getaddrinfo(1) - NetBSD Manual Pages

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GETADDRINFO(1)          NetBSD 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 as if with the getaddrinfo(3) routine and formats them to stan- dard output. The output is a sequence of lines of 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. Although the getaddrinfo utility may query the DNS to give answers, depending on the system's nsswitch.conf(5) configuration, it is not intended to be a general-purpose utility to query the DNS; use the dig(1) utility for that. The following 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 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 sendmsg(2). -p protocol Specify a protocol. Protocols may be numeric, or symbolic as listed in protocols(5). -s service[/protocol] Specify a service to look up. Services may be symbolic or numeric with an optional protocol suffix as listed in services(5). If no service is specified, a hostname must be specified. -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
dig(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. NetBSD 9.99 April 22, 2014 NetBSD 9.99
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