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GETADDRINFO(1)         DragonFly 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_...
             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.dragonflybsd.org":

           $ getaddrinfo www.dragonflybsd.org
           dgram inet udp 199.233.90.68 0
           stream inet tcp 199.233.90.68 0
           dgram inet6 udp 2001:470:1:43b:1::68 0
           stream inet6 tcp 2001:470:1:43b:1::68 0

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

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

           $ getaddrinfo -c -t stream -s 80 www.dragonflybsd.org
           canonname leaf.dragonflybsd.org
           stream inet tcp 199.233.90.68 80
           stream inet6 tcp 2001:470:1:43b:1::68 80

     The "www.dragonflybsd.org" is a CNAME of "leaf.dragonflybsd.org".


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, and was imported to
     DragonFly 5.9.

DragonFly 5.9-DEVELOPMENT       January 2, 2021      DragonFly 5.9-DEVELOPMENT

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