Ideas for the upstart migration for /sbin/init in Debian

[Sven Joachim]

On 2009-09-15 23:32 +0200, Michael Biebl wrote:

> Petter Reinholdtsen wrote:
>> 
>> Another idea that was discussed on IRC was to change the sysvinit
>> package to become a dummy package depending on something like
>> upstart|sysvinit-legacy, and move all files from sysvinit to
>> sysvinit-legacy.  For kfreebsd and hurd where upstart do not work, the
>> dummy package would depend only on sysvinit-legacy for now.  This
>> would hopefully make sure dist-upgrade change existing installations
>> to upstart.

Is it possible to make sysvinit-legacy "Essential: yes" only on
non-Linux architectures?  If not, there needs to be a different name for
it on those architectures.

> I think this is the more promising idea of those two.
> Still need to check, if we can avoid the dpkg prompt, about removing an
> Essential package. Say we change sysvinit to a dummy, non-essential package in
> versionA, upstart still needed to have a Conflicts/Replaces: sysvinit (<<
> versionA) I guess.

I don't see why you couldn't just use Replaces without Conflicts.  The
new dummy sysvinit package has to Pre-Depend on upstart anyway, so that
/sbin/init does not temporarily vanish from the system.

Speaking of Pre-Depends, upstart needs to use them as well as soon as it
becomes "Essential: yes" (see Policy §3.8).

Sven