ares_get_servers_ports - Retrieve name servers from an initialized ares_channel
#include <ares.h> int ares_get_servers(ares_channel channel, struct ares_addr_node **servers) int ares_get_servers_ports(ares_channel channel, struct ares_addr_port_node **servers)
ARES_GET_SERVERS(3) Library Functions Manual ARES_GET_SERVERS(3)
NAME
ares_get_servers, ares_get_servers_ports - Retrieve name servers from
an initialized ares_channel
SYNOPSIS
#include <ares.h>
int ares_get_servers(ares_channel channel, struct ares_addr_node **servers)
int ares_get_servers_ports(ares_channel channel, struct ares_addr_port_node **servers)
DESCRIPTION
The ares_get_servers(3) function retrieves name servers configuration
from the channel data identified by channel, as a linked list of
ares_addr_node structs storing a pointer to the first node at the
address specified by servers.
The ares_get_servers_ports(3) function also retrieves any per-server
port information that may have been previously configured, returning a
linked list of ares_addr_port structures.
Function caller may traverse the returned name server linked list, or
may use it directly as suitable input for the ares_set_servers(3) /
ares_set_servers_ports(3) functions, but shall not shrink or extend the
list on its own.
Each node of the name server linked list is stored in memory dynami-
cally allocated and managed by c-ares. It is the caller's responsibil-
ity to free the resulting linked list, using ares_free_data(3) , once
the caller does not need it any longer.
This function is capable of handling IPv4 and IPv6 name server
addresses simultaneously, rendering ares_save_options(3) with optmask
ARES_OPT_SERVERS functionally obsolete except for IPv4-only name server
usage.
RETURN VALUES
This function may return any of the following values:
ARES_SUCCESS The name servers configuration was successfully
retrieved
ARES_ENOMEM The memory was exhausted
ARES_ENODATA The channel data identified by channel was invalid.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | library/libcares |
+---------------+------------------+
|Stability | Volatile |
+---------------+------------------+
SEE ALSO
ares_set_servers(3), ares_init_options(3), ares_save_options(3)
AVAILABILITY
ares_get_servers(3) was added in c-ares 1.7.1;
ares_get_servers_ports(3) was added in c-ares 1.11.0.
AUTHOR
Implementation of this function and associated library internals are
based on code, comments and feedback provided in November and December
of 2008 by Daniel Stenberg, Gregor Jasny, Phil Blundell and Yang Tse,
December 2009 by Cedric Bail, February 2010 by Jakub Hrozek. On March
2010 Yang Tse shuffled all the bits and this function popped out.
Copyright 1998 by the Massachusetts Institute of Technology.
Copyright (C) 2008-2010 by Daniel Stenberg
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/.
5 March 2010 ARES_GET_SERVERS(3)