_res value related query

[Channa <channa.kad%gmail.com@localhost>]

Hi,

I have a query with respect to '_res' resolver state in NetBSD.
Which is define in resolv.h as

$ cat include/resolv.h

:
#define _res (*__res_state())
:

The have the following test case.

#include <stdio.h>
#include <resolv.h>
#include <netdb.h>

int main(int argc,char *argv[])
{
  printf("The _res value is %d\n",_res);

  return 0 ;
}

when executed gives the following output:

$ ./test
The _res value is 5

It always prints the value '5'.
Could anyone tell me why the value 5??

Thanks & Regards,
Channa