lwres_getrrsetbyname.3 revision 8a66318e41ed14c5a88130e8c362610e8faa2121
Copyright (C) 2004 Internet Systems Consortium, Inc. ("ISC")
Copyright (C) 2000, 2001 Internet Software Consortium.

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purpose with or without fee is hereby granted, provided that the above
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REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
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$Id: lwres_getrrsetbyname.3,v 1.13 2004/03/05 08:32:20 marka Exp $

"LWRES_GETRRSETBYNAME" "3" "Oct 18, 2000" "BIND9" ""
NAME
lwres_getrrsetbyname, lwres_freerrset - retrieve DNS records
SYNOPSIS
#include <lwres/netdb.h> int lwres_getrrsetbyname(const char *hostname, unsigned int rdclass, unsigned int rdtype, unsigned int flags, struct rrsetinfo **res); void lwres_freerrset(struct rrsetinfo *rrset);

The following structures are used: 

struct rdatainfo {
 unsigned int rdi_length; /* length of data */
 unsigned char *rdi_data; /* record data */
};

struct rrsetinfo {
 unsigned int rri_flags; /* RRSET_VALIDATED... */
 unsigned int rri_rdclass; /* class number */
 unsigned int rri_rdtype; /* RR type number */
 unsigned int rri_ttl; /* time to live */
 unsigned int rri_nrdatas; /* size of rdatas array */
 unsigned int rri_nsigs; /* size of sigs array */
 char *rri_name; /* canonical name */
 struct rdatainfo *rri_rdatas; /* individual records */
 struct rdatainfo *rri_sigs; /* individual signatures */
};
"DESCRIPTION"

lwres_getrrsetbyname() gets a set of resource records associated with a hostname, class, and type. hostname is a pointer a to null-terminated string. The flags field is currently unused and must be zero.

After a successful call to lwres_getrrsetbyname(), *res is a pointer to an rrsetinfo structure, containing a list of one or more rdatainfo structures containing resource records and potentially another list of rdatainfo structures containing SIG resource records associated with those records. The members rri_rdclass and rri_rdtype are copied from the parameters. rri_ttl and rri_name are properties of the obtained rrset. The resource records contained in rri_rdatas and rri_sigs are in uncompressed DNS wire format. Properties of the rdataset are represented in the rri_flags bitfield. If the RRSET_VALIDATED bit is set, the data has been DNSSEC validated and the signatures verified.

All of the information returned by lwres_getrrsetbyname() is dynamically allocated: the rrsetinfo and rdatainfo structures, and the canonical host name strings pointed to by the rrsetinfostructure. Memory allocated for the dynamically allocated structures created by a successful call to lwres_getrrsetbyname() is released by lwres_freerrset(). rrset is a pointer to a struct rrset created by a call to lwres_getrrsetbyname().

"RETURN VALUES"

lwres_getrrsetbyname() returns zero on success, and one of the following error codes if an error occurred:

ERRSET_NONAME the name does not exist

ERRSET_NODATA the name exists, but does not have data of the desired type

ERRSET_NOMEMORY memory could not be allocated

ERRSET_INVAL a parameter is invalid

ERRSET_FAIL other failure

"SEE ALSO"

lwres(3).