Re: NLMSG_* macros (was: Re: ULOG comments)

[Jan Echternach <echter@xxxxxxxxxxxxxxxxxxxxxxxxx>]

On Wed, Aug 16, 2000 at 12:26:50PM +0200, Andi Kleen wrote:
> nlmsghdr has other uses than just handling multipart messages. For 
> examples it gives you a sequence number so that you can try to detect
> lost packets and a way to request acks.
> netlink sockets require a nlmsghdr

NETLINK_NFLOG packets originate in the kernel.  Packet loss is signaled
by ENOBUFS, and resending of packets is impossible unless the kernel is
willing to eat huge amounts of memory before finally stopping all
networking whenever an application decides to stop reading from the
socket.

> > Should NLMSG_* be used on the new NETLINK_NFLOG socket?
> 
> Definitely. 

Ok, I'll use NLMSG_* for my iptables targets, because I'm out of
arguments against it, even though I still don't see how any feature of
nlmsghdr could be used by NETFILTER_NFLOG that isn't provided by a
plain C structure in a simpler way.

-- 
Jan