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       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, char **buf,
            int *buflen)


       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 when it is no longer needed.


       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.

                                4 January 2000