IPSEC_SUBNETOF(3)

NAME
ipsec subnetof - given Internet address and subnet mask, return subnet number
ipsec hostof - given Internet address and subnet mask, return host part
ipsec broadcastof - given Internet address and subnet mask, return broadcast address

SYNOPSIS
#include <freeswan.h>

struct in_addr subnetof(struct in_addr addr,
struct in_addr mask);
struct in_addr hostof(struct in_addr addr,
struct in_addr mask);
struct in_addr broadcastof(struct in_addr addr,
struct in_addr mask);

DESCRIPTION
These functions are obsolete; see ipsec_networkof(3) for their replacements.

Subnetof takes an Internet address and a subnet mask and returns the network part of the address (all in network byte order). Hostof similarly returns the host part, and broadcastof returns the broadcast address (all-1s convention) for the network.

These functions are provided to hide the Internet bit-munging inside an API, in hopes of easing the eventual transition to IPv6.

SEE ALSO
inet(3), ipsec_atosubnet(3)

HISTORY
Written for the FreeS/WAN project by Henry Spencer.

BUGS
Calling functions for this is more costly than doing it yourself.