debian man page for ares_getnameinfo

ARES_GETNAMEINFO(3)					     Library Functions Manual					       ARES_GETNAMEINFO(3)

NAME
       ares_getnameinfo - Address-to-nodename translation in protocol-independent manner

SYNOPSIS
       #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)

DESCRIPTION
       The  ares_getnameinfo  function	is  defined  for  protocol-independent address 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  iden-
       tified  by  channel  or it will attempt to resolve it locally if possible.  The parameters sa and len give the address as a sockaddr struc-
       ture, 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.

       ARES_NI_NUMERICHOST
			  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.

       ARES_NI_NUMERICSERV
			  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 protocol.

       ARES_NI_UDP	  The service name is to be looked up for the UDP protocol.

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

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

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

       ARES_NI_LOOKUPHOST A hostname lookup is being requested.

       ARES_NI_LOOKUPSERVICE
			  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  immedi-
       ately, 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 values:

       ARES_SUCCESS	  The host lookup completed successfully.

       ARES_ENOTIMP	  The ares library does not know how to look up addresses of type family.

       ARES_ENOTFOUND	  The address addr was not found.

       ARES_ENOMEM	  Memory was exhausted.

       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 contains 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.

SEE ALSO
       ares_process(3), ares_getaddrinfo(3)

AUTHOR
       Dominick Meglio
       Copyright 2005 by Dominick Meglio.

								    1 May 2009						       ARES_GETNAMEINFO(3)