[R6RS] write/read or read/write invariance

[dyb at cs.indiana.edu]

I think I may be confused about what is meant by write/read invariance (or
read/write invariance, if that's what we want and there's a difference).

Can someone explain for me exactly what is intended and how (if) the
current Unicode SRFI draft (i.e., the one committed to the repository)
implements it?

In particular, should the following return #t (assuming that there are no
I/O problems)?

  (let ([x (string->symbol "12345")])
    (with-output-to-file "foo" (lambda () (write x)))
    (eq? (with-input-from-file "foo" read) x))

What will the file foo contain?

Kent