使用golang将一个shell编输出到另一个awk编

Question

我试图通过golang使用awk，并且我编写了如下程序，但它没有显示输出，也没有显示任何错误。

    package main

    import ("os/exec"
    "fmt"
   )
 func main() {
  app := "tail"
 arg0 := "-n"
 arg1 := "1"
 arg2 := "/var/log/apache2/access.log"
app1 := "awk"
arg5 := "{print $1}"
//arg6 := ">>"
//arg7 := "mem_usage.csv"
  cmd := exec.Command(app, arg0, arg1, arg2)
stdout, err := cmd.StdoutPipe()
//out, err := cmd.Output()
if err != nil {
    fmt.Println(err.Error())
    return
   }

cmd1 := exec.Command(app1, arg5)//, arg6, arg7) 
cmd1.Stdin = stdout
out1,err1 := cmd1.Output()
     if err1 != nil {
    fmt.Println(err1.Error())
    return
    }
    fmt.Println(string(out1))
   //fmt.Println(string(out))
   }