chore(tun): not linux or not darwin tagged files

internal/tun/check.go

@@ -1,3 +1,5 @@
+//go:build linux || darwin
+
 package tun
 
 import (

internal/tun/check_unspecified.go

@@ -0,0 +1,7 @@
+//go:build !linux && !darwin
+
+package tun
+
+func (t *Tun) Check(path string) error {
+	panic("not implemented")
+}

internal/tun/create.go

@@ -1,3 +1,5 @@
+//go:build linux || darwin
+
 package tun
 
 import (
@@ -20,7 +22,7 @@ func (t *Tun) Create(path string) error {
 		minor = 200
 	)
 	dev := unix.Mkdev(major, minor)
-	err := t.mknod(path, unix.S_IFCHR, int(dev))
+	err := unix.Mknod(path, unix.S_IFCHR, int(dev))
 	if err != nil {
 		return fmt.Errorf("creating TUN device file node: %w", err)
 	}

internal/tun/create_unspecified.go

@@ -0,0 +1,8 @@
+//go:build !linux && !darwin
+
+package tun
+
+// Create creates a TUN device at the path specified.
+func (t *Tun) Create(path string) error {
+	panic("not implemented")
+}

internal/tun/tun.go

@@ -1,13 +1,7 @@
 package tun
 
-import "golang.org/x/sys/unix"
-
-type Tun struct {
-	mknod func(path string, mode uint32, dev int) (err error)
-}
+type Tun struct{}
 
 func New() *Tun {
-	return &Tun{
-		mknod: unix.Mknod,
-	}
+	return &Tun{}
 }

internal/tun/tun_test.go

@@ -1,3 +1,5 @@
+//go:build linux || darwin
+
 package tun
 
 import (