diff --git a/src/testdir/keycode_check.json b/src/testdir/keycode_check.json
index e995bae..868c2a9 100644
--- a/src/testdir/keycode_check.json
+++ b/src/testdir/keycode_check.json
@@ -1 +1 @@
-{"12xterm":{"Space":"20","version":"1b5b3e34313b3335363b3063","C-Tab":"1b5b32373b353b397e","A-Esc":"1b5b32373b333b32377e","C-Space":"1b5b32373b353b33327e","status":"","S-C-I":"1b5b32373b363b37337e","C-I":"1b5b32373b353b3130357e","S-Tab":"1b5b5a","Tab":"09","S-Space":"1b5b32373b323b33327e","A-Tab":"1b5b32373b333b397e","C-Esc":"1b5b32373b353b32377e","protocol":"mok2","A-Space":"1b5b32373b333b33327e","S-Esc":"1b","Esc":"1b"},"2kitty":{"Space":"20","version":"1b5b3e313b343030303b323163","C-Tab":"","A-Esc":"1b5b32373b313175","C-Space":"1b5b33323b3575","status":"1b5b3f3175","S-C-I":"1b5b3130353b3675","C-I":"1b5b3130353b3575","S-Tab":"1b5b393b3275","Tab":"09","S-Space":"20","A-Tab":"1b5b393b313175","C-Esc":"1b5b32373b3575","protocol":"kitty","A-Space":"1b5b33323b313175","S-Esc":"1b5b32373b3275","Esc":"1b5b323775"},"11xterm":{"Space":"20","version":"1b5b3e34313b3335363b3063","C-Tab":"09","A-Esc":"9b00","status":"","S-C-I":"09","C-I":"09","S-Tab":"1b5b5a","Tab":"09","S-Space":"20","A-Tab":"8900","C-Esc":"1b","protocol":"none","A-Space":"a000","S-Esc":"1b","Esc":"1b"}}
+{"12xterm":{"Space":"20","version":"1b5b3e34313b3335363b3063","C-Tab":"1b5b32373b353b397e","A-Esc":"1b5b32373b333b32377e","C-Space":"1b5b32373b353b33327e","status":"","S-C-I":"1b5b32373b363b37337e","C-I":"1b5b32373b353b3130357e","S-Tab":"1b5b5a","Tab":"09","S-Space":"1b5b32373b323b33327e","A-Tab":"1b5b32373b333b397e","C-Esc":"1b5b32373b353b32377e","protocol":"mok2","A-Space":"1b5b32373b333b33327e","S-Esc":"1b","Esc":"1b"},"libvterm":{"Space":"20","version":"1b5b3e303b3130303b3063","C-Tab":"1b5b32373b353b397e","A-Esc":"1b5b32373b333b32377e","C-Space":"1b5b32373b353b33327e","status":"","S-C-I":"1b5b32373b363b37337e","C-I":"1b5b32373b353b3130357e","S-Tab":"1b5b5a","Tab":"09","resource":"","A-Tab":"1b5b32373b333b397e","S-Space":"1b5b32373b323b33327e","C-Esc":"1b5b32373b353b32377e","protocol":"mok2","A-Space":"1b5b32373b333b33327e","S-Esc":"1b","Esc":"1b"},"2kitty":{"Space":"20","version":"1b5b3e313b343030303b323163","C-Tab":"","A-Esc":"1b5b32373b313175","C-Space":"1b5b33323b3575","status":"1b5b3f3175","S-C-I":"1b5b3130353b3675","C-I":"1b5b3130353b3575","S-Tab":"1b5b393b3275","Tab":"09","S-Space":"20","A-Tab":"1b5b393b313175","C-Esc":"1b5b32373b3575","protocol":"kitty","A-Space":"1b5b33323b313175","S-Esc":"1b5b32373b3275","Esc":"1b5b323775"},"11xterm":{"Space":"20","version":"1b5b3e34313b3335363b3063","C-Tab":"09","A-Esc":"9b00","status":"","S-C-I":"09","C-I":"09","S-Tab":"1b5b5a","Tab":"09","S-Space":"20","A-Tab":"8900","C-Esc":"1b","protocol":"none","A-Space":"a000","S-Esc":"1b","Esc":"1b"}}
diff --git a/src/testdir/keycode_check.vim b/src/testdir/keycode_check.vim
index de15180..d754490 100644
--- a/src/testdir/keycode_check.vim
+++ b/src/testdir/keycode_check.vim
@@ -319,10 +319,10 @@
     ch_logfile('keylog-ignore', 'a')
     while 1
       sleep 100m
-      if !getchar(1)
+      if getchar(1) == 0
 	break
       endif
-      while getchar(1)
+      while getchar(1) != 0
 	getchar()
       endwhile
     endwhile