Re: wait(2) and SIGCHLD

[David Holland <dholland-tech%netbsd.org@localhost>]

On Sat, Aug 15, 2020 at 07:57:26PM -0400, Terry Moore wrote:
 > >> I would say so, especially since that would mean the child's parent is
 > >> no longer the process that forked it (which could break other use
 > >> cases).
 > >
 > > That depends on how you implement detaching, but I suppose ultimately
 > > it's important for getppid() to revert to 1 at the point the parent
 > > exits (neither before, nor after, nor never) so some kind of linkage
 > > needs to remain.
 > >
 > > Bah.
 > >
 > > I guess it's time to invent yet another different interface to
 > > fork-and-really-detach.
 > 
 > No time to experiment today, but from the descriptions it sounds as if a
 > double fork would work,
 > with the child exiting immediately after forking the grandchild? Kind of
 > unpleasant, but nothing
 > new needed?

(For the record: yes, forking twice works, that's more or less the
standard approach; but it's comparatively expensive.)

-- 
David A. Holland
dholland%netbsd.org@localhost