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