+yajl_gen ipc_marshal_workspace_event(const char *change, Con *current, Con *old);
+
+/**
+ * For the workspace events we send, along with the usual "change" field, also
+ * the workspace container in "current". For focus events, we send the
+ * previously focused workspace in "old".
+ */
+void ipc_send_workspace_event(const char *change, Con *current, Con *old);