2 .\" Copyright 1998, 2000 by the Massachusetts Institute of Technology.
4 .\" Permission to use, copy, modify, and distribute this
5 .\" software and its documentation for any purpose and without
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11 .\" software without specific, written prior permission.
12 .\" M.I.T. makes no representations about the suitability of
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14 .\" without express or implied warranty.
16 .TH ARES_MKQUERY 3 "20 Nov 2009"
18 ares_mkquery \- Compose a single-question DNS query buffer
23 .B int ares_mkquery(const char *\fIname\fP, int \fIdnsclass\fP, int \fItype\fP,
24 .B unsigned short \fIid\fP, int \fIrd\fP, unsigned char **\fIbuf\fP,
30 function composes a DNS query with a single question.
33 gives the query name as a NUL-terminated C string of period-separated
34 labels optionally ending with a period; periods and backslashes within
35 a label must be escaped with a backlash. The parameters
39 give the class and type of the query using the values defined in
40 .BR <arpa/nameser.h> .
43 gives a 16-bit identifier for the query. The parameter
45 should be nonzero if recursion is desired, zero if not. The query
46 will be placed in an allocated buffer, a pointer to which will be
47 stored in the variable pointed to by
49 and the length of which will be stored in the variable pointed to by
51 It is the caller's responsibility to free this buffer using
52 \fIares_free_string(3)\fP when it is no longer needed.
55 can return any of the following values:
58 Construction of the DNS query succeeded.
63 could not be encoded as a domain name, either because it contained a
64 zero-length label or because it contained a label of more than 63
70 .BR ares_expand_name (3),
71 .BR ares_free_string (3)
73 Greg Hudson, MIT Information Systems
75 Copyright 1998, 2000 by the Massachusetts Institute of Technology.