.\" The "BSD-New" License .\" .\" Copyright (c) 2013, NLnet Labs, Verisign, Inc. .\" All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" * Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" * Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" * Neither the names of the copyright holders nor the .\" names of its contributors may be used to endorse or promote products .\" derived from this software without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED .\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE .\" DISCLAIMED. IN NO EVENT SHALL Verisign, Inc. BE LIABLE FOR ANY .\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES .\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; .\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND .\" ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS .\" SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. .\" .TH getdns_general 3 "December 2015" "getdns 1.6.0" getdns .SH NAME .B getdns_general, .B getdns_general_sync -- do a getdns DNS lookup .SH LIBRARY DNS Resolver library (libgetdns, \-lgetdns) .SH SYNOPSIS #include getdns_return_t .br .B getdns_general (getdns_context *context, .RS 3 const char *name, .br uint16_t request_type .br getdns_dict *extensions, .br void *userarg, .br getdns_transaction_t *transaction_id, .br getdns_callback_t callbackfn) .RE getdns_return_t .br .B getdns_general_sync (getdns_context *context, .RS 3 const char *name, .br uint16_t request_type .br getdns_dict *extensions, .br getdns_dict **response) .RE .SH DESCRIPTION .LP The getdns_general(3) and getdns_general_sync functions provide public entry points into the getdns API library to retrieve any valid responses to a query from the DNS (note that other namespaces in the context are not used). Most typical use cases for applications are probably satisfied via calls to getdns_address(3) which would replace getaddrinfo(3). .HP 3 .I context A pointer to the previsouly created DNS context that is to be used with this DNS request. see getdns_context (3) .HP 3 .I name The ASCII-based domain name looked up as a string. This can also be an IPv4 or IPv6 address for request types that take addresses instead of domain names, such as PTR. The values here follow the rules in section 2.1 of RFC 4343 to allow non-ASCII octets and special characters in labels. .HP 3 .I request_type Specifies the RRtype for the query; the RRtype numbers are listed in the IANA registry. For example, to get the NS records, request_type would be 2. The API also has defined macros for most of the RRtypes by name; the definition names all start with "GETDNS_RRTYPE_". For example, to get the NS records, you can also set the request_type to GETDNS_RRTYPE_NS. .HP 3 .I extensions extensions for this request, NULL if no extensions, see libgetnds (3) for a detailed description of extensions .HP 3 .I userarg returned to the callback function untouched, can be NULL .HP 3 .I transaction_id populated by the API and used to identify the callback (for example to getdns_cancel_callback), can be NULL, set to 0 if the function fails .HP 3 .I callbackfn non-NULL pointer to a callback function defined by the application, typically used to process the response. Only the asynchronous signature accepts a callback function, the synchronous signature does not include a callback. See libgetdns (3) for a more detailed discussion of callback functions. .HP 3 .I response A getdns_dict type is returned in response and always contains at least three names: replies_full (a list containing the DNS response as binary data), replies_tree (a list containing the parsed DNS response data) and status (an int). The storage associated with this must be freed by a call to getdns_free_sync_request_memory (3). .HP .SH "RETURN VALUES" Upon successful completion the functions return .B GETDNS_RETURN_GOOD , otherwise the following error values are returned: .LP .B GETDNS_RETURN_BAD_CONTEXT if the context pointer is invalid or the context has internal deficiencies .LP .B GETDNS_RETURN_BAD_DOMAIN_NAME if the domain name passed to the function is invalid .LP .B GETDNS_RETURN_EXTENSION_MISFORMAT if the data type specified in one or more of the extensions does not match the specifications .LP .B GETDNS_RETURN_GENERIC_ERROR if some problem was encountered in the function not addressed by one of the more specific return codes .LP .B GETDNS_RETURN_INVALID PARAMETER if one or more parameters has an invalid value .LP .B GETDNS_RETURN_MEMORY_ERROR if unable to allocate the memory required .LP .B GETDNS_RETURN_NO_SUCH_EXTENSION if one or more of the strings specified in the extensions are not valid The values of status included in the response parameter are: .LP .B GETDNS_RESPSTATUS_GOOD if at least one response was returned .LP .B GETDNS_RESPSTATUS_NO_NAME if queries for the name yielded all negative responses .LP .B GETDNS_RESPSTATUS_ALL_TIMEOUT if all queries for the name timed out .LP .B GETDNS_RESPSTATUS_NO_SECURE_ANSWERS if only secure replies accepted (per context) and at least one response was received but no DNS responses were secure through DNSSEC .LP For a more detailed explanation of the response object see .I libgetdns (3) .SH REQUEST TYPES This is a list of the most common request types, a full list of request types in more detail is available at http://www.iana.org/assignments/dns-parameters/dns-parameters.xml .RS 3 .TP 11 .B A Host address .TP .B AAAA IPv6 address .TP .B CAA Certificate Authority Authorization .TP .B CNAME Canonical name for an alias .TP .B DLV DNSSEC lookaside validation .TP .B DNAME DNAME .TP .B DS Delegation signer .TP .B HINFO Host information .TP .B KEY Security key .TP .B MINFO Mailbox or mail list information .TP .B MX Mail exchange .TP .B NS Authoritative name server .TP .B NSEC Next secure record .TP .B NSEC3 Next secure record (hashed) .TP .B NSEC3PARAM NSEC3PARAM .TP .B PTR Domain name pointer .TP .B RRSIG Signature for a record set .TP .B SIG Security signature .TP .B SOA Marks the start of a zone of authority .TP .B SRV Server selection .TP .B TA DNSSEC trust authorities .TP .B TKEY Transaction key .TP .B TLSA TLSA .TP .B TSIG Transaction signature .TP .B TXT Text strings .RE .SH EXAMPLES TBD .SH FILES .br /etc/hosts .br /etc/resolv.conf .SH SEE ALSO .BR libgetdns (3), .BR getdns_address (3), .BR getdns_context (3), .BR getdns_free_sync_request_memory (3), .BR getdns_hostname (3), .BR getdns_service (3),