Issue: CLOSED-STREAM-OPERATIONS (Version 1)

[Masinter.pa@Xerox.COM]

This reminds me a little of the PATHNAME issue. I think that CLOSE is only valid
for streams that PATHNAME was valid for

What does it mean to CLOSE a composite stream ( broadcast two-way synonym
concatenated) ? The choices I can think of are:
a) no effect
b) implementation dependent (ugh)
c) closes constituent streams
d) the composite stream is "closed" (no I/O operations allowed) but
	the constituents are not.

What does it mean to close a constructed stream (e.g., STRING)? 
a) no effect
b) implementation dependent (ugh)
c) the constructed stream is "closed" (no I/O operations allowed).


I think the following operations should be as valid after a CLOSE as before
(i.e., they're valid after the close only if they were valid before):

STREAMP, INPUT-STREAM-P, OUTPUT-STREAM-P, TRUENAME, PATHNAME. (In fact, there
are some operating systems where you can *only* get TRUENAME on a closed stream,
since the name isn't true until the stream has been closed.)

Note that the issues STREAM-CAPABILITIES, STREAM-INFO, and  STREAM-CLASS-ACCESS
add functions that take streams.