int connect (int, const struct sockaddr *, socklen_t);
int listen (int, int);
int accept (int, struct sockaddr *__restrict, socklen_t *__restrict);
+int accept4(int, struct sockaddr *__restrict, socklen_t *__restrict, int);
int getsockname (int, struct sockaddr *__restrict, socklen_t *__restrict);
int getpeername (int, struct sockaddr *__restrict, socklen_t *__restrict);