patch 8.0.0015
Problem:    Can't tell which part of a channel has "buffered" status.
Solution:   Add an optional argument to ch_status().  Let ch_info() also
            return "buffered" for out_status and err_status.
diff --git a/src/proto/channel.pro b/src/proto/channel.pro
index 869989c..e056d5f 100644
--- a/src/proto/channel.pro
+++ b/src/proto/channel.pro
@@ -24,7 +24,7 @@
 int channel_collapse(channel_T *channel, int part, int want_nl);
 int channel_can_write_to(channel_T *channel);
 int channel_is_open(channel_T *channel);
-char *channel_status(channel_T *channel);
+char *channel_status(channel_T *channel, int req_part);
 void channel_info(channel_T *channel, dict_T *dict);
 void channel_close(channel_T *channel, int invoke_close_cb);
 void channel_close_in(channel_T *channel);