Hi Scott, Bob, et al, Sunday (28 September 1997)
In light of the laudable concensus at the last PWG monthly meeting on
using RFC 2184 compliant charset/language tags in values of datatypes
'text' and 'name', I have a suggestion about the 'document-format'
operation attribute.
There is an obvious conflict between IPP's need for a 'document-format'
attribute (SHOULD contain both 'charset' and 'language') and the MIME
(and RFC 822) 'Content-Type' header (MAY contain 'charset', but MUST NOT
contain 'language' - see RFC 2046, pg 6, and recent IPP email from Larry
Masinter).
I suggest the following (no doubt fractured) ABNF for IPP's attribute
(using US-ASCII to specify all section keywords and section values):
document-format-value := " type "/" subtype "
";" "charset-section"
";" "language-section"
; for 'type' and 'subtype', see BNF for 'Content-Type', RFC 2045, pg 12
charset-section := "charset" "="
<registered character set name [IANA registry]>
language-section := "language" "="
<registered langauge tag [RFC 1766]>
Then, there is a simple mapping to the [MIME] headers of 'Content-Type'
(including charset) and 'Content-Language', while preserving the single,
unified attribute functionality for IPP.
Cheers,
- Ira McDonald (outside consultant at Xerox)
High North Inc
906-494-2434
PS - Note that the URL for IANA assignments (all registries) is:
"ftp://ftp.isi.edu/in-notes/iana/assignments/"