In <9302181227(_dot_)AA00324(_at_)tardis(_dot_)shearson(_dot_)com>
rens(_at_)lorax(_dot_)shearson(_dot_)com (Rens Troost) writes:
But on the question of encoding, type, and Macs; I think that the
problem is more sticky than it seems at first. If macintosh MUAs just
wrap up binary files as binhex/QP or B64ed 'application/mac-file', you
lose interoperability with other platforms. At the very least you
should distinguish between files that have and empty resource fork
(plain data files) and others.
Even this may not be a sure guide, though, as I have seen apps that
keep all the important info in their data files data fork, but also
put some hints or even just timestamp/ID in the resource fork. The nub
of the problem; if I have a GIF on a mac, and I want to send it to my
friend who uses a 8088 box running OS/9, I want it to arrive as
image/gif, not application/mac-file.
Another possibility is to make a subtype of multipart - for example,
multipart/macintosh-file. This would imply two sub-parts, and parameters to
the parent type could identify the resource and data forks. e.g.:
I volunteer to work on a solution to this quandary. Would anyone like
to help out? We had best involve some authors of Macintosh mailers...
-Rens
If you're going to go this step, perhaps it's time to make the typing
sufficiently flexible that it will accomodate other systems with unique
file types... There are attributes to some file types that are unique to
different platforms, from items as simple as record size, variable/fixed/
undefined record sizes, creation date, last modification date, creator's
id/logon, to other more unique fields like "user label areas" as used on
HP3000 computer systems. All can be critical to the ability to usefully
transport a data (or executable) file among systems. I'm sure proponents
of other systems can come up with even longer lists of such items. Suppose
one wanted to send an SQL data set via e-mail? (gag - I know) But it is
conveivable that any arbitrary platform might be able to provide such
data to another, and perhaps even a suitable standard could cope with
all the applicable attributes...
I don't know if it's even possible to come up with a comprehensive list
of unique atributes among different platforms, and it would certainly miss
several options.
As it turns out, we've been using a defacto standard for encoding HP3000
files within MIME attachments and our hopes of ever getting a "portable"
standardized solution that would work with HP3000 systems are dim...
-Chris
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Chris Bartram Internet: RCB(_at_)UII(_dot_)COM
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