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GETADDRINFO(1)		FreeBSD	General	Commands Manual		GETADDRINFO(1)

     getaddrinfo -- resolve names to socket addresses

     getaddrinfo [-cNnP] [-f family] [-p protocol] [-s service[/protocol]]
		 [-t socktype] [hostname]

     The getaddrinfo utility resolves host and service names to	socket ad-
     dresses with getaddrinfo(3) and prints them to standard output in a user-
     friendly format.

     The output	is a sequence of lines with space-separated fields:

	   socket-type address-family protocol [af-specific data ...]

     For the "inet" and	"inet6"	address	families, the af-specific data are the
     IP/IPv6 address and port number.

     Depending on the settings in nsswitch.conf(5), getaddrinfo	might query
     DNS for answers.  However,	it is not intended to be a general-purpose DNS
     query utility.  Use drill(1) for that.

     These options are available:

     -c	     Look up a canonical name as if with the AI_CANONNAME flag to
	     getaddrinfo(3) and	print it on the	first line before the socket

     -f	family
	     Specify an	address	family.	 Address families are named like the
	     AF_... constants for address family numbers in the	<sys/socket.h>
	     header file but without the AF_ prefix and	lowercase.  For	exam-
	     ple, "inet" corresponds with AF_INET.

     -N	     Treat the service as numeric and do not attempt service name res-
	     olution, as if with the AI_NUMERICSERV flag to getaddrinfo(3).

     -n	     Treat the hostname	as a numeric address and do not	attempt	name
	     resolution, as if with the	AI_NUMERICHOST flag to getaddrinfo(3).

     -P	     Return socket addresses intended for use with bind(2), as if with
	     the AI_PASSIVE flag to getaddrinfo(3).  By	default, the socket
	     addresses are intended for	use with connect(2), sendto(2),	or

     -p	protocol
	     Specify a protocol.  Protocols are	numeric	or symbolic as listed
	     in	protocols(5).

     -s	service[/protocol]
	     Specify a service to look up.  Services are symbolic or numeric
	     with an optional protocol suffix as listed	in services(5).	 If a
	     service is	not specified, a hostname is required.

     -t	socktype
	     Specify a socket type.  Socket types are named like the SOCK_...
	     constants for socket type numbers in the <sys/socket.h> header
	     file but without the SOCK_	prefix and lowercase.  For example,
	     "dgram" corresponds with SOCK_DGRAM.

     The getaddrinfo utility exits 0 on	success, and >0	if an error occurs.

     Look up "":

	   $ getaddrinfo
	   dgram inet6 udp 2001:4f8:3:7:2e0:81ff:fe52:9ab6 0
	   dgram inet udp 0
	   stream inet6	tcp 2001:4f8:3:7:2e0:81ff:fe52:9ab6 0
	   stream inet tcp	0

     The port number here is zero because no service was specified.

     Look up "" for stream sockets on port 80,	and show the
     canonical name:

	   $ getaddrinfo -c -t stream -s 80
	   stream inet6	tcp 2001:470:1f05:3d::21 80
	   stream inet tcp 80

     drill(1), getent(1), getaddrinfo(3), getnameinfo(3), resolver(3),
     hosts(5), nsswitch.conf(5), protocols(5), resolv.conf(5), services(5)

     The getaddrinfo command first appeared in NetBSD 7.0.

FreeBSD	13.0			March 20, 2017			  FreeBSD 13.0


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