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getaddrinfo(3) on numerical addresses



I've noticed[*] that on NetBSD, getaddrinfo(3) does a resolver lookup even 
if presented a numerical address. Is this on purpose? Would it have a 
drawback if it would first try to inet_pton() the address?
On Linux, it seems to avoid the resolver lookup.

* The problem was net/nagios-plugins' check_ping to stall during a resolver 
malfunction (despite the addresses given numerically). It turned out that 
check_ping, in order to find out whether it needs to call a syntactically 
different ping6 command, checks whether the -H argument is IPv6. It does 
this eventually by calling getaddrinfo() with an AF_INET6 hint, resulting 
in resolver lookups, which failed.


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