50     virtual Status getsockname(Fd sock, sockaddr* addr, socklen_t* addrlen) const = 0;
52     virtual Status getsockopt(Fd sock, int level, int optname, void *optval,
55     virtual Status setsockopt(Fd sock, int level, int optname, const void* optval,
58     virtual Status bind(Fd sock, const sockaddr* addr, socklen_t addrlen) const = 0;
60     virtual Status connect(Fd sock, const sockaddr* addr, socklen_t addrlen) const = 0;
62     virtual StatusOr<ifreq> ioctl(Fd sock, unsigned long request, ifreq* ifr) const = 0;
68     virtual StatusOr<size_t> writev(Fd fd, const std::vector<iovec>& iov) const = 0;
70     virtual StatusOr<size_t> write(Fd fd, const Slice buf) const = 0;
72     virtual StatusOr<Slice> read(Fd fd, const Slice buf) const = 0;
74     virtual StatusOr<size_t> sendto(Fd sock, const Slice buf, int flags, const sockaddr* dst,
77     virtual StatusOr<Slice> recvfrom(Fd sock, const Slice dst, int flags, sockaddr* src,
80     virtual Status shutdown(Fd fd, int how) const = 0;
82     virtual Status close(Fd fd) const = 0;
117     StatusOr<SockaddrT> getsockname(Fd sock) const {  in getsockname()
125     Status getsockopt(Fd sock, int level, int optname, void* optval, socklen_t* optlen) const {  in getsockopt()
130     Status setsockopt(Fd sock, int level, int optname, const SockoptT& opt) const {  in setsockopt()
135     Status bind(Fd sock, const SockaddrT& addr) const {  in bind()
140     Status connect(Fd sock, const SockaddrT& addr) const {  in connect()
145     StatusOr<std::array<uint16_t, size>> ppoll(const std::array<Fd, size>& fds, uint16_t events,  in ppoll()  argument
162     StatusOr<size_t> sendto(Fd sock, const Slice buf, int flags, const SockaddrT& dst) const {  in sendto()
167     StatusOr<Slice> recvfrom(Fd sock, const Slice dst, int flags) const {  in recvfrom()
172     StatusOr<std::pair<Slice, SockaddrT>> recvfrom(Fd sock, const Slice dst, int flags) const {  in recvfrom()