Re: Improving in-place upgrades of Ada packages from Lenny to Squeeze
David Kalnischkies wrote:
2010/5/31 Ludovic Brenta <email@example.com>:
Option 1: upload a new package "gnat" that Breaks: all
-dev packages that were present in Lenny but are no
longer present in Squeeze. This however does not really
help apt, or the user, discover the new replacement
Option 2: change each new -dev package so that it Breaks:
its predecessor. For example, let libgtkada2.14.2-dev
As far as i understand can the old lib-packages not be used with
the new gnat. Right?
If so i would say gnat should Break them. Breaking them
in the new-libs will not help as the new-libs still need
to be installed to get the Breaks effect - and they are
With the break you can force the update of old-libs, which
could depend in their new version on the new-libs.
I don't see another route to install the new-libs, but
1. Is this really needed? If the user needs them they are an
apt-get install (or similar) away. new-lib isn't a drop-in
replacement for old-lib (or?) and (s)he therefore
needs to learn a new way anway?
In most cases new-lib is a perfect replacement for old-lib,
so getting new-lib installed where old-lib was installed is
definitely preferable to have to install it manually.
2. the old-libs will stay installed in at least of the
form of a transitional package in oldlibs as at least
apt/lenny has no support for disappear packages so this
trick can't be used (not sure about dpkg, aptitude uses
apt facility in this regard, so also no support).
This is ugly, but not horrible.
Question 2: if I add Breaks: to a -dev package, which
ones of Conflicts: and Replaces: should I also specify?
(currently, both are specified; the new packages replace
almost all files of the old packages).
You want only Breaks or Conflicts. Breaks is in general
the nicer Conflict - in some way they are the negative
version of Depends and Pre-Depends: Conflicts must be
satisfied before the package is unpacked - so both
packages can't be in unpack (or higher) at the same time,
while Breaks only says that both can't be in installed at
the same time.
So if there are common files, conflicts is required?
"I have no prejudice except against Pakistanis, which is normal."