diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 93efaec..cc19e25 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1087,7 +1087,9 @@
 <	Use 'backupdir' to put the backup in a different directory.
 
 						*'backupskip'* *'bsk'*
-'backupskip' 'bsk'	string	(default: "/tmp/*,$TMPDIR/*,$TMP/*,$TEMP/*")
+'backupskip' 'bsk'	string	(default: "$TMPDIR/*,$TMP/*,$TEMP/*"
+				 Unix: "/tmp/*,$TMPDIR/*,$TMP/*,$TEMP/*"
+				 Mac: "/private/tmp/*,$TMPDIR/*,$TMP/*,$TEMP/*")
 			global
 			{not in Vi}
 			{not available when compiled without the |+wildignore|