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ARES_GETNAMEINFO(3)	   Library Functions Manual	   ARES_GETNAMEINFO(3)

       ares_getnameinfo	- Address-to-nodename translation in protocol-indepen-
       dent manner

       #include	<ares.h>

       typedef void (*ares_nameinfo_callback)(void *arg, int status,
       int timeouts, char *node, char *service)

       void ares_getnameinfo(ares_channel channel, const struct	sockaddr *sa,
	    ares_socklen_t salen, int flags, ares_nameinfo_callback callback,
	    void *arg)

       The ares_getnameinfo function is	defined	for  protocol-independent  ad-
       dress  translation.  The	 function  is  a  combination of ares_gethost-
       byaddr(3) and getservbyport(3). The function will translate the address
       either by executing a host query	on the name service channel identified
       by channel or it	will attempt to	resolve	it locally if  possible.   The
       parameters  sa  and  len	 give the address as a sockaddr	structure, and
       flags gives the options that the	function will use.   Valid  flags  are
       listed below:

       ARES_NI_NOFQDN	  Only	the  nodename  portion of the FQDN is returned
			  for local hosts.

			  The numeric form of the hostname is returned	rather
			  than the name.

       ARES_NI_NAMEREQD	  An error is returned if the hostname cannot be found
			  in the DNS.

			  The numeric form of the service is  returned	rather
			  than the name.

       ARES_NI_TCP	  The service name is to be looked up for the TCP pro-

       ARES_NI_UDP	  The service name is to be looked up for the UDP pro-

       ARES_NI_SCTP	  The  service	name  is  to be	looked up for the SCTP

       ARES_NI_DCCP	  The service name is to be looked  up	for  the  DCCP

			  The  numeric form of the scope ID is returned	rather
			  than the name.

       ARES_NI_LOOKUPHOST A hostname lookup is being requested.

			  A service name lookup	is being requested.

       When the	query is complete or has failed, the ares library will	invoke
       callback.   Completion  or failure of the query may happen immediately,
       or may happen during a later call to  ares_process(3),  ares_destroy(3)
       or ares_cancel(3).

       The  callback argument arg is copied from the ares_getnameinfo argument
       arg.  The callback argument status indicates  whether  the  query  suc-
       ceeded  and,  if	 not, how it failed.  It may have any of the following

       ARES_SUCCESS	  The host lookup completed successfully.

       ARES_ENOTIMP	  The ares library does	not know how to	 look  up  ad-
			  dresses of type family.

       ARES_ENOTFOUND	  The address addr was not found.

       ARES_ENOMEM	  Memory was exhausted.

       ARES_ECANCELLED	  The query was	cancelled.

       ARES_EDESTRUCTION  The name service channel channel is being destroyed;
			  the query will not be	completed.

       ARES_EBADFLAGS	  The flags parameter contains an illegal value.

       The callback argument timeouts reports how many times a query timed out
       during the execution of the given request.

       On  successful completion of the	query, the callback argument node con-
       tains a string representing the hostname	 (assuming  ARES_NI_LOOKUPHOST
       was  specified).	 Additionally,	service	contains a string representing
       the service name	(assuming ARES_NI_LOOKUPSERVICE	 was  specified).   If
       the  query  did not complete successfully, or one of the	values was not
       requested, node or service will be NULL.


       Dominick	Meglio
       Copyright 2005 by Dominick Meglio.

				  1 May	2009		   ARES_GETNAMEINFO(3)


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