Re: A question about netlink_broadcast()

["MHD.Tayseer Alquoatli" <idoit.ief@xxxxxxxxx>]

On 6/3/06, cheng long <kevinclcn@xxxxxxxxx> wrote:

Hi, All !
int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 pid,
                                u32 group, int allocation);

What does the pid mean? Someone said that it is the pid of the receiver.
For example, Kevin He said it delivers a netlink message to both the
process specified by pid and the multicast groups specified by group
(http://www.linuxjournal.com/article/7356.)

But, in function do_one_broadcast() which is called in netlink_broadcast(),
there are some sentences like this:

744  struct netlink_opt *nlk = nlk_sk(sk);
750  if (nlk->pid == p->pid || !(nlk->groups & p->group))
751            goto out;

where p is a variable constructed from parameters of netlink_broadcast().

I think these sentences mean that the parameter pid of netlink_broadcast()
is the sender's pid?

Hi Cheng
no it isn't .. it's the receiver pid. this is an excerpt from the article you've pointed to:
"You also can send a multicast message. The following API delivers a netlink message to both the process specified by pid and the multicast groups specified by group:"
hope this helps

Am I right?

Thanks !

Regard,
Cheng

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