getsockname始终返回协议族0的结构

Question

getsockname似乎总是用{family}设置为0的结构填充storage，这表示未指定协议。

void print_address_attached_to_socket(int socket) {
    socklen_t socket_length;
    struct sockaddr_storage storage;
    int returncode = getsockname(socket, (struct sockaddr *) (&storage), &socket_length);
    if (returncode != 0) {
        perror("Errror getting sock name");
        exit(1);
    }
    if (storage.ss_family == 0) {
        std::cout << "Family is unspecified getsockname failed without telling why..." << std::endl;
        return;
    } else {
        struct sockaddr *sock_addr = (struct sockaddr *) &storage;
        char host[128] = {0}, serv[128] = {0};
        returncode = getnameinfo(sock_addr, socket_length, host, 128, serv, 128, NI_NUMERICHOST | NI_NUMERICSERV);
        if (returncode != 0) {
            printf("Errror getting resolving name");
            exit(1);
        }
        std::cout << "Host: " << host << ":" << std::endl;
    }
}

在连接之后和关闭之前调用此函数。

用法示例：https://gist.github.com/Hajto/09058b335b2466033f96a9a1adfebef4 client.cpp：调用上面片段的代码，该片段应该获取有关连接到套接字的主机的信息 server.cpp：由于使用了该代码，因此在客户端中使用了该代码，我还附加了服务器以启用运行该客户端。