ares_mkquery - Compose a single-question DNS query buffer


#include <ares.h>

int ares_mkquery(const char *name, int dnsclass, int type, unsigned short id, int rd, unsigned char **buf, int *buflen)


Deprecated function. See ares_create_query(3) instead!

The ares_mkquery 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.

Usage of ares_mkquery(3) is deprecated, whereas the function is equivalent to ares_create_query(3) with max_udp_size set to 0.


ares_mkquery can return any of the following values:

ARES_SUCCESS Construction of the DNS query succeeded.

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.


ares_expand_name (3) ares_free_string (3)


Greg Hudson, MIT Information Systems

Copyright 1998, 2000 by the Massachusetts Institute of Technology.

This HTML page was made with roffit.