added clarifying comment

                  this syntax. */

  curl_off_t resume_from; /* continue [ftp] transfer from here */

  /* Protocol specific data */

  /* Protocol specific data.

   *

   *************************************************************************

   * Note that this data will be REMOVED after each request, so anything that

   * should be kept/stored on a per-connection basis and thus live for the

   * next requst on the same connection MUST be put in the connectdata struct!

   *************************************************************************/

  union {

    struct HTTP *http;

    struct HTTP *https;  /* alias, just for the sake of being more readable */