ipsec_subnetof (3) Linux Manual Page

ipsec_subnetof, ipsec_hostof, ipsec_broadcastof – given Internet address and subnet mask return subnet number, host part, broadcast address

Synopsis

#include <libreswan.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.