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Re: getaddrinfo(3) on numerical addresses

On Oct 24,  7:32pm, Edgar =?iso-8859-1?B?RnXf?= 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.

     This totally sounds like a bug in the monitoring system, not
a libc bug.  If it is depending on esoteric implementation defined
behaviour then it is buggy and needs to find another way to do
what it wants.

} I guess the point is what you expect getaddrinfo on with a AF_INET6 
} hint to do. Well, you could have a search domain of and 
} have an AAAA record. How likely is that? 

     Irrelevant how likely it is.  If it is legal then getaddrinfo()
needs to handle it.

}-- End of excerpt from Edgar =?iso-8859-1?B?RnXf?=

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