Re: estimated Content-Length with chunked encoding

Adrien de Croy wrote:
> Therefore before sending any chunked request, the client would need to 
> establish a-priori that the request path was capable of successfully 
> processing a chunked request.
> 
> It's not necessarily trivial to do this reliably.

What about sending "Expect: 100-continue" in the request headers, and
waiting for a "100 Continue" response.  If you get one, you _ought_ to
be able to assume it's a chunked-request-capable HTTP/1.1 server or
proxy, and if you don't, you time out, abort that connection (because
you don't know if it will interpret Transfer-Encoding), and try again
with a non-chunked request.

Does that work in principle, disregarding broken implementations?

Does it work in practice?

-- Jamie