golang exec.Command执行脚本 杀死子进程

package main

import (
    "bytes"
    "os/exec"
    "fmt"
    "context"
    "time"
    "syscall"
)



func main() {
    var (
        cmd *exec.Cmd
        //output []byte
        //err error
    )

    ctx, cancelFunc := context.WithCancel(context.Background())

    go func() {


        // 生成Cmd
        cmd = exec.CommandContext(ctx, "/bin/bash", "-c", "/usr/bin/php ./b.php")

        cmd.SysProcAttr = &syscall.SysProcAttr{}

        var b bytes.Buffer
        cmd.Stdout = &b //剧透，坑在这里
        cmd.Stderr = &b
        if err := cmd.Start(); err != nil {
            fmt.Println(err)
            return
        }



        // 超时杀掉进程组 或正常退出
        go func() {
            select {
            case <-ctx.Done():
                fmt.Println( cmd.Process.Pid)
            }
        }()


        if err := cmd.Wait(); err != nil {
            fmt.Println(err)
            fmt.Println("recive: ", b.String())
            return
        }

        fmt.Println("recive: ", b.String())

    }()
    time.Sleep(time.Second*20)
    cancelFunc()
    fmt.Println(9999999)


    // 打印子进程的输出
    time.Sleep(time.Second*1000)
}

b.php  会运行1500秒后才会停止

<?php

$a = true;
while ($a) {
   for($i=1;$i<=1500;$i++){
       sleep(1);
       if($i == 1500){
            $a = false;
       }
    }
}


echo 5566;


exit;

go run ./main.go

同时查看进程运行状态

ps -aux|grep b.php

[root@serv-test etcd-v3.3.13-linux-amd64]# ps -aux|grep b.php
Warning: bad syntax, perhaps a bogus '-'? See /usr/share/doc/procps-3.2.8/FAQ
root     17758  0.0  0.0 263856 11532 pts/2    S+   16:56   0:00 /usr/bin/php ./b.php
root     18069  0.0  0.0 103340   920 pts/1    S+   16:56   0:00 grep b.php

 当20秒过后 golang程序会停止执行该任务  同时打印出了pid进程号

[root@serv-test golang-test]# go run ./main.go 
开始
9999999
17758
signal: killed

 再次查看pid进程状态 发现进程已经不存在了

[root@serv-test etcd-v3.3.13-linux-amd64]# ps -aux|grep b.php
Warning: bad syntax, perhaps a bogus '-'? See /usr/share/doc/procps-3.2.8/FAQ
root     26397  0.0  0.0 103336   916 pts/1    S+   17:00   0:00 grep b.php