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ARES_CREATE_QUERY(3)  DragonFly 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 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)

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