1.\" $FreeBSD$ 2.\" $NetBSD: getaddrinfo.1,v 1.5 2014/04/22 06:02:06 wiz Exp $ 3.\" 4.\" Copyright (c) 2013 The NetBSD Foundation, Inc. 5.\" All rights reserved. 6.\" 7.\" This documentation is derived from text contributed to The NetBSD 8.\" Foundation by Taylor R. Campbell. 9.\" 10.\" Redistribution and use in source and binary forms, with or without 11.\" modification, are permitted provided that the following conditions 12.\" are met: 13.\" 1. Redistributions of source code must retain the above copyright 14.\" notice, this list of conditions and the following disclaimer. 15.\" 2. Redistributions in binary form must reproduce the above copyright 16.\" notice, this list of conditions and the following disclaimer in the 17.\" documentation and/or other materials provided with the distribution. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29.\" POSSIBILITY OF SUCH DAMAGE. 30.\" 31.Dd January 2, 2021 32.Dt GETADDRINFO 1 33.Os 34.Sh NAME 35.Nm getaddrinfo 36.Nd resolve names to socket addresses 37.Sh SYNOPSIS 38.Nm 39.Op Fl cNnP 40.Op Fl f Ar family 41.Op Fl p Ar protocol 42.Op Fl s Ar service Ns Op Ns / Ns Ar protocol 43.Op Fl t Ar socktype 44.Op Ar hostname 45.Sh DESCRIPTION 46The 47.Nm 48utility resolves host and service names to socket addresses with 49.Xr getaddrinfo 3 50and prints them to standard output in a user-friendly format. 51.Pp 52The output is a sequence of lines with space-separated fields: 53.Pp 54.Dl socket-type address-family protocol [af-specific data ...] 55.Pp 56For the 57.Dq inet 58and 59.Dq inet6 60address families, the af-specific data are the IP/IPv6 address and port 61number. 62.Pp 63Depending on the settings in 64.Xr nsswitch.conf 5 , 65.Nm 66might query DNS for answers. 67However, it is not intended to be a general-purpose DNS query utility. 68Use 69.Xr drill 1 70for that. 71.Pp 72These options are available: 73.Bl -tag -width Ds 74.It Fl c 75Look up a canonical name as if with the 76.Dv AI_CANONNAME 77flag to 78.Xr getaddrinfo 3 79and print it on the first line before the socket addresses. 80.It Fl f Ar family 81Specify an address family. 82Address families are named like the 83.Dv AF_... 84constants for address family numbers in the 85.Aq Pa sys/socket.h 86header file but without the 87.Dv AF_ 88prefix and lowercase. 89For example, 90.Dq inet 91corresponds with 92.Dv AF_INET . 93.It Fl N 94Treat the service as numeric and do not attempt service name 95resolution, as if with the 96.Dv AI_NUMERICSERV 97flag to 98.Xr getaddrinfo 3 . 99.It Fl n 100Treat the hostname as a numeric address and do not attempt name 101resolution, as if with the 102.Dv AI_NUMERICHOST 103flag to 104.Xr getaddrinfo 3 . 105.It Fl P 106Return socket addresses intended for use with 107.Xr bind 2 , 108as if with the 109.Dv AI_PASSIVE 110flag to 111.Xr getaddrinfo 3 . 112By default, the socket addresses are intended for use with 113.Xr connect 2 , 114.Xr sendto 2 , 115or 116.Xr sendmsg 2 . 117.It Fl p Ar protocol 118Specify a protocol. 119Protocols are numeric or symbolic as listed in 120.Xr protocols 5 . 121.It Fl s Ar service Ns Op Ns / Ns Ar protocol 122Specify a service to look up. 123Services are symbolic or numeric with an optional 124protocol suffix as listed in 125.Xr services 5 . 126If a service is not specified, a hostname is required. 127.It Fl t Ar socktype 128Specify a socket type. 129Socket types are named like the 130.Dv SOCK_... 131constants for socket type numbers in the 132.Aq Pa sys/socket.h 133header file but without the 134.Dv SOCK_ 135prefix and lowercase. 136For example, 137.Dq dgram 138corresponds with 139.Dv SOCK_DGRAM . 140.El 141.Sh EXIT STATUS 142.Ex -std getaddrinfo 143.Sh EXAMPLES 144Look up 145.Dq www.dragonflybsd.org : 146.Bd -literal -offset indent 147$ getaddrinfo www.dragonflybsd.org 148dgram inet udp 199.233.90.68 0 149stream inet tcp 199.233.90.68 0 150dgram inet6 udp 2001:470:1:43b:1::68 0 151stream inet6 tcp 2001:470:1:43b:1::68 0 152.Ed 153.Pp 154The port number here is zero because no service was specified. 155.Pp 156Look up 157.Dq www.dragonflybsd.org 158for stream sockets on port 80, and show the canonical name: 159.Bd -literal -offset indent 160$ getaddrinfo -c -t stream -s 80 www.dragonflybsd.org 161canonname leaf.dragonflybsd.org 162stream inet tcp 199.233.90.68 80 163stream inet6 tcp 2001:470:1:43b:1::68 80 164.Ed 165.Pp 166The 167.Dq www.dragonflybsd.org 168is a CNAME of 169.Dq leaf.dragonflybsd.org . 170.Sh SEE ALSO 171.Xr drill 1 , 172.Xr getent 1 , 173.Xr getaddrinfo 3 , 174.Xr getnameinfo 3 , 175.Xr resolver 3 , 176.Xr hosts 5 , 177.Xr nsswitch.conf 5 , 178.Xr protocols 5 , 179.Xr resolv.conf 5 , 180.Xr services 5 181.Sh HISTORY 182The 183.Nm 184command first appeared in 185.Nx 7.0 , 186and was imported to 187.Dx 5.9 . 188