不是吧 如果多几个过滤，岂不好多重复代码

@lovecn 如果你有更好的 记得回我哦

async

func async() {
    cmd1 := exec.Command("ls", ".")
    cmd2 := exec.Command("grep", "go")
    cmd2.Stdout = os.Stdout
    { // 这部分代码可以封装
        out, _ := cmd1.StdoutPipe()
        in, _ := cmd2.StdinPipe()
        go func() {
            defer func() {
                out.Close()
                in.Close()
            }()
            io.Copy(in, out)
        }()
    }
    cmd1.Run()
    cmd2.Run()
}

sync

func sync() {
    cmd1 := exec.Command("ps", "aux")
    cmd2 := exec.Command("grep", "mysql")
    in, _ := cmd2.StdinPipe()
    cmd1.Stdout = in
    cmd2.Stdout = os.Stdout
    cmd2.Start()
    cmd1.Run()
    in.Close()
    cmd2.Wait()
}

For more

func main() {
    cmd1 := exec.Command("ls", ".")
    cmd2 := exec.Command("grep", "go")
    cmd3 := exec.Command("grep", "main")
    cmd3.Stdout = os.Stdout
    pipe(cmd1, cmd2, cmd3)
    cmd1.Run()
    cmd2.Run()
    cmd3.Run()
}

func pipe(cmds ...*exec.Cmd) {
    for i, cmd := range cmds {
        if i > 0 {
            out, _ := cmds[i-1].StdoutPipe()
            in, _ := cmd.StdinPipe()
            go func() {
                defer func() {
                    out.Close()
                    in.Close()
                }()
                io.Copy(in, out)
            }()
        }
    }
}