I'm having a hard time making it fail. Even with Printf, in the output it tells you what you did wrong instead of returning an error.

In fact, the only _print function I could get to fail was Fprintf by sending an already closed file. I suppose if it was somehow not allowed to write to stdout the other functions might fail. But I'm not sure.

    _, err := fmt.Printf("Hello %d", "world")
    fmt.Println(err)
    
    >> Hello %!d(string=world)
    >> <nil>