1ARES_MKQUERY(3) Library Functions Manual ARES_MKQUERY(3)
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6 ares_mkquery - Compose a single-question DNS query buffer
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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, char **buf,
13 int *buflen)
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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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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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41 ares_expand_name(3), ares_free_string(3)
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44 Greg Hudson, MIT Information Systems
45 Copyright 1998, 2000 by the Massachusetts Institute of Technology.
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49 4 January 2000 ARES_MKQUERY(3)