text: /***************************************************************************
   *                                  _   _ ____  _
   *  Project                     ___| | | |  _ \| |
   *                             / __| | | | |_) | |
   *                            | (__| |_| |  _ <| |___
   *                             \___|\___/|_| \_\_____|
   *
   * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
   *
   * This software is licensed as described in the file COPYING, which
   * you should have received as part of this distribution. The terms
   * are also available at https://curl.haxx.se/docs/copyright.html.
   *
   * You may opt to use, copy, modify, merge, publish, distribute and/or sell
   * copies of the Software, and permit persons to whom the Software is
   * furnished to do so, under the terms of the COPYING file.
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
   * KIND, either express or implied.
   *
   ***************************************************************************/
  #include <stdio.h>
  
  #include <curl/curl.h>
  
  /* <DESC>
   * Get a single file from an FTP server.
   * </DESC>
   */
  
  struct FtpFile {
    const char *filename;
    FILE *stream;
  };
  
  static size_t my_fwrite(void *buffer, size_t size, size_t nmemb, void *stream)
  {
    struct FtpFile *out = (struct FtpFile *)stream;
    if(out && !out->stream) {
      /* open file for writing */
      out->stream = fopen(out->filename, "wb");
      if(!out->stream)
        return -1; /* failure, can't open file to write */
    }
    return fwrite(buffer, size, nmemb, out->stream);
  }
  
  
  int main(void)
  {
    CURL *curl;
    CURLcode res;
    struct FtpFile ftpfile = {
      "d:/002.md", /* name to store the file as if successful */
  //    "curl.tar.gz", /* name to store the file as if successful */
      NULL
    };
  
    curl_global_init(CURL_GLOBAL_DEFAULT);
  
    curl = curl_easy_init();
    if(curl) {
      /*
       * You better replace the URL with one that works!
       */
      curl_easy_setopt(curl, CURLOPT_URL,
                       "ftp://ftp.gnu.org/gnu/button.14.0.shar");
  //                     "ftp://ftp.example.com/curl/curl-7.9.2.tar.gz");
      /* Define our callback to get called when there's data to be written */
      curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, my_fwrite);
      /* Set a pointer to our struct to pass to the callback */
      curl_easy_setopt(curl, CURLOPT_WRITEDATA, &ftpfile);
  
      /* Switch on full protocol/debug output */
      curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
  
      res = curl_easy_perform(curl);
  
      /* always cleanup */
      curl_easy_cleanup(curl);
  
      if(CURLE_OK != res) {
        /* we failed */
        fprintf(stderr, "curl told us %d\n", res);
      }
    }
  
    if(ftpfile.stream)
      fclose(ftpfile.stream); /* close the local file */
  
    curl_global_cleanup();
  
    return 0;
  }
  