golang: exec 时继承父级进程数据

main.go

package main

import (
	"fmt"
	"golang.org/x/sys/unix"
	"os"
	"os/exec"
	"syscall"
)

var isRerun = make(map[string]int)

func Self() string {
	return "/proc/self/exe"
}

func Command(args ...string) *exec.Cmd {
	return &exec.Cmd{
		Path: Self(),
		Args: args,
		SysProcAttr: &syscall.SysProcAttr{
			Pdeathsig: unix.SIGTERM,
		},
	}
}

func main() {
	// 注册
	if _, exists := isRerun["flag"]; !exists {
		isRerun["flag"] = 1
	}

	// 当前的名称不叫 flag 所以是 exists=false
	fmt.Println("获取当前的flag", os.Args[0])
	_, exists := isRerun[os.Args[0]]
	if exists {
		fmt.Printf("sec run: %s: pid is %d\n", os.Args[0], os.Getpid())
		fmt.Println("goodbye")
		os.Exit(0)
	} else {
		fmt.Printf("first run: %s: pid is %d\n", os.Args[0], os.Getpid())
	}
	cmd := Command("flag")
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr
	cmd.Run()
}