(2/2) Under these conditions, is it possible to create an open fd that behaves like it's open O_WRONLY on /dev/null, and _keeps_ working that way after you exit? ("After you exit" is what that one open local socket is for: this is a thought experiment, but if it was actually a coding challenge, you'd prove you've completed the challenge successfully by sending the fake /dev/null fd to whatever's at the other end of that socket.)