今天找了好久才找到一篇TFTP原始碼的資料，為了方便以後學習。特別摘錄出來。

這個也許需要引用一些標頭檔案，載入一些lib檔案，在網上找都能找到。

1. TPFTP上傳程式碼 

   static size_t read_callback(void *ptr, size_t size, size_t nmemb, void *stream)
   {
         curl_off_t nread;
   
         /* in real-world cases, this would probably get this data differently
            as this fread() stuff is exactly what the library already would do
            by default internally */
   
         size_t retcode = fread(ptr, size, nmemb, (FILE*)stream);
   
         nread = (curl_off_t)retcode;
   
         fprintf(stderr, "*** We read %" CURL_FORMAT_CURL_OFF_T
                 " bytes from file\n", nread);
   
         return retcode;
   }
   int tftpfileUpload()
   {
         CURL *curl;
         CURLcode res;
         FILE *hd_src;
         struct stat file_info;
         curl_off_t fsize; 
         struct curl_slist *headerlist=NULL;
         static const char buf_1 [] =  UPLOAD_FILE_AS;
         static const char buf_2 [] =  RENAME_FILE_TO;
   
         /* get the file size of the local file */
         if(stat(LOCAL_FILE, &file_info)) {
           printf("Couldnt open '%s': %s\n", LOCAL_FILE, strerror(errno));
           return 1;
         }
   
         fsize = (curl_off_t)file_info.st_size;
         printf("Local file size: %" CURL_FORMAT_CURL_OFF_T " bytes.\n", fsize);
   
         /* get a FILE * of the same file */
         hd_src = fopen(LOCAL_FILE, "rb");
   
         /* In windows, this will init the winsock stuff */
         curl_global_init(CURL_GLOBAL_ALL);
   
         /* get a curl handle */
         curl = curl_easy_init();
   
         if(curl) 
         {
   
               /* we want to use our own read function */
               curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_callback);
   
               /* enable uploading */
               curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
   
               /* specify target */
               curl_easy_setopt(curl,CURLOPT_URL, REMOTE_URL);
   
               /* pass in that last of FTP commands to run after the transfer */
               curl_easy_setopt(curl, CURLOPT_POSTQUOTE, headerlist);
   
               /* now specify which file to upload */
               curl_easy_setopt(curl, CURLOPT_READDATA, hd_src);
   
               /* Set the size of the file to upload (optional).  If you give a *_LARGE
                  option you MUST make sure that the type of the passed-in argument is a
                  curl_off_t. If you use CURLOPT_INFILESIZE (without _LARGE) you must
                  make sure that to pass in a type 'long' argument. */
               curl_easy_setopt(curl, CURLOPT_INFILESIZE_LARGE,
                                (curl_off_t)fsize);
   
               /* Now run off and do what you've been told! */
               res = curl_easy_perform(curl);
   
               /* Check for errors */
               if(res != CURLE_OK)
                 fprintf(stderr, "curl_easy_perform() failed: %s\n",
                         curl_easy_strerror(res));
   
               /* clean up the FTP commands list */
               curl_slist_free_all (headerlist);
   
               /* always cleanup */
               curl_easy_cleanup(curl);
         }
   
         fclose(hd_src); /* close the local file */
         curl_global_cleanup();
   
         return 0;
   }
    
   

   直接呼叫 tftpfileUpload() 就行。

2. TPFTP下載程式碼 

struct TftpFile 
{
      const char *filename;
      FILE *stream;
};

static size_t my_fwrite(void *buffer, size_t size, size_t nmemb,void *stream)
{
      struct TftpFile *out=(struct TftpFile *)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 downloadFileFromServer(int deviceID,char* tftpurl,char*local)
{
     CURL *curl;
     CURLcode res;

     struct TftpFile tftpfile={local,NULL};

     curl_global_init(CURL_GLOBAL_DEFAULT);
     curl = curl_easy_init();

     if(curl) 
    {
           curl_easy_setopt(curl, CURLOPT_URL,tftpurl);
           curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, my_fwrite);
           curl_easy_setopt(curl, CURLOPT_WRITEDATA, &tftpfile);
           curl_easy_setopt(curl, CURLOPT_USE_SSL, CURLUSESSL_ALL);
           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(tftpfile.stream)
           fclose(tftpfile.stream); 

    /* close the local file */
     curl_global_cleanup();

     return 0;
}
 

  直接呼叫downloadFileFromServer（）就行。