如题，比如代码这样的：

func command(command string, writer io.Writer, notify chan struct{}) {
r, w := io.Pipe()

cmd := exec.Command("bash")
cmd.Dir = "/data"
cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true} # 这个还不兼容 windows

cmd.Stdin = r

stdout, _ := cmd.StdoutPipe()
stderr, _ := cmd.StderrPipe()
defer stdout.Close()
defer stderr.Close()

cmd.Start()
go trans(stdout, writer) // iocopy
go trans(stderr, writer)

go func() {
<-notify
fmt.Println(cmd.Process.Kill())
w.Close()
}()

fmt.Fprint(w, command)
w.Close()

cmd.Wait()
}