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Diffstat (limited to 'src/c-ares/ares_create_query.3')
-rw-r--r-- | src/c-ares/ares_create_query.3 | 76 |
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diff --git a/src/c-ares/ares_create_query.3 b/src/c-ares/ares_create_query.3 new file mode 100644 index 000000000..59af0f0eb --- /dev/null +++ b/src/c-ares/ares_create_query.3 @@ -0,0 +1,76 @@ +.\" +.\" Copyright 1998 by the Massachusetts Institute of Technology. +.\" +.\" Permission to use, copy, modify, and distribute this +.\" software and its documentation for any purpose and without +.\" fee is hereby granted, provided that the above copyright +.\" notice appear in all copies and that both that copyright +.\" notice and this permission notice appear in supporting +.\" documentation, and that the name of M.I.T. not be used in +.\" advertising or publicity pertaining to distribution of the +.\" software without specific, written prior permission. +.\" M.I.T. makes no representations about the suitability of +.\" this software for any purpose. It is provided "as is" +.\" without express or implied warranty. +.\" +.TH ARES_CREATE_QUERY 3 "17 Aug 2012" +.SH NAME +ares_create_query \- Compose a single-question DNS query buffer +.SH SYNOPSIS +.nf +#include <ares.h> + +int ares_create_query(const char *\fIname\fP, + int \fIdnsclass\fP, + int \fItype\fP, + unsigned short \fIid\fP, + int \fIrd\fP, + unsigned char **\fIbuf\fP, + int *\fIbuflen\fP, + int \fImax_udp_size\fP) +.fi +.SH DESCRIPTION +The \fIares_create_query(3)\fP function composes a DNS query with a single +question. The parameter \fIname\fP 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 \fIdnsclass\fP and \fItype\fP give the class and type of the +query using the values defined in \fB<arpa/nameser.h>\fP. + +The parameter \fIid\fP gives a 16-bit identifier for the query. + +The parameter \fIrd\fP 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 \fIbuf\fP, and the length of which will +be stored in the variable pointed to by \fIbuflen\fP. + +It is the caller's responsibility to free this buffer using +\fIares_free_string(3)\fP when it is no longer needed. The parameter +\fImax_udp_size\fP should be nonzero to activate EDNS. Usage of +\fIares_create_query(3)\fP\ with \fImax_udp_size\fP set to zero is equivalent +to using \fIares_mkquery(3)\fP. +.SH RETURN VALUES +.B ares_create_query +can return any of the following values: +.TP 15 +.B ARES_SUCCESS +Construction of the DNS query succeeded. +.TP 15 +.B ARES_EBADNAME +The query name +.I 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. +.TP 15 +.B ARES_ENOMEM +Memory was exhausted. +.SH AVAILABILITY +Added in c-ares 1.10.0 +.SH SEE ALSO +.BR ares_expand_name (3), +.BR ares_free_string (3), +.BR ares_mkquery (3) +.SH AUTHOR |