f, err := os.Open(os.DevNull)
		if err != nil {
			return nil, err
		}
		c.childIOFiles = append(c.childIOFiles, f)
		return f, nil
	}

	if f, ok := c.Stdin.(*os.File); ok {
		return f, nil
	}

	pr, pw, err := os.Pipe()
	if err != nil {
		return nil, err
	}

	c.childIOFiles = append(c.childIOFiles, pr)
	c.parentIOPipes = append(c.parentIOPipes, pw)