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: netlink_linux.go
    path of file: ./repos/kubernetes/vendor/github.com/moby/ipvs
    
    the code of the file until where you have to start completion: package ipvs

import (
	"bytes"
	"encoding/binary"
	"errors"
	"fmt"
	"net"
	"os/exec"
	"strings"
	"sync"

    
func getIPFamily(address []byte) (uint16, error) {
	if len(address) == 4 {
		return syscall.AF_INET, nil
	}

	if isZeros(address) {
		return 0, errors.New("could not parse IP family from address data")
	}

	// assume IPv4 if first 4 bytes are non-zero but rest of the data is trailing zeros
	if !isZeros(address[:4]) && isZeros(address[4:]) {
		return syscall.AF_INET, nil
	}

	return syscall.AF_INET6, nil
}