[Slightly OT] attribute value length limits

[Jakob Fix]

Hi Marcus,

thanks for your reply.

On 15/12/05, mcarr at allette.com.au <mcarr at allette.com.au> wrote:
> Jakob Fix wrote:
>
> > I am doing some testing for export of a Frame (7.1) document to XML and
> > SGML.  I am particularly interested in the maximum length of attribute
> > values.  I found that there's not really a limit when exporting to XML
> > (I tried 5kb of text).  However, when exporting to SGML, it only exports
> > the first 511 (!) bytes, not even 512.
>
> Yebbut... why? I've never seen an attribute value that size. If I had a
> value that big, I'd be looking for some further breakdown of it. Are you
> sure that big a chunk is necessary to assist in the description of the
> element?

OK, let me explain. The thing is we're thinking about ways to add
metadata to a number of elements.  This will probably be a separate FM
or XML document that's linked to our main documents via ID values, all
this implemented as an API client.  Development will take time.

But: our authors are asking to put in this metadata as soon as
possible, so we're trying to find some temporary method, such as an
attribute which would have the advantage over an element that it is
hidden, and doesn't affect the layout of the page.  However, it would
be nice not being obliged to tell them to count the characters they
type in the box ...

So why SGML if these restrictions doesn't exist in XML? Obviously, it
would be simpler just to switch to XML applications instead of SGML,
but I do have some problems porting our existing API client from 5.5.6
to 7.x (I mean it compiles and all, all the SGML_ prefixed function
calls are replaced by Structured_ ones etc, but I get a number of
weird error messages when saving as XML).  Also, the "backend" which
will process these files is currently SGML-only and would have to be
rewritten (but it's written in an Omnimark-comparable scripting
language, called Balise, and the French company which created it
doesn't exist any more ... Talk about vendor independence :-))

> > I do seem to remember that this value can be fixed/increased in the
> > SGML declaration, however I can't find any documentation on which
> > keyword corresponds to attribute value length.  I tried LITLEN,
> > ATTSPLEN, and some others, but even their current values are not set
> > to 511 (or 512).  Or is this limitation to be looked for elsewhere?
>
> Some things can be changed in the SGML Declaration but the change won't be
> reflected in FrameMaker. I would have thought that LITLEN would be the one
> to change.
>
>
> Marcus

--
cheers,
Jakob.