diff --git a/src/tunnel.zig b/src/tunnel.zig
index c570a83..91260ab 100644
--- a/src/tunnel.zig
+++ b/src/tunnel.zig
@@ -7,7 +7,7 @@ const log = std.log.scoped(.nyotun);
 
 const IFF_TUN = 0x0001; // <linux/if_tun.h>
 const IFF_NO_PI = 0x1000; // <linux/if_tun.h>
-const TUNSETIFF = 0x800454ca; // same value on all archs, see go/src/syscall/*.go
+const TUNSETIFF = 0x400454ca; // compile a C program, run and see
 
 dev: [posix.IFNAMESIZE - 1:0]u8,
 tunFile: posix.fd_t,
@@ -56,7 +56,7 @@ pub fn close(self: *Tunnel) void {
 
 const Tunnel = @This();
 
-test "init tunnel" {
+test "init" {
     var tun = try init("nyotun");
     tun.close();
 }