NetBSD/dist/ntp/libntp/netof.c

28 lines
506 B
C

/* $NetBSD: netof.c,v 1.1.1.1 2000/03/29 12:38:50 simonb Exp $ */
/*
* netof - return the net address part of an ip address
* (zero out host part)
*/
#include <stdio.h>
#include "ntp_fp.h"
#include "ntp_stdlib.h"
u_int32
netof(
u_int32 num
)
{
register u_int32 netnum;
netnum = num;
if(IN_CLASSC(netnum))
netnum &= IN_CLASSC_NET;
else if (IN_CLASSB(netnum))
netnum &= IN_CLASSB_NET;
else /* treat all other like class A */
netnum &= IN_CLASSA_NET;
return netnum;
}