1ARES_CREATE_QUERY(3)       Library Functions Manual       ARES_CREATE_QUERY(3)
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NAME

6       ares_create_query - Compose a single-question DNS query buffer
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SYNOPSIS

9       #include <ares.h>
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11       int ares_create_query(const char *name,
12                             int dnsclass,
13                             int type,
14                             unsigned short id,
15                             int rd,
16                             unsigned char **buf,
17                             int *buflen,
18                             int max_udp_size)
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DESCRIPTION

21       The  ares_create_query(3)  function  composes a DNS query with a single
22       question.  The parameter name gives the query name as a  NUL-terminated
23       C  string  of  period-separated labels optionally ending with a period;
24       periods and backslashes within a label must be escaped with a backlash.
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26       The parameters dnsclass and type give the class and type of  the  query
27       using the values defined in <arpa/nameser.h>.
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29       The parameter id gives a 16-bit identifier for the query.
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31       The  parameter  rd  should  be nonzero if recursion is desired, zero if
32       not.
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34       The query will be placed in an allocated buffer,  a  pointer  to  which
35       will  be  stored  in  the variable pointed to by buf, and the length of
36       which will be stored in the variable pointed to by buflen.
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38       It  is  the  caller's  responsibility  to  free   this   buffer   using
39       ares_free_string(3)  when  it  is  no  longer  needed.   The  parameter
40       max_udp_size should be nonzero to activate  EDNS.  Usage  of  ares_cre‐
41       ate_query(3) with  max_udp_size  set  to  zero  is  equivalent to using
42       ares_mkquery(3).
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RETURN VALUES

45       ares_create_query can return any of the following values:
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47       ARES_SUCCESS   Construction of the DNS query succeeded.
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49       ARES_EBADNAME  The query name name could not be  encoded  as  a  domain
50                      name, either because it contained a zero-length label or
51                      because it contained a label of more than 63 characters.
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53       ARES_ENOMEM    Memory was exhausted.
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AVAILABILITY

56       Added in c-ares 1.10.0
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SEE ALSO

59       ares_expand_name(3), ares_free_string(3), ares_mkquery(3)
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AUTHOR

62                                  17 Aug 2012             ARES_CREATE_QUERY(3)