ares_create_query - question DNS query buffer
#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)
ARES_CREATE_QUERY(3) Library Functions Manual 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
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_cre-
ate_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
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | library/libcares |
+---------------+------------------+
|Stability | Volatile |
+---------------+------------------+
SEE ALSO
ares_expand_name(3), ares_free_string(3), ares_mkquery(3)
AUTHOR
NOTES
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from https://c-ares.haxx.se/download/c-
ares-1.17.2.tar.gz.
Further information about this software can be found on the open source
community website at https://c-ares.haxx.se/.
17 Aug 2012 ARES_CREATE_QUERY(3)