golang 实现端口扫描

gonet.Dial

func ScanPort(protocol string, hostname string, port int) bool {
	fmt.Printf("scanning port %d \n", port)
	p := strconv.Itoa(port)
	addr := net.JoinHostPort(hostname, p)
	conn, err := net.DialTimeout(protocol, addr, 3*time.Second)
	if err != nil {
		return false
	}
	defer conn.Close()
	return true
}

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