golang报socket:operation not permitted

hey，大家好，最近我在看golang基础部分，尝试了《Go语言编程》中关于socket编程，我试验了以下代码，却提示我说Fatal error: dial ip4:icmp 78.216.200.70: socket: operation not permitted,我已经确认ping存在，且已使用chmod将ping权限设置为u+s，我的系统是os x，代码如下:

package main

import (
    "os"
    "fmt"
    "net"
    "bytes"
    "io"
)

func main() {
    if len(os.Args) != 2 {
        fmt.Println("Usage: ", os.Args[0], "host")
        os.Exit(1)
    }
    service := os.Args[1]

    conn, err := net.Dial("ip4:icmp", service)
    checkError(err)

    var msg [512]byte
    msg[0] = 8  // echo
    msg[1] = 0  // code 0
    msg[2] = 0  // checksum
    msg[3] = 0  // checksum
    msg[4] = 0  // identifier[0]
    msg[5] = 13 //identifier[1]
    msg[6] = 0  // sequence[0]
    msg[7] = 37 // sequence[1]

    len := 8

    check := checkSum(msg[0:len])

    msg[2] = byte(check >> 8)
    msg[3] = byte(check & 255)

    _, err = conn.Write(msg[0:len])
    checkError(err)

    _, err = conn.Read(msg[0:])

    fmt.Println("Got response")

    if msg[5] == 13 {
        fmt.Println("Identifier matches")
    }
    if msg[7] == 37 {
        fmt.Println("Sequence matches")
    }
    os.Exit(0)
}

func checkSum(msg []byte) uint16 {
    sum := 0

    for n := 1; n < len(msg)-1; n += 2 {
        sum += int(msg[n])*256 + int(msg[n+1])
    }
    sum = (sum >> 16) + (sum & 0xffff)
    sum += (sum >> 16)
    var answer uint16 = uint16(^sum)
    return answer
}

func readFully(conn net.Conn) ([]byte, error) {
    defer conn.Close()
    result := bytes.NewBuffer(nil)

    var buf [512]byte

    for {
        n, err := conn.Read(buf[0:])
        result.Write(buf[0:n])
        if err != nil {
            if err == io.EOF {
                break
            }
            return nil, err
        }
    }
    return result.Bytes(), nil
}

func checkError(err error) {
    if err != nil {
        fmt.Fprintf(os.Stderr, "Fatal error: %s", err.Error())
    }
    os.Exit(1)
}

请问我这个问题出在哪里呢