Process reapers

[Konstantin Belousov]

On Mon, Dec 01, 2014 at 02:43:17PM -0800, Rui Paulo wrote:
> One comment I have is that we could rename the variables to something more meaningful instead of "p1" or "p2".  If "p1" is the reaper, we could call it "p_reaper".
> 
p_reaper is too confusing even to write, it is the same as the name
of the struct proc member.  p1/p2 is the pattern used in dofork(), so
I followed it for new code.

I could rename p1 to something else, but also short, since LIST_*
constructs are long and clumsy.  Might be, s/p1/rp/ ?