Question

美好的一天。所以，我有套接字：

if (WSAStartup(MAKEWORD(2, 2), &this->wsaData) != 0)
    throw(errors::WSASTARTUP);

if ((this->serverSocket = socket(AF_INET, SOCK_STREAM, NULL)) == INVALID_SOCKET)
    throw(errors::SOCKET_CREATING);

this->serverSocketAddr.sin_family = AF_INET;
this->serverSocketAddr.sin_port = htons(this->port);
this->serverSocketAddr.sin_addr.s_addr = INADDR_ANY;

if (bind(this->serverSocket, (sockaddr*)&this->serverSocketAddr, sizeof(this->serverSocketAddr)) == SOCKET_ERROR)
    throw(errors::SOCKET_BINDING);

if (listen(this->serverSocket, SOMAXCONN) == SOCKET_ERROR)
    throw(errors::SOCKET_LISTENING);

u_long mode = 1;

if (ioctlsocket(this->serverSocket, FIONBIO, &mode) == SOCKET_ERROR)
    throw (errors::SOCKET_NONBLOCK);

尝试读取这样的传入消息：

std::string receive(SOCKET s) {
    char buff[BUFF_SIZE];
    int nOfReceivedBytes = 0;
    nOfReceivedBytes = recv(s, buff, BUFF_SIZE, NULL);

    if ((nOfReceivedBytes = recv(s, buff, BUFF_SIZE, NULL)) > 0) {
        printMessage("Number of received bytes: %d\n", nOfReceivedBytes);
    }
    else if (nOfReceivedBytes == 0) {
        printMessage("Connection is closed.\n");
        return "";
    }
    else if (nOfReceivedBytes < 0 && errno != EWOULDBLOCK) {
        printMessage("Receive failed.\n");
        return "";
    }

    if (nOfReceivedBytes < BUFF_SIZE)
        buff[nOfReceivedBytes] = '\0';

    return std::string(buff);
}

当我逐步执行receive()时，我收到了很好的消息而没有任何错误。

但如果我没有调试就这样做，我在这里errno == 1

    else if (nOfReceivedBytes < 0 && errno != EWOULDBLOCK) {
        printMessage("Receive failed.\n");
        return "";
    }

不调用ioctlsocket()就可以了。如何解决？

C ++：如何为非阻塞套接字执行I / O.

0 个答案: