I like the idea of adding additional bit to CURLOPT_IPRESOLVE, but actually I
think about the "Auto" or "Dual" mode, which should probably provide the
current "both" IPv4 and IPv6 instead of the "Also" mode enforcing certain name
resolution (i.e. IPv4),.
And probably the "auto" mode should not
The terminology and behaviors here are conflating two very different things:
- What address types are added to the cache
- What addresses are used for a connection.
The name IPRESOLVE_* implies that it controls resolution, but the
description says it controls "what kind of IP addresses to use
