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GETADDRINFO(1) FreeBSD 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 getaddrinfo(3) and print it on the first line before the socket addresses.
-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 resolution, 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 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_...
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)
HISTORY The getaddrinfo command first appeared in NetBSD 7.0.
FreeBSD 14.0-RELEASE-p11 March 20, 2017 FreeBSD 14.0-RELEASE-p11