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       lwres_getrrsetbyname, lwres_freerrset - retrieve DNS records


       #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 */


       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().


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

           the name does not exist

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

           memory could not be allocated

           a parameter is invalid

           other failure




       Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc.
       Copyright (C) 2000, 2001 Internet Software Consortium.