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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,
			size_t hostlen, char *serv, size_t servlen,
			int flags);

DESCRIPTION
  This function is equivalent to the getnameinfo(3) function defined in
  RFC2133.  lwres_getnameinfo() returns the hostname for the struct sockaddr
  sa 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
  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.

COPYRIGHT
  Copyright (C) 2004, 2005 Internet Systems Consortium, Inc. ("ISC")

Index for Section 3

Alphabetical listing for L

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