Bug#328291: debconf, tex-common and the management of ls-R and .cnf files

[Frank Küster <frank@kuesterei.ch>]

Norbert Preining <preining@logic.at> wrote:

> What we could do is ask for "Which ls-R file do you want to manage with
> debconf" and suggest/default to /v/c/f and TEXMFLOCAL. So we would have
> one question with multiselect which replaces the "DO you want to manage
> with debconf" question, and the others about perm/group.
>
> Would this be more useful? Do you prefer this?

Yes, that sounds best to me.

> Hmmm. As far as I udnerstood the manpage of debconf-devel there not
> necessarily is! The default is *not* saved in the debconf db:
>
> man debconf-devel:
>        Default
> 	      [...]
>               Don't  make  the mistake of thinking that the default field con-
>               tains the "value" of the question, or that it  can  be  used  to
>               change  the  value  of the question. It does not, and cannot, it
>               just provides a default value for the first time the question is
>               displayed.  To  provide a default that changes on the fly, you'd
>               have to use the SET command to change the value of a question.
>
> But this does not happen in the config/postinst scripts of tetex-bin. So
> I guess there not ncessarily is an answer in the debconf db.

I still think there is, because of the following reason:  If the
question is registered at all, this means that tetex-bin was installed,
and consequently that its config script was run.  In this case either
the question was shown (so we have an answer) or it wasn't shown due to
priority or frontend settings, in which case the default will have been
taken (and consequently written to the database).  The postinst script
would then get the default when it asks - otherwise postinst scripts
would have to cater explicitly for noninteractive installs.  If you
get an empty return value you know tetex-bin wasn't installed; you could
also check for this.

Since there is no way to ask debconf whether a particular question is
registered (except checking the return value, but I think this is
undocumentend and therefore subject to change), I guess we have to use
either fget on the seen flag or check for empty/nonempty return value.

>> Also, don't forget to set the "seen" flag to yes for the tex-common
>> incarnation of the question it it was already seen in tetex.
>
> Ok, I will change this (although I would prefer it to see the question
> when it moves to tex-common).

Why do you think people would decide otherwise just because a different
package is managing the files?  Well, but in fact we change the options
of the question, and this makes it worth showing it again.  I see two
possible options for us:

- either disregard tetex-bin's answer to the "manage with debconf"
  question completely, and only look at the values for
  groupname/userperm/groupperm when the answer to the new question is
  yes 

- or look at tetex-bin's setting and set our question to "no" if the
  answer to tetex-bin was also no, otherwise keep our default (fonts and
  TEXMFLOCAL), and then ask our question.

Regards, Frank
-- 
Frank Küster
Inst. f. Biochemie der Univ. Zürich
Debian Developer