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.\"
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.\" Copyright 1998 by the Massachusetts Institute of Technology.
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.\" Copyright (C) 2008-2010 by Daniel Stenberg
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.\"
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.\" Permission to use, copy, modify, and distribute this
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.\" software and its documentation for any purpose and without
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.\" fee is hereby granted, provided that the above copyright
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.\" notice appear in all copies and that both that copyright
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.\" notice and this permission notice appear in supporting
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.\" documentation, and that the name of M.I.T. not be used in
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.\" advertising or publicity pertaining to distribution of the
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.\" software without specific, written prior permission.
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.\" M.I.T. makes no representations about the suitability of
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.\" this software for any purpose. It is provided "as is"
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.\" without express or implied warranty.
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.\"
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.TH ARES_GET_SERVERS 3 "5 March 2010"
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.SH NAME
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ares_get_servers \- Retrieve name servers from an initialized ares_channel
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.SH SYNOPSIS
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.nf
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.B #include <ares.h>
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.PP
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.B int ares_get_servers(ares_channel \fIchannel\fP, struct ares_addr_node **\fIservers\fP)
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.fi
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.SH DESCRIPTION
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The \fBares_get_servers(3)\fP function retrieves name servers configuration
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from the
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channel data identified by
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.IR channel ,
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as a linked list of ares_addr_node structs storing a pointer to the first
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node at the address specified by
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.IR servers .
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Function caller may traverse the returned name server linked list, or may use
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it directly as suitable input for the \fBares_set_servers(3)\fP function, but
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shall not shrink or extend the list on its own.
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Each node of the name server linked list is stored in memory dynamically
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allocated and managed by c-ares. It is the caller's responsibility to free
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the resulting linked list, using \fBares_free_data(3)\fP , once the caller
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does not need it any longer.
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This function is capable of handling IPv4 and IPv6 name server
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addresses simultaneously, rendering \fBares_save_options(3)\fP with
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optmask \fBARES_OPT_SERVERS\fP functionally obsolete except for
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IPv4-only name server usage.
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.SH RETURN VALUES
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.B ares_get_servers(3)
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may return any of the following values:
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.TP 15
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.B ARES_SUCCESS
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The name servers configuration was successfuly retrieved
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.TP 15
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.B ARES_ENOMEM
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The memory was exhausted
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.TP 15
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.B ARES_ENODATA
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The channel data identified by
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.IR channel
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was invalid.
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.SH SEE ALSO
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.BR ares_set_servers (3),
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.BR ares_init_options (3),
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.BR ares_save_options(3)
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.SH AVAILABILITY
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ares_get_servers(3) was added in c-ares 1.7.1
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.SH AUTHOR
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Implementation of this function and associated library internals are based
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on code, comments and feedback provided in November and December of 2008 by
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Daniel Stenberg, Gregor Jasny, Phil Blundell and Yang Tse, December 2009
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by Cedric Bail, February 2010 by Jakub Hrozek. On March 2010 Yang Tse
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shuffled all the bits and this function popped out.
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.br
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Copyright 1998 by the Massachusetts Institute of Technology.
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.br
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Copyright (C) 2008-2010 by Daniel Stenberg
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