捲曲下載的文件總是空

Question

我嘗試下面的例子後捲曲複製文件：

CURL *curl; 
FILE *fp; 
CURLcode res; 
char *url = "http://localhost/aaa.txt"; 
char outfilename[FILENAME_MAX] = "D:\\bbb.txt"; 

curl = curl_easy_init(); 

if(curl) 
{ 
    fp = fopen(outfilename,"wb"); 
    curl_easy_setopt(curl, CURLOPT_URL, url); 
    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data); 
    curl_easy_setopt(curl, CURLOPT_WRITEDATA, fp); 
    fclose(fp); 
} 

它創建了一個名爲bbb.txt文件，但該文件是空的。願你能幫助我嗎？我的錯誤是什麼？

Answer 1

您錯過了撥打電話curl_easy_perform。看到它的API description。