Yet, in another discussion, I got the impression that when you say
"ps", what you really mean is "postscript version 1 as defined only by
the 1985 book", and that if I wanted to use Postscript version 2, I'd
have to use a different content
-type marker, e.g., "ps2" or "gif94b".
I don't think you can have it both ways. Could you please clarify what
you intend?
When you say something is application/postscript, you're saying absolutely
nothing about whether it is level 1, level 2, some intermediate level
(which will be by far the most common case soon), or some to-be-specified
level in the future. All this can be specified internally to the PostScript
object itself.
We probably should reference both the level 1 and 2 books, and I will in fact
see about adding such a reference to the new book.
Please note that the level 2 book says a great deal about backwards
compatibility and how to the as much of it as is possible. Please read the
book if you want the details; I'm not going to post the dozens of special-case
rules for this here.
Finally, one common mistake is to take the document structuring level as the
PostScript level. The current document structuring level is 3.x (Adobe updates
this stuff all the time -- it just keeps geting more complex). The current
language level, which you almost never see specified, is 2. The one you see
at the beginning of a PostScript file is the document structuring level, and
that tells you abolutely nothing about language usage in the file.
Ned