It seems to me that only the IP_PKTINFO is relevant.
and it can be used, for example, to set an IP address that is used as the s= ource IP when packets are sent out when using a UDP socket.
The others options are not relavant/not ancillary:
IP_RECVERR - for recvmsg()=20
IP_RECVOPTS - not ancillary
(setsockopt (sock, IPPROTO_IP, IP_RECVOPTS, (char *)&on, IP_RECVORIGDSTADDR - recvmsg
IP_RECVTOS - incoming packets.
IP_ROUTER_ALERT - Only valid for raw sockets
IP_TOS,IP_TRANSPARENT,IP_TTL,IP_UNBLOCK_SOURCE - not ancillar=
Am I right about it ?=20
On Monday, August 26, 2013 11:11:14 AM UTC+3, Richard Kettlewell wrote: