cvs commit: src/etc rc.subr

[Yar Tikhiy]

On Tue, Jul 25, 2006 at 10:27:49PM -0700, Doug Barton wrote:
> Yar Tikhiy wrote:
> > yar         2006-07-25 17:20:22 UTC
> > 
> >   FreeBSD src repository
> > 
> >   Modified files:
> >     etc                  rc.subr 
> >   Log:
> >   Avoid extra runs of test(1) by using its built-in logical operations.
> >   
> >   Revision  Changes    Path
> >   1.63      +9 -15     src/etc/rc.subr
> > 
> > http://www.FreeBSD.org/cgi/cvsweb.cgi/src/etc/rc.subr.diff?&r1=1.62&r2=1.63&f=h
> 
> I'm pretty sure that this commit has the opposite effect from what you
> intended. If you do:
> 
> [ foo -a bar ]
> 
> then the bar test will always be run, whereas if you do
> 
> [ foo ] && [ bar ]
> 
> bar won't run unless foo succeeds.

I believed test(1) was smarter than that.  But as a matter of fact,
-a won't skip bar even if foo is false, neither will -o if foo is
true.  Is this a bug or a required feature?

> Also, you should be aware that in our /bin/sh test is a builtin, so what
> you're trying to optimize for is not actually an issue to start with.

I admit that I was under the opposite impression that test(1) is
external to our sh(1).  Perhaps our sh(1) manpage didn't state that
clearly enough.  (Just clarified it.)  Anyway, I should have looked
at builtin(1), it said the truth.

> Unless you can show that this commit actually does improve performance, I'd
> appreciate it if you'd reverse it.

No objection!  Fetched my back-out tool and gone applying it...

-- 
Yar