func: static int ftp_file_size(FTPContext *s)
  
  {
  
      char command[CONTROL_BUFFER_SIZE];
  
      char *res = NULL;
  
      const int size_codes[] = {213, 0};
  
  
  
      snprintf(command, sizeof(command), "SIZE %s\r\n", s->path);
  
      if (ftp_send_command(s, command, size_codes, &res)) {
  
          s->filesize = strtoll(&res[4], NULL, 10);
  
      } else {
  
          s->filesize = -1;
  
          av_free(res);
  
          return AVERROR(EIO);
  
      }
  
  
  
      av_free(res);
  
      return 0;
  
  }
  