diff --git a/mod.zig b/mod.zig
index 516e18aa75baf29d9a0917477f84dc8633ebfae8..463abe8fde06640828c17e44dce8df31413ebc2d 100644
--- a/mod.zig
+++ b/mod.zig
@@ -2970,6 +2970,7 @@ pub const S = struct {
     pub const IFIFO = 0o010000;
     pub const IFLNK = 0o120000;
     pub const IFSOCK = 0o140000;
+    pub const IFWHT = 0o160000; //unused
 
     pub const ISUID = 0o4000;
     pub const ISGID = 0o2000;