struct sk_buff * skb_peek
(struct sk_buff_head * list_);
Peek an &sk_buff. Unlike most other operations you _MUST_
be careful with this one. A peek leaves the buffer on the
list and someone else may run off with it. You must hold
the appropriate locks or have a private queue to do this.
Returns NULL for an empty list or a pointer to the head element.
The reference count is not incremented and the reference is therefore
volatile. Use with caution.