c/c++语言利用socket编程获取网络上天气预报全部代码

以下是一个简单的示例，演示了如何使用C++和socket编程从网站获取天气预报数据：

#include <iostream>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <unistd.h>

int main(int argc, char *argv[])
{
    struct addrinfo hints, *res, *p;
    int sockfd;

    memset(&hints, 0, sizeof hints);
    hints.ai_family = AF_UNSPEC;
    hints.ai_socktype = SOCK_STREAM;

    if (argc != 2) {
        std::cerr << "Usage: weatherforecast hostname" << std::endl;
        return 1;
    }

    int status = getaddrinfo(argv[1], "80", &hints, &res);
    if (status != 0) {
        std::cerr << "getaddrinfo error: " << gai_strerror(status) << std::endl;
        return 2;
    }

    for (p = res; p != NULL; p = p->ai_next) {
        sockfd = socket(p->ai_family, p->ai_socktype, p->ai_protocol);
        if (sockfd == -1) {
            std::cerr << "socket error" << std::endl;
            continue;
        }

        if (connect(sockfd, p->ai_addr, p->ai_addrlen) == -1) {
            close(sockfd);
            std::cerr << "connect error" << std::endl;
            continue;
        }

        break;
    }

    if (p == NULL) {
        std::cerr << "failed to connect" << std::endl;
        return 3;
    }

    freeaddrinfo(res);

    const char *request = "GET / HTTP/1.1\r\nHost: %s\r\nConnection: close\r\n\r\n";
    char buffer[1024];
    sprintf(buffer, request, argv[1]);
    send(sockfd, buffer, strlen(buffer), 0);

    int bytes_received;
    while ((bytes_received = recv(sockfd, buffer, 1024, 0)) > 0) {
        buffer[bytes_received] = '\0';
        std::cout << buffer;
    }

    close(sockfd);

    return 0;
}

以上代码可以连接到指定的主机并发送HTTP GET请求，并将响应打印到控制台上。你可以将主机名替换为你要访问的天气预报网站的主机名，并根据需要更改请求的格式。