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ARES_GETHOSTBYADDR(3)	   Library Functions Manual	 ARES_GETHOSTBYADDR(3)

NAME
       ares_gethostbyaddr - Initiate a host query by address

SYNOPSIS
       #include	<ares.h>

       typedef void (*ares_host_callback)(void *arg, int status,
       int timeouts, struct hostent *hostent)

       void ares_gethostbyaddr(ares_channel channel, const void	*addr,
	    int	addrlen, int family, ares_host_callback	callback,
	    void *arg)

DESCRIPTION
       The  ares_gethostbyaddr	function  initiates a host query by address on
       the name	service	channel	identified by channel.	 The  parameters  addr
       and addrlen give	the address as a series	of bytes, and family gives the
       type of address.	 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_gethostbyaddr argu-
       ment arg.  The callback argument	status	indicates  whether  the	 query
       succeeded 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  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.

       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 hostent
       points to a struct hostent containing the name of the host returned  by
       the  query.   The  callback need	not and	should not attempt to free the
       memory pointed to by hostent; the ares library will free	 it  when  the
       callback	 returns.  If the query	did not	complete successfully, hostent
       will be NULL.

SEE ALSO
       ares_process(3),	ares_gethostbyname(3)

AUTHOR
       Greg Hudson, MIT	Information Systems
       Copyright 1998 by the Massachusetts Institute of	Technology.

				 24 July 1998		 ARES_GETHOSTBYADDR(3)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | AUTHOR

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