nntp.el (nntp-finish-retrieve-group-infos): Protect against the first part not returning any data.

proto-stream.el (open-protocol-stream): Document the return value.

lisp/gnus/ChangeLog

+2011-02-06  Lars Ingebrigtsen  <larsi@gnus.org>
+
+	* nntp.el (nntp-finish-retrieve-group-infos): Protect against the first
+	part not returning any data.
+
+	* proto-stream.el (open-protocol-stream): Document the return value.
+
 2011-02-06  Julien Danjou  <julien@danjou.info>
 	* message.el (message-setup-1): Handle message-generate-headers-first

lisp/gnus/nntp.el

@@ -781,7 +781,8 @@ command whose response triggered the error."
       ;; The first time this is run, this variable is `try'.  So we
       ;; try.
       (when (eq nntp-server-list-active-group 'try)
-	(nntp-try-list-active (gnus-group-real-name (gnus-info-group (car infos)))))
+	(nntp-try-list-active
+	 (gnus-group-real-name (gnus-info-group (car infos)))))
       (with-current-buffer (nntp-find-connection-buffer nntp-server-buffer)
 	(erase-buffer)
 	(let ((nntp-inhibit-erase t)
@@ -800,7 +801,8 @@ command whose response triggered the error."
 		   (car infos)))
 	  (received 0)
 	  (last-point 1))
-      (when buf
+      (when (and buf
+		 count)
 	(with-current-buffer buf
 	  (while (and (gnus-buffer-live-p buf)
 		      (progn

lisp/gnus/proto-stream.el

@@ -94,7 +94,15 @@ query server for capabilities.  For instance, for IMAP this is
 :starttls-function -- a function that takes one parameter, which
 is the response to the capaibility command.  It should return nil
 if it turns out that the server doesn't support STARTTLS, or the
-command to switch on STARTTLS otherwise."
+command to switch on STARTTLS otherwise.
+
+The return value from this function is a four-element list, where
+the first element is the stream (if connection was successful);
+the second element is the \"greeting\", i. e., the string the
+server sent over on initial contact; the third element is the
+capability string; and the fourth element is either `network' or
+`tls', depending on whether the connection ended up being
+encrypted or not."
   (let ((type (or (cadr (memq :type parameters)) 'network)))
     (cond
      ((eq type 'starttls)