Append to a file in Go

So I can read from a local file like so:

data, error := ioutil.ReadFile(name)

And I can write to a local file

ioutil.WriteFile(filename, content, permission)

But how can I append to a file? Is there a built in method?

This answers works in Go1:

f, err := os.OpenFile(filename, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0600)
if err != nil {
    panic(err)
}

defer f.Close()

if _, err = f.WriteString(text); err != nil {
    panic(err)
}