libcurl异步调用

int main(int argc, char **argv)
{
// 初始化
curl_global_init(CURL_GLOBAL_WIN32);
CURLM *multi_handle = NULL;
CURL *easy_handle1 = NULL;
CURL *easy_handle2 = NULL;
extern size_t save_sina_page(void *buffer, size_t size, size_t count, void *user_p);
extern size_t save_sohu_page(void *buffer, size_t size, size_t count, void *user_p);
FILE *fp_sina = fopen("sina.html", "ab+");
FILE *fp_sohu = fopen("sohu.html", "ab+");
multi_handle = curl_multi_init();
// 设置easy handle
easy_handle1 = curl_easy_init();
curl_easy_setopt(easy_handle1, CURLOPT_URL, "http://www.sina.com.cn");
curl_easy_setopt(easy_handle1, CURLOPT_WRITEFUNCTION, &save_sina_page);
curl_easy_setopt(easy_handle1, CURLOPT_WRITEDATA, fp_sina);
easy_handle2 = curl_easy_init();
curl_easy_setopt(easy_handle2, CURLOPT_URL, "http://www.sohu.com");
curl_easy_setopt(easy_handle2, CURLOPT_WRITEFUNCTION, &save_sohu_page);
curl_easy_setopt(easy_handle2, CURLOPT_WRITEDATA, fp_sohu);
// 添加到multi stack
curl_multi_add_handle(multi_handle, easy_handle1);
curl_multi_add_handle(multi_handle, easy_handle2);
//
int running_handle_count;
while (CURLM_CALL_MULTI_PERFORM == curl_multi_perform(multi_handle, &running_handle_count))
{
cout << running_handle_count << endl;
}
while (running_handle_count)
{
timeval tv;
tv.tv_sec = 1;
tv.tv_usec = 0;
int max_fd;
fd_set fd_read;
fd_set fd_write;
fd_set fd_except;
FD_ZERO(&fd_read);
FD_ZERO(&fd_write);
FD_ZERO(&fd_except);
curl_multi_fdset(multi_handle, &fd_read, &fd_write, &fd_except, &max_fd);
int return_code = select(max_fd + 1, &fd_read, &fd_write, &fd_except, &tv);
if (SOCKET_ERROR == return_code)
{
cerr << "select error." << endl;
break;
}
else
{
while (CURLM_CALL_MULTI_PERFORM == curl_multi_perform(multi_handle, &running_handle_count))
{
cout << running_handle_count << endl;
}
}
}
// 释放资源
fclose(fp_sina);
fclose(fp_sohu);
curl_easy_cleanup(easy_handle1);
curl_easy_cleanup(easy_handle2);
curl_multi_cleanup(multi_handle);
curl_global_cleanup();
return 0;
}
size_t save_sina_page(void *buffer, size_t size, size_t count, void *user_p)
{
return fwrite(buffer, size, count, (FILE *)user_p);
}
size_t save_sohu_page(void *buffer, size_t size, size_t count, void *user_p)
{
return fwrite(buffer, size, count, (FILE *)user_p);
}

参考链接:
https://blog.csdn.net/zengraoli/article/details/11580167