int network_interface) noexcept;
};
} // namespace multicast
} // namespace ip
} // inline namespace v1
} // namespace net
} // namespace experimental
} // namespace std
outbound_interface satisfies the requirements for Destructible (C++ 2014 [destructible]), CopyConstructible (C++ 2014 [copyconstructible]), CopyAssignable (C++ 2014 [copyassignable]), and SettableSocketOption ([socket.reqmts.settablesocketoption]).
Extensible implementations provide the following member functions:
namespace std {
namespace experimental {
namespace net {
inline namespace v1 {
namespace ip {
namespace multicast {
class outbound_interface
{
public:
template<class Protocol> int level(const Protocol& p) const noexcept;
template<class Protocol> int name(const Protocol& p) const noexcept;
template<class Protocol> const void* data(const Protocol& p) const noexcept;
template<class Protocol> size_t size(const Protocol& p) const noexcept;
// remainder unchanged
private:
in_addr v4_value_; // exposition only
unsigned int v6_value_; // exposition only
};
} // namespace multicast
} // namespace ip
} // inline namespace v1
} // namespace net
} // namespace experimental
} // namespace std
explicit outbound_interface(const address_v4& network_interface) noexcept;
Effects: For extensible implementations, v4_value_ is initialized to correspond to the IPv4 address network_interface, and v6_value_ is zero-initialized.
explicit outbound_interface(unsigned int network_interface) noexcept;
Effects: For extensible implementations, v6_value_ is initialized to network_interface, and v4_value_ is zero-initialized.
template<class Protocol> int level(const Protocol& p) const noexcept;
Returns: IPPROTO_IPV6 if p.family() == AF_INET6, otherwise IPPROTO_IP.
template<class Protocol> int name(const Protocol& p) const noexcept;
Returns: IPV6_MULTICAST_IF if p.family() == AF_INET6, otherwise IP_MULTICAST_IF.
template<class Protocol> const void* data(const Protocol& p) const noexcept;
Returns: addressof(v6_value_) if p.family() == AF_INET6, otherwise addressof(v4_value_).
template<class Protocol> size_t size(const Protocol& p) const noexcept;
Returns: sizeof(v6_value_) if p.family() == AF_INET6, otherwise sizeof(v4_value_).