> My point is that if the purpose of the attribute exchange is to avoid
> incompatibilities between sender and receiver, the current design isn't
> going to work reliably. For example, there is the scenario of a client
> sending a PS3 file to a PS2 IPP Printer.
You're making the very big assumption that PostScript breaks down cleanly by
simple version numbers. But it never has been this way, and hasn't been since
Level 2 was defined. Devices are free to implement subsets of level 2 or level
3 and can check the declarations in a document to see if the document uses
anything outside of the subset they implement. So a simple version number just
doesn't work very well for PostScript.
However, the earlier example I saw was PCL. I don't know enough about PCL to
say whether a simple version number is useful. If it is then defining a MIME
version parameter for PCL might be appropriate.
But while simple versioning through the use of MIME parameters is OK, anything
more than that isn't something MIME parameters were designed to do. Nor are
MIME content type parameters all that good at negotiating feature sets or
We have a mechanism for complex version and feature declaration and
negotiation: Media feature tags.
If attribute exchange is your goal you should be using media feature tags. MIME
content type parameter information is only a small subset of the information
available in this context. And if you need additional feature tags for
PostScript or PCL, by all means define them.
This archive was generated by hypermail 2b29 : Mon Mar 12 2001 - 13:08:27 EST