Control: reassign -1 apt Control: retitle -1 apt: should use selections instead of --force-* options
[ This is actually something I've had in my list of things to discuss with frontends, so here it goes, through a bug report. :) ] On Sat, 2010-07-17 at 06:59:38 -0500, Jonathan Nieder wrote: > Moritz Beyreuther wrote: > > /usr/bin/dpkg --status-fd 11 --force-depends --force-remove-essential > > --remove courier-mta courier-base courier-authdaemon courier-authlib-userdb > > courier-authlib > > > > However courier-authlib is deinstalled first which breaks the > > deinstallation process as explained in 579790. > > exim is being installed to replace courier-mta as mail-transfer-agent. > As you mentioned, bsd-mailx depends on an mta, so there is apparently > no clean way to do this and the frontend passes a --force-* option. > So now from the point of view of dpkg we are outside the realm of > policy and in my opinion no matter what happens it is not going to be > intuitive. > > There is a way around that, which is to use the --auto-deconfigure > option. It should be able to produce a saner sequence of operations: > > 1. deconfigure everything that needs an mta > 2. remove courier-mta > 3. remove the packages courier-mta depended on Nope, the correct way to go about this is to setup a “dpkg transaction” through selections, which tells explicitly to dpkg what can be done, avoids the extra scary message from dpkg, gets a better result, minimizes the time packages have been forced out of the way, and avoids --force-* options. In this case apt would do, the equivalent of: # cat <<TRANS | dpkg --set-selections courier-mta deinstall courier-base deinstall courier-authdaemon deinstall courier-authlib-userdb deinstall courier-authlib deinstall TRANS # dpkg --auto-deconfigure --install exim*.deb # dpkg --remove --pending or something similar. In general apt should really not be forcing removals on dpkg, it should tell dpkg what packages are fine to remove, and then do a final remove, that would also reduce the number of transactions needed for an upgrade. The only --force option that a frontend should be “justified” to use at all is --force-remove-essential, only when the user has acknowledged that explicitly through a prompt or similar, and only then, not passed blindly on all invocations. In general, any time a frontend is using a --force option, there's something wrong going on. Using selections is how dselect has managed to work all this time w/o the need for any --force option at all. Thanks, Guillem -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
