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73 lines
2.3 KiB
73 lines
2.3 KiB
.\" |
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.\" Copyright 1998 by the Massachusetts Institute of Technology. |
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.\" SPDX-License-Identifier: MIT |
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.\" |
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.TH ARES_CREATE_QUERY 3 "17 Aug 2012" |
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.SH NAME |
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ares_create_query \- Compose a single-question DNS query buffer |
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.SH SYNOPSIS |
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.nf |
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#include <ares.h> |
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int ares_create_query(const char *\fIname\fP, |
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int \fIdnsclass\fP, |
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int \fItype\fP, |
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unsigned short \fIid\fP, |
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int \fIrd\fP, |
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unsigned char **\fIbuf\fP, |
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int *\fIbuflen\fP, |
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int \fImax_udp_size\fP) |
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.fi |
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.SH DESCRIPTION |
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The \fIares_create_query(3)\fP function composes a DNS query with a single |
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question. The parameter \fIname\fP gives the query name as a NUL-terminated C |
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string of period-separated labels optionally ending with a period; periods and |
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backslashes within a label must be escaped with a backlash. |
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The parameters \fIdnsclass\fP and \fItype\fP give the class and type of the |
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query using the values defined in \fB<arpa/nameser.h>\fP. |
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The parameter \fIid\fP gives a 16-bit identifier for the query. |
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The parameter \fIrd\fP should be nonzero if recursion is desired, zero if not. |
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The query will be placed in an allocated buffer, a pointer to which will be |
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stored in the variable pointed to by \fIbuf\fP, and the length of which will |
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be stored in the variable pointed to by \fIbuflen\fP. |
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It is the caller's responsibility to free this buffer using |
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\fIares_free_string(3)\fP when it is no longer needed. The parameter |
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\fImax_udp_size\fP should be nonzero to activate EDNS. Usage of |
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\fIares_create_query(3)\fP\ with \fImax_udp_size\fP set to zero is equivalent |
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to using \fIares_mkquery(3)\fP. |
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.SH RETURN VALUES |
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.B ares_create_query |
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can return any of the following values: |
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.TP 15 |
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.B ARES_SUCCESS |
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Construction of the DNS query succeeded. |
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.TP 15 |
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.B ARES_ENOTFOUND |
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The query name |
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.I name |
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refers to a |
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.I .onion |
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domain name. See RFC 7686. |
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.TP 15 |
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.B ARES_EBADNAME |
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The query name |
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.I name |
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could not be encoded as a domain name, either because it contained a |
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zero-length label or because it contained a label of more than 63 |
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characters. |
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.TP 15 |
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.B ARES_ENOMEM |
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Memory was exhausted. |
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.SH AVAILABILITY |
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Added in c-ares 1.10.0 |
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.SH SEE ALSO |
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.BR ares_dns_record (3), |
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.BR ares_expand_name (3), |
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.BR ares_free_string (3), |
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.BR ares_mkquery (3) |
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.SH AUTHOR
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