ares_gethostbyaddr - Initiate a host query by address
#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)
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
addresses 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.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | library/libcares |
+---------------+------------------+
|Stability | Volatile |
+---------------+------------------+
SEE ALSO
ares_process(3), ares_gethostbyname(3)
AUTHOR
Greg Hudson, MIT Information Systems
Copyright 1998 by the Massachusetts Institute of Technology.
NOTES
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from https://c-ares.haxx.se/download/c-
ares-1.17.2.tar.gz.
Further information about this software can be found on the open source
community website at https://c-ares.haxx.se/.
24 July 1998 ARES_GETHOSTBYADDR(3)