dn_expand(3) — Subroutines
OSF
NAME
dn_expand − Expands a compressed domain name
LIBRARY
Standard C Library (libc.a)
SYNOPSIS
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>
int dn_expand (
u_char ∗message_ptr,
u_char ∗end_of_message,
u_char ∗compressed_name,
u_char ∗expanded_name,
int length );
PARAMETERS
message_ptrSpecifies a pointer to the beginning of a message.
end_of_message
Points to the end of the original message that contains the compressed domain name.
compressed_name
Specifies a pointer to a compressed domain name.
expanded_name
Specifies a pointer to a buffer that holds the resulting expanded domain name.
lengthSpecifies the size of the buffer pointed to by the expanded_name parameter.
DESCRIPTION
The dn_expand() function expands a compressed domain name to a full domain name, converting the expanded names to uppercase.
The dn_expand() function is one of a set of subroutines that form the resolver, a set of functions that resolves domain names. Global information that is used by the resolver functions is kept in the _res data structure. The /include/resolv.h file contains the _res structure definition.
RETURN VALUES
Upon successful completion, the dn_expand() function returns the size of the expanded domain name. Otherwise, a value of -1 is returned.
FILES
/etc/resolv.conf
Defines name server and domain name constants, structures, and values.
RELATED INFORMATION
Functions: res_init(3), res_mkquery(3), res_send(3), dn_comp(3), dn_find(3), getshort(3), getlong(3), putshort(3), putlong(3), dn_skipname(3)