CURLOPT_HTTP_VERSION no longer defaults to CURL_HTTP_VERSION_2TLS

[gmta]

Specify which documentation you found a problem with

• CURLOPT_HTTP_VERSION
• https://github.com/curl/curl/blob/master/docs/libcurl/opts/CURLOPT_HTTP_VERSION.md

The problem

In 279a477 the behavior of setting CURL_HTTP_VERSION_2TLS when CURL_HTTP_VERSION_NONE is provided was removed. The documentation still mentions the old default value of CURL_HTTP_VERSION_2TLS.

I'm unsure on how to update the documentation to properly reflect what, in hindsight, was a temporary change to the behavior of CURL_HTTP_VERSION_NONE - otherwise I'd have sent in a PR.

[icing]

If I understand you correctly, we should document that the default change to CURL_HTTP_VERSION_NONE?

I am not sure what you mean by "temporary change".

[gmta]

@icing

I am not sure what you mean by "temporary change".

Since curl 7.62.0 and before commit 279a477, the behavior of setting CURLOPT_HTTP_VERSION to CURL_HTTP_VERSION_NONE is to actually set CURL_HTTP_VERSION_2TLS instead, if HTTP/2 support was enabled. The current behavior is to actually set CURL_HTTP_VERSION_NONE again. That's what I meant by "temporary change" in behavior, since it was reverted.

If I understand you correctly, we should document that the default change to CURL_HTTP_VERSION_NONE?

Yes.

[bagder]

CURL_HTTP_VERSION_NONE is documented as

We do not care about what version the library uses. libcurl uses whatever it thinks fit

I think it sounds like this still applies...

[gmta]

CURL_HTTP_VERSION_NONE is documented as

We do not care about what version the library uses. libcurl uses whatever it thinks fit

I think it sounds like this still applies...

It does! It's just that CURL_HTTP_VERSION_NONE is the actual default value, and not CURL_HTTP_VERSION_2TLS.

There is a minor behavioral difference in that curl_easy_getinfo(handle, CURLINFO_HTTP_VERSION, &http_version); would show a different value after setting CURL_HTTP_VERSION_NONE before and after that commit.
Update: there doesn't seem to be a difference in the return value for this, since it will reflect the effective HTTP version, not the requested one.

If that's all OK, a simple documentation update would be enough.