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Re: getaddrinfo(3) on numerical addresses

In Edgar Fu? <> wrote:

>> I suspect there's some misunderstanding.
> Yes. It's about numerical IPv4 addresses being looked up with an
> AF_INET6 hint.
> check_ping tries to figure out whether it needs to call ping6 (suppose 
> wer'e on a system where ping6 is different from ping).
> Suppose that check_ping is invoked without -4/-6 and with -H
> Now check_ping tries to figure out whether the -H argument is a/resolves to 
> a IPv6 address. To do so, it checks whether getaddrinfo() on the -H argument 
> (which is with an AF_INET6 hint succeeds. But this triggers a DNS 
> lookup.
> Given this is a monitoring system, who's job it is to detect server failures, 
> marking random servers/switches as dead while the resolver is going mad and
> so check_ping on their numerical IPv4 times out is not particularily useful.

BTW, isn't that exactly the argument that this program must use
AI_NUMERICHOST which guarantees that no name resolution will be


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