通過 C 中的 curl 下載檔案

#include <stdio.h>
#include <curl/curl.h>

int main (int argc, char *argv[])
{
      CURL *curl;
      CURLcode res;

      /* In windows, this will init the winsock stuff */
      curl_global_init(CURL_GLOBAL_ALL);

      /* get a curl handle */
      curl = curl_easy_init();
      if(curl) {

            printf ("Running curl test.\n");

            struct curl_slist *headers=NULL; /* init to NULL is important */
            headers = curl_slist_append(headers, "Authorization: Bearer <ACCESS_TOKEN>");
            headers = curl_slist_append(headers, "Content-Type:");
            headers = curl_slist_append(headers, "Dropbox-API-Arg: {\"path\":\"/test.txt\"}");
            curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);

            curl_easy_setopt(curl, CURLOPT_URL, "https://content.dropboxapi.com/2/files/download");
            curl_easy_setopt(curl, CURLOPT_POSTFIELDS, "");

            /* Perform the request, res will get the return code */
            res = curl_easy_perform(curl);
            /* Check for errors */
            if(res != CURLE_OK)
                  fprintf(stderr, "curl_easy_perform() failed: %s\n",
                    curl_easy_strerror(res));

            /* always cleanup */
              curl_easy_cleanup(curl);

              printf ("\nFinished curl test.\n");

      }
      curl_global_cleanup();

      printf ("Done!\n");
      return 0;

}

應該用你的訪問令牌替換 <ACCESS_TOKEN>。