c++初始化socket并实现TCP连接

要初始化socket并实现TCP连接，需要以下步骤：

1. 引入头文件

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <cstring>
#include <iostream>

2. 创建TCP socket

int client_socket = socket(AF_INET, SOCK_STREAM, 0);

3. 设置服务器地址和端口

struct sockaddr_in server_address;
memset(&server_address, 0, sizeof(server_address));
server_address.sin_family = AF_INET;
server_address.sin_port = htons(port); // port为服务器端口
server_address.sin_addr.s_addr = inet_addr(ip); // ip为服务器IP地址

4. 连接服务器

if (connect(client_socket, (struct sockaddr*)&server_address, sizeof(server_address)) != 0) {
    std::cout << "connect error" << std::endl;
    close(client_socket);
    return -1;
}

完整代码示例：

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <cstring>
#include <iostream>

int main() {
    int client_socket = socket(AF_INET, SOCK_STREAM, 0);
    if (client_socket == -1) {
        std::cout << "create socket error" << std::endl;
        return -1;
    }

    struct sockaddr_in server_address;
    memset(&server_address, 0, sizeof(server_address));
    server_address.sin_family = AF_INET;
    server_address.sin_port = htons(8000);
    server_address.sin_addr.s_addr = inet_addr("127.0.0.1");

    if (connect(client_socket, (struct sockaddr*)&server_address, sizeof(server_address)) != 0) {
        std::cout << "connect error" << std::endl;
        close(client_socket);
        return -1;
    }

    // 连接成功，可以开始进行数据交互

    close(client_socket);
    return 0;
}