golang 获取NTP服务器时间并自动设置

package main

import (
    "encoding/binary"
    "flag"
    "fmt"
    "log"
    "net"
    "runtime"
    "time"

    "github.com/gogf/gf/os/glog"
    "github.com/gogf/gf/os/gproc"
    "github.com/gogf/gf/text/gstr"
)

const ntpEpochOffset = 2208988800

type packet struct {
    Settings       uint8
    Stratum        uint8
    Poll           int8
    Precision      int8
    RootDelay      uint32
    RootDispersion uint32
    ReferenceID    uint32
    RefTimeSec     uint32
    RefTimeFrac    uint32
    OrigTimeSec    uint32
    OrigTimeFrac   uint32
    RxTimeSec      uint32
    RxTimeFrac     uint32
    TxTimeSec      uint32
    TxTimeFrac     uint32
}

func main() {
    var timeLayoutStr = "2006-01-02 15:04:05"

    ntime := getremotetime()
    ts := ntime.Format(timeLayoutStr) //time转string
    fmt.Print(ts)
    // 2021-08-29 15:53:35.922579627 +0800 CST
    UpdateSystemDate(ts)
}

func getremotetime() time.Time {
    var host string
    // 182.92.12.11:123 是阿里的ntp服务器，可以换成其他域名的
    flag.StringVar(&host, "e", "time.windows.com:123", "NTP host")
    flag.Parse()

    conn, err := net.Dial("udp", host)
    if err != nil {
        log.Fatalf("failed to connect: %v", err)
    }
    defer conn.Close()
    if err := conn.SetDeadline(time.Now().Add(15 * time.Second)); err != nil {
        log.Fatalf("failed to set deadline: %v", err)
    }

    req := &packet{Settings: 0x1B}

    if err := binary.Write(conn, binary.BigEndian, req); err != nil {
        log.Fatalf("failed to send request: %v", err)
    }

    rsp := &packet{}
    if err := binary.Read(conn, binary.BigEndian, rsp); err != nil {
        log.Fatalf("failed to read server response: %v", err)
    }

    secs := float64(rsp.TxTimeSec) - ntpEpochOffset
    nanos := (int64(rsp.TxTimeFrac) * 1e9) >> 32

    showtime := time.Unix(int64(secs), nanos)

    return showtime
}

func UpdateSystemDate(dateTime string) bool {
    system := runtime.GOOS
    switch system {
    case "windows":
        {
            _, err1 := gproc.ShellExec(`date  ` + gstr.Split(dateTime, " ")[0])
            _, err2 := gproc.ShellExec(`time  ` + gstr.Split(dateTime, " ")[1])
            if err1 != nil && err2 != nil {
                glog.Info("更新系统时间错误:请用管理员身份启动程序!")
                return false
            }
            return true

        }
    case "linux":
        {
            _, err1 := gproc.ShellExec(`date -s  "` + dateTime + `"`)
            if err1 != nil {
                glog.Info("更新系统时间错误:", err1.Error())
                return false
            }
            return true
        }
    case "darwin":
        {
            _, err1 := gproc.ShellExec(`date -s  "` + dateTime + `"`)
            if err1 != nil {
                glog.Info("更新系统时间错误:", err1.Error())
                return false
            }
            return true
        }
    }
    return false
}

有疑问加站长微信联系（非本文作者）