+(defun imap-id (&optional list-of-values buffer)
+ "Identify client to server in BUFFER, and return server identity.
+LIST-OF-VALUES is nil, or a plist with identifier and value
+strings to send to the server to identify the client.
+
+Return a list of identifiers which server in BUFFER support, or
+nil if it doesn't support ID or returns no information.
+
+If BUFFER is nil, the current buffer is assumed."
+ (with-current-buffer (or buffer (current-buffer))
+ (when (and (imap-capability 'ID)
+ (imap-ok-p (imap-send-command-wait
+ (if (null list-of-values)
+ "ID NIL"
+ (concat "ID (" (mapconcat (lambda (el)
+ (concat "\"" el "\""))
+ list-of-values
+ " ") ")")))))
+ imap-id)))
+