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Re: HTTP/3 options

From: Samuel Hurst via curl-library <>
Date: Wed, 4 Jan 2023 11:08:15 +0000

On 04/01/2023 10:04, Stefan Eissing via curl-library wrote:>> Am
04.01.2023 um 10:50 schrieb Daniel Stenberg <>:
>> On Wed, 4 Jan 2023, Stefan Eissing wrote:
>>> And then there are the cases where someone really wants to nail it down. That is what we are talking here, I guess. Ultimately, what is given on the command line is converted by curl into TCP and/or QUIC and the ALPN list for the connection (ignoring the http: cases). For people who really want to control this, specifying the ALPN list on the command line seems the best option. Someone might want to check if a server is willing to negotiate "h3-29", for example.
>> I actually don't think we've had users ask for this level of fiddling in the past.
>> If we would allow that, I imagine we need to provide a mapping as well. Like send APLN XXX and if agreed to, treat it as if it is YYYY. If not, curl itself would need to know that "h3-moonbase" is that new magic h3 attempt I work on in secret, possibly by making assumptions about how the id is created.
> I think we need to deal with those values found in HTTPS records. If we want to expose that on the command line is another thing. agreed.

I was just about to post on the subject of DNS service binding [1] for
discovering h3. Although given there's no current interface for
discovering SVCB records via getaddrinfo, is this more a discussion for
c-ares? What implications might that have to the curl interface if it's
been built with ares?


Received on 2023-01-04