.\"
.\" Copyright 1998 by the Massachusetts Institute of Technology.
.\"
.\" Permission to use, copy, modify, and distribute this
.\" software and its documentation for any purpose and without
.\" fee is hereby granted, provided that the above copyright
.\" notice appear in all copies and that both that copyright
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.\" documentation, and that the name of M.I.T. not be used in
.\" advertising or publicity pertaining to distribution of the
.\" software without specific, written prior permission.
.\" M.I.T. makes no representations about the suitability of
.\" this software for any purpose.  It is provided "as is"
.\" without express or implied warranty.
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.\" SPDX-License-Identifier: MIT
.\"
.TH ARES_EXPAND_NAME 3 "20 Nov 2009"
.SH NAME
ares_expand_name \- Expand a DNS-encoded domain name
.SH SYNOPSIS
.nf
#include <ares.h>

int ares_expand_name(const unsigned char *\fIencoded\fP,
                     const unsigned char *\fIabuf\fP, int \fIalen\fP,
                     char **\fIs\fP, long *\fIenclen\fP)
.fi
.SH DESCRIPTION
The
.B ares_expand_name
function converts a DNS-encoded domain name to a dot-separated C
string.  The argument
.I encoded
gives the beginning of the encoded domain name, and the arguments
.I abuf
and
.I alen
give the containing message buffer (necessary for the processing of
indirection pointers within the encoded domain name).  The result is
placed in a NUL-terminated allocated buffer, a pointer to which is
stored in the variable pointed to by
.IR s .
The length of the encoded name is stored in the variable pointed to by
.I enclen
so that the caller can advance past the encoded domain name to read
further data in the message.

Use \fIares_free_string(3)\fP to free the allocated hostname.
.SH RETURN VALUES
.B ares_expand_name
can return any of the following values:
.TP 15
.B ARES_SUCCESS
Expansion of the encoded name succeeded.
.TP 15
.B ARES_EBADNAME
The encoded domain name was malformed and could not be expanded.
.TP 15
.B ARES_ENOMEM
Memory was exhausted.
.SH SEE ALSO
.BR ares_mkquery (3), ares_free_string (3)
.SH AUTHOR
Greg Hudson, MIT Information Systems
.br
Copyright 1998 by the Massachusetts Institute of Technology.