ares_get_servers, ares_get_servers_ports - Retrieve name servers from an
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)
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
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)
functions, but shall not shrink or extend the
list on its own.
Each node of the name server linked list is stored in memory dynamically
allocated and managed by c-ares. It is the caller's responsibility 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)
functionally obsolete except for IPv4-only name server
This function may return any of the following values:
- The name servers configuration was successfully
- The memory was exhausted
- The channel data identified by channel was
was added in c-ares 1.7.1;
was added in c-ares 1.11.0.
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