Section: C Library Functions (3)
Updated: 20 Nov 2009
ares_mkquery - Compose a single-question DNS query buffer
int ares_mkquery(const char *name, int dnsclass, int type,
Deprecated function. See ares_create_query(3)
function composes a DNS query with a single question.
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
give the class and type of the query using the values defined in
gives a 16-bit identifier for the query. The parameter
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
and the length of which will be stored in the variable pointed to by
It is the caller's responsibility to free this buffer using
ares_free_string(3) when it is no longer needed.
Usage of ares_mkquery(3) is deprecated, whereas the function is
equivalent to ares_create_query(3) with max_udp_size set to
can return any of the following values:
Construction of the DNS query succeeded.
The query name
refers to a
domain name. See RFC 7686.
The query 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
Memory was exhausted.
Greg Hudson, MIT Information Systems
Copyright 1998, 2000 by the Massachusetts Institute of Technology.