[Zlib-devel] Re: Inflate 1.2.beta0 available for testing

[Paul Marquess]

From: Mark Adler

> On Tuesday, November 26, 2002, at 10:40  AM, Paul Marquess wrote:
> > In practice I've found that a lot of browsers don't implement that
> > correctly - they will only accept RFC1951 content without the enclosing
> > RFC1950 envelope - that was true of both IE & Netscape. The only
> > browser I
> > could find that implemented it correctly was Opera, and it could handle
> > it
> > either way.
> >
> > Where you aware of this?
>
> Partly.  I knew that most browsers accepted gzip but not zlib content
> encoding.  However I thought that such a browser would include only
> "gzip" in its "Accept-Encoding" header.  What I think you're saying is
> that some browsers include "deflate" in the header, but are actually
> expecting a raw deflate stream instead of a zlib stream!

Precisely.

Just checked with the latest version of IE and it advertises

   Accept-Encoding: gzip, deflate

and the only "deflate" it can cope with is raw deflate.

> (This may be
> related to the poor naming of the "deflate" content encoding.  They
> probably should have called it "zlib".)

I think you are spot on there. When we were doing the proxy work, we found
we had to ban the use of the terms zlib and deflate and only use RFC1950 and
RFC1951. There was just too much confusion with the terms zlib and deflate.

By the way, apart from attempting to inflate it, is there any way to
determine if some content is raw deflate? This was the approach we took if
the content didn't have a valid zlib or gzip signature.

Paul

__________________________________________________
Do You Yahoo!?
Everything you'll ever need on one web page
from News and Sport to Email and Music Charts
http://uk.my.yahoo.com