> Amaury did not suggest to use openat, but the new opener argument to open, which was especially added for use cases such as the one discussed here:

Sorry, yes. Wrong words, same thought. We can implement this using opener, but we could implement this with os.open before. What's changed, except that there's more ways to do it? (There is slightly more versatility with the opener method, but no more obviousness and no less typing).

My understanding from reading the other thread is that this is not the primary use-case of the new parameter for open(). In fact, this ticket was not really mentioned at all there.