Re: Proposed release goal: Switch to dash as /bin/sh to speed up the boot

[Petter Reinholdtsen <pere@hungry.com>]

[Thorsten Glaser]
> First of, this is already possible, so that wouldn't be a change,
> just keeping currently existing behaviour.

Exactly.  So no really need to make it _easier_ to use anything except
dash, as dash is proven to speed up the boot by at least 7%.  None of
the others have documented the same or better.

> Second, Debian policy states that /bin/sh can be any POSIX compatible
> shell, not just GNU bash and dash. So you'd have to change the policy
> to forbid people to install mksh, pdksh, AT&T ksh, whatever as /bin/sh.

Nope.  I do not have to change policy at all, as my proposal is to
speed up the boot by replacing bash with dash as /bin/sh, not to
prohibit anyone from messing with /bin/sh on their own machine.

> This way, portability problems in scripts can be found easier, as can
> possible bugs (or non-bug issues) in the shells. (The next major version
> of mksh will not define “stop” as a shell alias any longer if it's called
> as -sh or */sh to prevent more bugs like #424213 to be filed.)

Sure, finding portability problems is a good goal, and I hope you or
anyone else will work on that.  But I also hope you see that it is a
different goal from speeding up the boot system, and in no way a
requirement for speeding up the boot.

> Please consider keeping current policy and implementing the
> alternatives system like the window manager stuff in the Debconf
> tutorial.

I believe the reason /bin/sh replacment isn't done using alternatives
it to reduce the possibility of leaving the system completely wracked
if something goes wrong with the alternatives.  At least that was the
argument I heard when it was proposed last time.

Happy hacking,
-- 
Petter Reinholdtsen