[CFR] reflect resolv.conf update to running application

[Julian Elischer]

Hajimu UMEMOTO wrote:
> Hi,
> 
> Our resolver reads resolv.conf once, and never re-read it.  Recent
> OpenBSD changed to re-read resolv.conf when it is updated.  I believe
> it is useful specially for mobile environment.  So, I made a patch for
> our resolver.  Please review it.
> 


 From a very quick read I couldn't see when it does the update.
does it do it of EVERY lookup or only after a failed lookup?