accept4
int accept4(int, struct sockaddr * __restrict, socklen_t * __restrict, int);
RL(saccept = accept4(slisten, /*addr*/NULL, /*addrlen*/NULL,
RL(saccept = accept4(slisten, /*addr*/NULL, /*addrlen*/NULL,
RL(accept4(sock, NULL, NULL, O_CLOEXEC));
acpt = accept4(srvr, NULL, NULL,
acpt = accept4(srvr, NULL, NULL,
connfd = accept4(s, (struct sockaddr *)&cliaddr,