Re: Byte ranges -- formal spec proposal

James Gosling (jag@scndprsn.eng.sun.com)
Thu, 18 May 1995 03:15:50 +0500

> According to Daniel W. Connolly:
> >
> > A nice, clear, complete proposal. As you say, this could be done as a
> > server-private mechanism, but there's no reason why everybody
> > shouldn't do it the same way.
> >
> > A couple nits:
> >
> > > * The first byte in file is byte number 1.
> >
> > Blech. I'd rather it were 0. No biggie.
> >
>
> Base 0 is fine for bytes but would be problematic for other ranges.
> E.g.
>
> http://host/book;chapterrange=3-5
>
> would mean chapters 4 to 6 if base 0 is used. This would be just too
> confusing. We thought it better to be consistent and use the same
> base for everything.

I don't think this is relevant: http should be kept simple and data-type
independent, leave out the higher level semantics. Then 0 based
addressing is the most sensible. Even for chapters, the argument is
weak: what chapter number is the title page? What chapter number
applies to appendicies? Does the number then need to be a string that
names a sub-entity? This is a Pandora's Box that should stay closed.

Any thought on how this should interect with dynamic computed documents
(CGI-bin scripts)? Supporting range addressing of computed documents
would require either re-computation on each fetch, or caching. If
re-computed, how do you guarantee consistancy? Imagine fetching a
document one byte at a time that contains the server's load average.