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robin.berjon@expway.fr (Robin Berjon) writes:
>In fact, if HTTP 1.1 content codings took parametres, we'd have the
>answer already. Damn :)
I'm not entirely sure what you're looking for - and Len's reply makes me
even less certain - but Content-Type header fields definitely take
parameters:
http://ietf.org/rfc/rfc2045.txt , Section 5
-----------------------
The Content-Type header field specifies the nature of the data in the
body of an entity by giving media type and subtype identifiers, and
by providing auxiliary information that may be required for certain
media types. After the media type and subtype names, the remainder
of the header field is simply a set of parameters, specified in an
attribute=value notation. The ordering of parameters is not
significant.
In general, the top-level media type is used to declare the general
type of data, while the subtype specifies a specific format for that
type of data. Thus, a media type of "image/xyz" is enough to tell a
user agent that the data is an image, even if the user agent has no
knowledge of the specific image format "xyz". Such information can
be used, for example, to decide whether or not to show a user the raw
data from an unrecognized subtype -- such an action might be
reasonable for unrecognized subtypes of text, but not for
unrecognized subtypes of image or audio. For this reason, registered
subtypes of text, image, audio, and video should not contain embedded
information that is really of a different type. Such compound
formats should be represented using the "multipart" or "application"
types.
Parameters are modifiers of the media subtype, and as such do not
fundamentally affect the nature of the content. The set of
meaningful parameters depends on the media type and subtype. Most
parameters are associated with a single specific subtype. However, a
given top-level media type may define parameters which are applicable
to any subtype of that type. Parameters may be required by their
defining content type or subtype or they may be optional. MIME
implementations must ignore any parameters whose names they do not
recognize.
For example, the "charset" parameter is applicable to any subtype of
"text", while the "boundary" parameter is required for any subtype of
the "multipart" media type.
-----------------------------
Maybe you need something stronger, which the next paragraph pushes
elsewhere:
-----------------------------
There are NO globally-meaningful parameters that apply to all media
types. Truly global mechanisms are best addressed, in the MIME
model, by the definition of additional Content-* header fields.
------------------------------
--
Simon St.Laurent
Ring around the content, a pocket full of brackets
Errors, errors, all fall down!
http://simonstl.com -- http://monasticxml.org
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