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 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 ares_mkquery(3).

RETURN VALUES

       ares_create_query 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.

AVAILABILITY

       Added in c-ares 1.10.0

SEE ALSO

       ares_expand_name(3), ares_free_string(3)

AUTHOR

                                           17 Aug 2012                       ARES_CREATE_QUERY(3)