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

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

9       #include <ares.h>
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11       int ares_mkquery(const char *name, int dnsclass, int type,
12       unsigned short id, int rd, unsigned char **buf,
13       int *buflen)
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DESCRIPTION

16       The  ares_mkquery function composes a DNS query with a single question.
17       The parameter name gives the query name as a NUL-terminated C string of
18       period-separated  labels  optionally  ending with a period; periods and
19       backslashes within a label must be escaped with a backlash.  The param‐
20       eters  dnsclass and type give the class and type of the query using the
21       values defined in <arpa/nameser.h>.  The parameter id  gives  a  16-bit
22       identifier for the query.  The parameter rd should be nonzero if recur‐
23       sion is desired, zero if not.  The query will be placed in an allocated
24       buffer, a pointer to which will be stored in the variable pointed to by
25       buf, and the length of which will be stored in the variable pointed  to
26       by buflen.  It is the caller's responsibility to free this buffer using
27       ares_free_string(3) when it is no longer needed.
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RETURN VALUES

30       ares_mkquery can return any of the following values:
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32       ARES_SUCCESS   Construction of the DNS query succeeded.
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34       ARES_EBADNAME  The query name name could not be  encoded  as  a  domain
35                      name, either because it contained a zero-length label or
36                      because it contained a label of more than 63 characters.
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38       ARES_ENOMEM    Memory was exhausted.
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SEE ALSO

41       ares_expand_name(3), ares_free_string(3)
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AUTHOR

44       Greg Hudson, MIT Information Systems
45       Copyright 1998, 2000 by the Massachusetts Institute of Technology.
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49                                  20 Nov 2009                  ARES_MKQUERY(3)