NAME

dn_find − Search for an expanded domain name

SYNOPSIS

#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h> int dn_find(
        char ∗exp_domain_name,
        char ∗message,
        char ∗∗domain_names,
        char ∗∗end_ptr );

LIBRARY

Standard C Library (libc)

PARAMETERS

exp_domain_name
Points to an expanded domain name.

message
Points to the address of a domain name message that contains the name sought by the dn_find() function. 

domain_names
Specifies an array of pointers to previously compressed names in the current message.

end_ptr
Points to the end of an array of pointers.  The array is indicated by the domain_names parameter. 

DESCRIPTION

The dn_find() (domain name find) function searches for an expanded domain name from a list of previously compressed names. An application program calls the dn_find() function indirectly using the dn_comp() function. If an expanded domain name is found, the dn_comp() function returns the offset from the message parameter. 

The dn_find() function is one of a set of subroutines that form the resolver, a set of functions that resolves domain names.  Global information used by the resolver functions resides in the _res data structure.  The include/resolv.h file contains the _res data structure definition. 

RETURN VALUES

Upon successful completion, the dn_find() function returns the offset from the message parameter. Otherwise, the dn_find() function returns a value of -1. 

FILES

/etc/resolv.conf
Defines name server and domain name structures and constants.

SEE ALSO

Functions: res_init(3), res_mkquery(3), res_send(3), dn_comp(3), dn_expand(3), _getshort(3), _getlong(3), putshort(3), putlong(3), dn_skipname(3)

Commands: named(8)