[PATCH] CYGWIN: Fix resolver debugging output

Brian Inglis Brian.Inglis@SystematicSw.ab.ca
Tue Feb 2 18:02:41 GMT 2021

On 2021-02-01 12:02, Corinna Vinschen via Cygwin-patches wrote:
> On Feb  1 15:46, Lavrentiev, Anton (NIH/NLM/NCBI) [C] via Cygwin-patches wrote:
>>> Except, the value has no meaning for ipv6.
>> It'll print all 0's :-)  But: minires does not make use of the _ext field.
>> It does use the conventional nsaddr_list (which is IPv4), but only if
>> Windows native DNS API is not used: "osquery"(aka use_os)=0. >>
>> For debugging purposes, that is enough and very convenient (yet the output 
>> needed some tune-up, which I suggested in my patch).

> Ok.

>> But for practical purposes, only Windows API should be used in regular 
>> applications (which is the default, anyways, since /etc/resolv.conf is not
>> routinely provided, so "osquery=1" implicitly).
> Yeah, I think so, too.  Ideally we should have stripped out all code
> providing non-Windows means (i. e., /etc/resolv.conf support) back when
> this code was folded into Cygwin.  It just doesn't make sense, at least
> not by default.

I've been generating /etc/resolv.conf -> /run/resolvconf/resolv.conf for years 
in an /etc/postinstall/0p_...dash script from ipconfig /all output (not aware of 
a Cygwin source to get this interface info) also run at startup, with some 
customizations, and not noticed any issues so far. Should I be wary in future?

>> I'm not sure if improvements to use _ext by the minires own code would be 
>> any beneficial.
>> Having said that, AAAA replies should be made understood by the 
>> minires-if-os shim code (and I can provide a patch for that, too).

> That would be great!

Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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