doc/protocol.rst: mention that unknown lines may be omitted

2018-11-12 12:57:45 +01:00 · 2018-11-12 12:57:45 +01:00 · 685b78828d
parent 060908d5c4
commit 685b78828d
1 changed files with 4 additions and 0 deletions
--- a/doc/protocol.rst
+++ b/doc/protocol.rst
@ -419,6 +419,10 @@ Querying ``MPD``'s status
    - ``updating_db``: ``job id``
    - ``error``: if there is an error, returns message here

+    :program:`MPD` may omit lines which have no (known) value.  Older
+    :program:`MPD` versions used to have a "magic" value for
+    "unknown", e.g. ":samp:`volume: -1`".
+
 :command:`stats`
    Displays statistics.