You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: tun_darwin.go
    path of file: ./repos/sliver/vendor/github.com/tailscale/wireguard-go/tun
    
    the code of the file until where you have to start completion: /* SPDX-License-Identifier: MIT
 *
 * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
 */

package tun

import (
	"errors"
	"fmt"
	"io"
	"net"
	"os"
	"sync"
	"syscall"
	"time"
	"unsafe"

	"golang.org/x/sys/unix"
)

const utunControlName = "com.appl
    
func (tun *NativeTun) Read(bufs [][]byte, sizes []int, offset int) (int, error) {
	// TODO: the BSDs look very similar in Read() and Write(). They should be
	// collapsed, with platform-specific files containing the varying parts of
	// their implementations.
	select {
	case err := <-tun.errors:
		return 0, err
	default:
		buf := bufs[0][offset-4:]
		n, err := tun.tunFile.Read(buf[:])
		if n < 4 {
			return 0, err
		}
		sizes[0] = n - 4
		return 1, err
	}
}