ARES_CREATE_QUERY(3) Introduction to Library Functions ARES_CREATE_QUERY(3)
NAME
ares_create_query - Compose a single-question DNS query buffer
SYNOPSIS
#include <ares.h>
int ares_create_query(const char *
name,
int
dnsclass,
int
type,
unsigned short
id,
int
rd,
unsigned char **
buf,
int *
buflen,
int
max_udp_size)
DESCRIPTION
This function is deprecated as of c-ares 1.22, please use
ares_dns_record_create(3) instead.
The
ares_create_query(3) function composes a DNS query with a single
question. The parameter
name gives the query name as a NUL-
terminated C string of period-separated labels optionally ending with
a period; periods and backslashes within a label must be escaped with
a backlash.
The parameters
dnsclass and
type give the class and type of the query
using the values defined in
<arpa/nameser.h>.
The parameter
id gives a 16-bit identifier for the query.
The parameter
rd should be nonzero if recursion is desired, zero if
not.
The query will be placed in an allocated buffer, a pointer to which
will be stored in the variable pointed to by
buf, and the length of
which will be stored in the variable pointed to by
buflen.
It is the caller's responsibility to free this buffer using
ares_free_string(3) when it is no longer needed. The parameter
max_udp_size should be nonzero to activate EDNS. Usage of
ares_create_query(3) with
max_udp_size set to zero is equivalent to
using
ares_mkquery(3).
RETURN VALUES
ares_create_query can return any of the following values:
ARES_SUCCESS Construction of the DNS query succeeded.
ARES_ENOTFOUND The query name
name refers to a
.onion domain name.
See RFC 7686.
ARES_EBADNAME The query name
name could not be encoded as a domain
name, either because it contained a zero-length label
or because it contained a label of more than 63
characters.
ARES_ENOMEM Memory was exhausted.
AVAILABILITY
Added in c-ares 1.10.0
SEE ALSO
ares_dns_record(3),
ares_expand_name(3),
ares_free_string(3),
ares_mkquery(3) 17 Aug 2012 ARES_CREATE_QUERY(3)
