prerm/postrm considered harmful in M-A: same packages

[Josselin Mouette <joss@debian.org>]

Hi,

I noticed a problem with several packages when they were migrated to
multiarch, and I’m afraid we have a pattern here.

Here, libfoo is a Multi-Arch: same package.

libfoo.postinst:
 → Generate /etc/libfoo.conf
 → Modify /etc/bar.conf to add libfoo support (think typically NSS
modules)
The postinst is idempotent, so applying it once per installed
architecture is no problem.

libfoo.prerm or postrm (in remove or purge cases):
 → Remove /etc/libfoo.conf
 → Remove mentions to libfoo in /etc/bar.conf
You remove the package for one architecture, and it stops working for
the other installed architectures.

This is of course another good reasons to use triggers everywhere we
can, but the question is: is there a way we can detect such problems
with lintian?

-- 
 .''`.        Josselin Mouette
: :' :
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