Go 使用os.exec（）执行3个或更多命令？

如何在Go（例如ls | grep | wc）中将3+个命令连接在一起？我试图修改这段用于piping 2命令的代码，但无法找到正确的方法

package main

import (
    "os"
    "os/exec"
)

func main() {
    c1 := exec.Command("ls")
    c2 := exec.Command("wc", "-l")
    c2.Stdin, _ = c1.StdoutPipe()
    c2.Stdout = os.Stdout
    _ = c2.Start()
    _ = c1.Run()
    _ = c2.Wait()
}

可能存在的副本

package main

import (
    "os"
    "os/exec"
)

func main() {
    c1 := exec.Command("ls")
    c2 := exec.Command("grep", "-i", "o")
    c3 := exec.Command("wc", "-l")
    c2.Stdin, _ = c1.StdoutPipe()
    c3.Stdin, _ = c2.StdoutPipe()
    c3.Stdout = os.Stdout
    _ = c3.Start()
    _ = c2.Start()
    _ = c1.Run()
    _ = c2.Wait()
    _ = c3.Wait()
}