I've merged the SRFI and hga repos into johnwcowan, so please grab it. After a few days I'll do a PR against the SRFI repo.
I've also added (my view of) parent-pid, process-group, user-info:full-name, user-info:parsed-full-name (this shouldn't be a standalone procedure because it needs access to user-info:name), and terminal stuff. Without-interrupt-chars is gone; I don't think it's needed, just raw, cooked, and no-echo. I also changed "tty" to "terminal" everywhere except in the names of Posix functions.