lwres_getnameinfo(3)

LWRES_GETNAMEINFO(3)          BIND9          LWRES_GETNAMEINFO(3)

NAME

     lwres_getnameinfo - lightweight resolver socket address
     structure to hostname and service name

SYNOPSIS

     #include <lwres/netdb.h>

     int lwres_getnameinfo(const struct sockaddr *sa,
                           size_t salen, char *host

DESCRIPTION

     This function is equivalent to the getnameinfo(3) function
     defined in RFC2133.  lwres_getnameinfo() returns the
     hostname for the struct sockaddrsa which is salen bytes
     long. The hostname is of length hostlen and is returned via
     *host.  The maximum length of the hostname is 1025 bytes:
     NI_MAXHOST.

     The name of the service associated with the port number in
     sa is returned in *serv.  It is servlen bytes long. The
     maximum length of the service name is NI_MAXSERV - 32 bytes.

     The flags argument sets the following bits:

     NI_NOFQDN
         A fully qualified domain name is not required for local
         hosts. The local part of the fully qualified domain name
         is returned instead.

     NI_NUMERICHOST
         Return the address in numeric form, as if calling
         inet_ntop(), instead of a host name.

     NI_NAMEREQD
         A name is required. If the hostname cannot be found in
         the DNS and this flag is set, a non-zero error code is
         returned. If the hostname is not found and the flag is
         not set, the address is returned in numeric form.

     NI_NUMERICSERV
         The service name is returned as a digit string
         representing the port number.

     NI_DGRAM
         Specifies that the service being looked up is a datagram
         service, and causes getservbyport() to be called with a
         second argument of "udp" instead of its default of
         "tcp". This is required for the few ports (512-514) that
         have different services for UDP and TCP.

RETURN VALUES

ISC                  Last change: 2007-06-18                    1

LWRES_GETNAMEINFO(3)          BIND9          LWRES_GETNAMEINFO(3)

     lwres_getnameinfo() returns 0 on success or a non-zero error
     code if an error occurs.

SEE ALSO

     RFC2133(), getservbyport(3), lwres(3), lwres_getnameinfo(3),
     lwres_getnamebyaddr(3).  lwres_net_ntop(3).

BUGS

     RFC2133 fails to define what the nonzero return values of
     getnameinfo(3) are.

AUTHOR

     Internet Systems Consortium, Inc.

COPYRIGHT

     Copyright 8c9 2004, 2005, 2007, 2014-2016 Internet Systems
     Consortium, Inc. ("ISC")
     Copyright 8c9 2000, 2001 Internet Software Consortium.

ISC                  Last change: 2007-06-18                    2