home | help 
GETADDRINFO(1)		     General Commands Manual		  GETADDRINFO(1)

NAME
     getaddrinfo -- resolve names to socket addresses

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

DESCRIPTION
     The getaddrinfo utility resolves host and service names to socket addresses
     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 getad-
	     drinfo(3) and print it on the first  line	before	the  socket  ad-
	     dresses.

     -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 example,
	     "inet" corresponds with AF_INET.

     -N      Treat  the service as numeric and do not attempt service name reso-
	     lution, 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  ad-
	     dresses  are  intended  for  use  with  connect(2),  sendto(2),  or
	     sendmsg(2).

     -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.

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

EXAMPLES
     Look up "www.NetBSD.org":

	   $ getaddrinfo www.NetBSD.org
	   dgram inet6 udp 2001:4f8:3:7:2e0:81ff:fe52:9ab6 0
	   dgram inet udp 149.20.53.67 0
	   stream inet6 tcp 2001:4f8:3:7:2e0:81ff:fe52:9ab6 0
	   stream inet tcp 149.20.53.67 0

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

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

	   $ getaddrinfo -c -t stream -s 80 morden.NetBSD.org
	   canonname ftp.NetBSD.org
	   stream inet6 tcp 2001:470:1f05:3d::21 80
	   stream inet tcp 199.233.217.249 80

SEE ALSO
     drill(1), getent(1), getaddrinfo(3), getnameinfo(3), resolver(3), hosts(5),
     nsswitch.conf(5), protocols(5), resolv.conf(5), services(5), ip6addrctl(8)

HISTORY
     The getaddrinfo command first appeared in NetBSD 7.0.

FreeBSD 15.1			 March 20, 2017 		  GETADDRINFO(1)
home | help