来自Golang API的Docker exec命令

Need help.I have code to exec command from docker container. Need corrently get stdout from exec command.

execConfig:= types.ExecConfig{Tty:false,AttachStdout:true,AttachStderr:false,Cmd:command}
    respIdExecCreate,err := cli.ContainerExecCreate(context.Background(),dockerName,execConfig)
    if err != nil {
        fmt.Println(err)
    }
    respId,err:=cli.ContainerExecAttach(context.Background(),respIdExecCreate.ID,types.ExecStartCheck{})
    if err != nil {
        fmt.Println(err)
    }
    scanner := bufio.NewScanner(respId.Reader)
    for scanner.Scan() {
       fmt.Println(output)
}

From output i see interesting situation: Screen from gyazo

How corrently remove bytes ?

I send simply command := []string{"echo","-n", "hello word"}