1) Definition of :"random port" should say "must not" (a random port
that returns an eof-object is broken).

2) "Determinize" means "make deterministic" per Wikt.  I suggest
"deterministic", but see my discussion below of an alternative library
structure.

I have moved the rest of this email to
https://codeberg.org/scheme/r7rs/wiki/Alternative-SRFI-271-library-structure.