C++ 为什么我的 accept() 由于文件描述符错误而失败

我正在制作一个并发的独立于平台的客户端-服务器程序，我的UNIXaccept()由于一个错误的文件描述符而失败，但Winsock运行良好.我在Linux和Windows上对其进行了测试.

int child, len, option = 1, rd;
SOCKET client_socket;
struct sockaddr_in client_addr;

SOCKET server_socket = socket(AF_INET, SOCK_STREAM, 0);
if (server_socket == INVALID_SOCKET)
{
    fprintf(stderr, "Unable to initialize server socket");
    return -1;
}
else printf("Socket successfully created.\n");

if (setsockopt(server_socket, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(int)) == SOCKET_ERROR)
{
    fprintf(stderr, "setsockopt for SO_REUSEADDR failed.\n");
}
else printf("Set SO_REUSEADDR: ON\n");

struct sockaddr_in server_addr;
server_addr.sin_family = AF_INET;
server_addr.sin_addr.s_addr = INADDR_ANY;
server_addr.sin_port = htons(PORT);

if (bind(server_socket, (struct sockaddr *) &server_addr, sizeof(server_addr)) == SOCKET_ERROR)
{
    fprintf(stderr, "Unable to bind to %s port %d\n", inet_ntoa(server_addr.sin_addr), PORT);
    perror("");
    close(server_socket);
    return -1;
}
else printf("Bind successful.\n");

if (listen(server_socket, SOMAXCONN) == SOCKET_ERROR)
{
    fprintf(stderr, "Unable to put server socket into listen state.\n");
    close(server_socket);
    return -1;
}
else printf("Listening on %s:%d.\n", inet_ntoa(server_addr.sin_addr), PORT);
socklen_t cli_addr_size = sizeof(client_addr);

while (true)
{
    //HERE
    client_socket = accept(server_socket, (struct sockaddr *) &client_addr, (socklen_t*) &cli_addr_size);
    if (client_socket == INVALID_SOCKET)
    {
        fprintf(stderr, "Accept failed with %d\n", client_socket);
        perror("");
        return -1;
    }
    else
    {
        printf("Client %s:%d joined the server.\n", inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port));
        child = fork();
        if (child < 0)
        {
            perror("ERROR on fork");
            exit(-1);
        }
        printf("fork() returned %d.\n", child);
        if (child == 0)
        {
            close(server_socket);
            rd = recv(client_socket, rcvbuf, sizeof(rcvbuf), 0);
            if (rd < 0)
                perror("Error in receiving message");
            else if (rd == 0)
                printf("Client %s disconnected\n", inet_ntoa(client_addr.sin_addr));
            else
            {
                sprintf(sndbuf, "Client %s:%d: %s\n", inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port),
                    rcvbuf);
                puts(sndbuf);
                if (send(client_socket, sndbuf, sizeof(sndbuf), 0) < 0)
                {
                    perror("Error in sending message");
                }
            }
        }
    }
}

I have included the chunk of code to prevent guesswork.
Is there also a better way to implement fork() for example by graceful prevention of orphans?
Improvements are welcome.