Update runtime files
diff --git a/runtime/doc/channel.txt b/runtime/doc/channel.txt
index 39cb43c..6124a89 100644
--- a/runtime/doc/channel.txt
+++ b/runtime/doc/channel.txt
@@ -1,4 +1,4 @@
-*channel.txt*      For Vim version 8.2.  Last change: 2020 Oct 17
+*channel.txt*      For Vim version 8.2.  Last change: 2021 Nov 28
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -101,7 +101,7 @@
 when opening the channel: >
 	call ch_close(channel)
 	let channel = ch_open('localhost:8765', {'callback': "MyHandler"})
-	call ch_sendexpr(channel, 'hello!')
+	call ch_sendexpr(channel, 'hello channel!')
 
 When trying out channels it's useful to see what is going on.  You can tell
 Vim to write lines in log file: >
@@ -132,8 +132,9 @@
 	"raw"  - Use raw messages
 						*channel-callback* *E921*
 "callback"	A function that is called when a message is received that is
-		not handled otherwise.  It gets two arguments: the channel
-		and the received message. Example: >
+		not handled otherwise (e.g. a JSON message with ID zero).  It
+		gets two arguments: the channel and the received message.
+		Example: >
 	func Handle(channel, msg)
 	  echo 'Received: ' . a:msg
 	endfunc