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.Dd April 22, 2014 .Dt GETADDRINFO 1 .Os .Sh NAME .Nm getaddrinfo .Nd resolve names to socket addresses .Sh SYNOPSIS .Nm .Op Fl cNnP .Op Fl f Ar family .Op Fl p Ar protocol .Op Fl s Ar service Ns Op Ns / Ns Ar protocol .Op Fl t Ar socktype .Op Ar hostname .Sh DESCRIPTION The .Nm utility resolves host and service names to socket addresses as if with the .Xr getaddrinfo 3 routine and formats them to standard output.
p The output is a sequence of lines of space-separated fields:
p .Dl socket-type address-family protocol [af-specific data ...]
p For the .Dq inet and .Dq inet6 address families, the af-specific data are the IP/IPv6 address and port number.
p Although the .Nm utility may query the DNS to give answers, depending on the system's .Xr nsswitch.conf 5 configuration, it is not intended to be a general-purpose utility to query the DNS; use the .Xr dig 1 utility for that.
p The following options are available: l -tag -width Ds t Fl c Look up a canonical name as if with the .Dv AI_CANONNAME flag to .Xr getaddrinfo 3 and print it on the first line before the socket addresses. t Fl f Ar family Specify an address family. Address families are named like the .Dv AF_... constants for address family numbers in the .Aq Pa sys/socket.h header file but without the .Dv AF_ prefix and lowercase. For example, .Dq inet corresponds with .Dv AF_INET . t Fl N Treat the service as numeric and do not attempt service name resolution, as if with the .Dv AI_NUMERICSERV flag to .Xr getaddrinfo 3 . t Fl n Treat the hostname as a numeric address and do not attempt name resolution, as if with the .Dv AI_NUMERICHOST flag to .Xr getaddrinfo 3 . t Fl P Return socket addresses intended for use with .Xr bind 2 , as if with the .Dv AI_PASSIVE flag to .Xr getaddrinfo 3 . By default, the socket addresses are intended for use with .Xr connect 2 , .Xr sendto 2 , or .Xr sendmsg 2 . t Fl p Ar protocol Specify a protocol. Protocols may be numeric, or symbolic as listed in .Xr protocols 5 . t Fl s Ar service Ns Op Ns / Ns Ar protocol Specify a service to look up. Services may be symbolic or numeric with an optional protocol suffix as listed in .Xr services 5 . If no service is specified, a hostname must be specified. t Fl t Ar socktype Specify a socket type. Socket types are named like the .Dv SOCK_... constants for socket type numbers in the .Aq Pa sys/socket.h header file but without the .Dv SOCK_ prefix and lowercase. For example, .Dq dgram corresponds with .Dv SOCK_DGRAM . .El .Sh EXIT STATUS .Ex -std getaddrinfo .Sh EXAMPLES Look up .Dq www.NetBSD.org : d -literal -offset indent $ 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 .Ed
p The port number here is zero because no service was specified.
p Look up .Dq morden.NetBSD.org for stream sockets on port 80, and show the canonical name: d -literal -offset indent $ 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 .Ed .Sh SEE ALSO .Xr dig 1 , .Xr getent 1 , .Xr getaddrinfo 3 , .Xr getnameinfo 3 , .Xr resolver 3 , .Xr hosts 5 , .Xr nsswitch.conf 5 , .Xr protocols 5 , .Xr resolv.conf 5 , .Xr services 5 .Sh HISTORY The .Nm command first appeared in .Nx 7.0 .