strongswan_subnetof(3) - Linux man page
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.