🚀 go-pugleaf

I hate to say anything nice about using PostScript as a multi-media mail
standard, but I think the main problem with PostScript portability, in
this context, is that the language can make reference to external
resources (such as library files) which don't necessarily follow the
program to another site.  This is a problem that almost any language
could have, and could be solved in two ways for multimedia mail:

1.  Disable all such features.  In particular, this means the language
can't have a library.

2.  Modify the transport layer so that it recognizes the resources
required by each message, and packages them up to send to the next site
if necessary.  Thus if mail requires the "foobar" library, the first MTA
will ask the second MTA if it has the foobar library (appropriate
version number, presumably) and, if not, will transmit it to the
receiving site.

The second approach is somewhat flawed because it's hard to be sure  two
versions of a library are identical.  However, it closely resembles what
mail transport will have to look like when costly media such as video
are sent through the mail anyway, in my belief.  (You don't want to put
the video in the body, because many steps of the transport may be within
a domain where the video is uniformly accessable using some kind of
token.)

At any rate, I doubt that PostScript is any less portable than any other
representation that permits external references.  It seems to be a
pretty well-defined language.  -- Nathaniel