[CFT] multiple instance support in rc.d script

[Mark Felder]

On Wed, Oct 22, 2014, at 12:02, Jim Riggs wrote:
> On 16 Oct 2014, at 20:22, Hiroki Sato <hrs at FreeBSD.org> wrote:
> 
> > I would like your feedback and testers of the attached patch.  This
> > implements multiple instance support in rc.d scripts.  You can try it
> > by replacing /etc/rc.subr with the attached one.
> 
> 
> I really like the idea, as I have written at least 2 or 3 ports in which
> I have needed support for multiple "profiles" (as I have seen them called
> in several ports). So, I had to duplicate the multiple-instance logic in
> the rc script for each. This would save all of that aggravation.
> 
> The only concern I have with generalizing the approach in rc.subr,
> though, is that not every app/daemon/script can or should support it. I
> worry that some things if run multiple times may stomp on each other or
> corrupt data or break something. It seems that there should be a way for
> each rc script to either opt in or opt out of multiple instance support.
> I don't know which is better. Opt-in is probably safer, but then core
> devs and port maintainers have to make specific changes to support it.
> :-\
> 
> Thoughts?
>

I would definitely prefer opt-in. We don't want to break things or lose
users' data; POLA.

After the feature is available users can request support if the
maintainers aren't already working on it.