IP_ROUTER_ALERT2const
Pass all to-be forwarded packets
Usage
#include <netinet/in.h> /* Definition of IP* constants */ #include <sys/socket.h>
int setsockopt(int sockfd, IPPROTO_IP, IP_ROUTER_ALERT, const int *enable, sizeof(int));
Library
Standard C library (libc, -lc)
Overview
Pass all to-be forwarded packets with the IP Router Alert option set to this socket.
Valid only for raw sockets.
This is useful, for instance, for user-space RSVP daemons.
Errors
See IPPROTO_IP(2const). See setsockopt(2). See ip(7).
Caveats
The tapped packets are not forwarded by the kernel; it is the user's responsibility to send them out again.
Socket binding is ignored, such packets are filtered only by protocol.