.\"

.\" Copyright 2010 by Ben Greear <greearb@candelatech.com>

.\"

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.\" fee is hereby granted, provided that the above copyright

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.\" M.I.T. makes no representations about the suitability of

.\" this software for any purpose.  It is provided "as is"

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.\"

.TH ARES_SET_SERVERS 3 "5 March 2010"

.SH NAME

ares_set_servers, ares_set_servers_ports \- Initialize an ares_channel name servers configuration

.SH SYNOPSIS

.nf

.B #include <ares.h>

.PP

.B int ares_set_servers(ares_channel \fIchannel\fP, struct ares_addr_node *\fIservers\fP)

.B int ares_set_servers_ports(ares_channel \fIchannel\fP, struct ares_addr_port_node *\fIservers\fP)

.fi

.SH DESCRIPTION

The \fBares_set_servers(3)\fP function initializes name servers configuration

for the channel data identified by

.IR channel ,

from a

.IR servers

pointer to a linked list of ares_addr_node structs holding name servers

address data.

.PP

The name server linked list pointer argument may be the result of a previous

call to \fBares_get_servers(3)\fP or a linked list of \fBares_addr_node\fP structs

set up by other means.

.PP

The \fBares_set_servers(3)\fP function also allows the specification of UDP and

TCP ports to be used for communication on a per-server basis.  The provided

linked list argument may be the result of a previous call to

\fBares_get_servers_ports(3)\fP or a linked list of \fBares_addr_port_node\fP structs

set up by other means.

.PP

This function replaces any potentially previously configured name servers

with the ones given in the linked list. So, in order to configure a channel

with more than one name server all the desired ones must be specified in a

single list.

.PP

The function does not take ownership of the linked list argument.

The caller is responsible for freeing the linked list when no longer needed.

.PP

This function is capable of handling IPv4 and IPv6 name server

addresses simultaneously, rendering \fBares_init_options(3)\fP with

optmask \fBARES_OPT_SERVERS\fP functionally obsolete except for

IPv4-only name server usage.

.SH RETURN VALUES

.B ares_set_servers(3)

may return any of the following values:

.TP 15

.B ARES_SUCCESS

The name servers configuration was successfully initialized.

.TP 15

.B ARES_ENOMEM

The process's available memory was exhausted.

.TP 15

.B ARES_ENODATA

The channel data identified by 

.IR channel

was invalid.

.TP 15

.B ARES_ENOTINITIALIZED

c-ares library initialization not yet performed.

.SH SEE ALSO

.BR ares_set_servers_csv (3),

.BR ares_get_servers (3),

.BR ares_init_options (3),

.BR ares_dup(3)

.SH AVAILABILITY

\fBares_set_servers(3)\fP was added in c-ares 1.7.1;

\fBares_set_servers_ports(3)\fP was added in c-ares 1.11.0.

.SH 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.

.br

Copyright 1998 by the Massachusetts Institute of Technology.

.br

Copyright (C) 2008-2010 by Daniel Stenberg