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OPEN for :OUTPUT with version :NEWEST

    Date: Tuesday, 21 June 1983, 17:29-EDT
    From: Daniel L. Weinreb <DLW at SCRC-TENEX>

    The following should be made clear by explicit mention somewhere in 
    the manual:

    Question: If you call OPEN, and the direction is :OUTPUT or :IO, and the
    version of the file is :NEWEST, what version number is used?

    Answer:  If the :IF-EXISTS is :NEW-VERSION or unsupplied, then :NEWEST
    in the pathname means "a version number one higher than the highest
    version extant."  In all other cases :NEWEST in the pathname means "the
    highest extant version."

    So if versions 1, 2, and 3 of a file exist, and you open the :NEWEST
    version for :OUTPUT, then you get version 4 if the :IF-EXISTS is
    :NEW-VERSION or unsupplied, but you get version 3 if the :IF-EXISTS is
    anything else (e.g. :SUPERSEDE, :APPEND, :OVERWRITE, :RENAME, et al).

Perhaps I'm confused, but isn't it the job of the operating system to decide
what the actual filename is? Must the language spec specify "one higher" or
should it just say "newer" or "higher". It seems to me like this wouldn't 
mean any hardship for the users of CL and might make it easier for 
implementors of some CL systems depending on how the operating system they
had treated version numbers (eg, some operating system might not assign a
version until the CLOSE happened).

My worry here is that we be careful about not defining detail where it's
not necessary. I'm not arguing that my position as presented here is right;
just requesting commentary/clarification of your intent.