dn_expand()

Expand a compressed Internet domain name

Synopsis:

#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>

int dn_expand( const u_char* msg, 
               const u_char* eomorig, 
               const u_char* comp_dn, 
               u_char* exp_dn, 
               int length );

Library:

libsocket

Description:

The dn_expand() function is a low-level routine used by res_query() to expand the compressed domain name, comp_dn, to a full domain name.

The compressed name is contained in a query or reply message; msg is a pointer to the beginning of the message. The eomorig argument is a pointer to the first location after the message.

The uncompressed name is placed in the buffer indicated by exp_dn; the size of the buffer is specified by length.

Returns:

The size of the compressed domain name, in bytes, or -1 if an error occurs.

Classification:

Unix

Safety:
Cancellation point	No
Interrupt handler	Yes
Signal handler	Yes
Thread	Yes