Update runtime files
diff --git a/runtime/doc/userfunc.txt b/runtime/doc/userfunc.txt
index 46bd0c8..0ebc82a 100644
--- a/runtime/doc/userfunc.txt
+++ b/runtime/doc/userfunc.txt
@@ -405,7 +405,7 @@
 	  call Handle('Outfile')
 	endfunc
 
-Note that deleting "Outfile" is scheduled before calling system(), since it
+Note that deleting "Outfile" is scheduled before calling `system()`, since it
 can be created even when `system()` fails.
 
 The deferred functions are called in reverse order, the last one added is