commit https://github.com/vim/vim/commit/4b785f69c0616dba5d3f38e8ce4b5398cec89407 Author: Bram Moolenaar <Bram@vim.org> Date: Tue Nov 29 21:54:44 2016 +0100 patch 8.0.0105 Problem: When using ch_read() with zero timeout, can't tell the difference between reading an empty line and nothing available. Solution: Add ch_canread().

--- a/src/channel.c
+++ b/src/channel.c
@@ -2603,7 +2603,7 @@ channel_is_open(channel_T *channel)
 /*
  * Return TRUE if "channel" has JSON or other typeahead.
  */
-    static int
+    int
 channel_has_readahead(channel_T *channel, ch_part_T part)
 {
     ch_mode_T	ch_mode = channel->ch_part[part].ch_mode;