[sclug] [OT] Where does apt keep its list of installed software?

[Dickon Hood]

On Tue, Oct 25, 2011 at 15:16:33 +0100, Ian Park wrote:
: Hi all

: I'm afraid I've rather sawn off the branch I was sitting on...

: I updated my Acer Aspire One to the latest version of Ubuntu ("Oneiric
: Ocelot", v11.10) and found that I could no longer boot into the classic
: Ubuntu interface(I dislike Unity). I made the mistake of applying some
: tweaks to get back to the classic Gnome interface and re-booted, only to
: find that it now hangs at the Ubuntu splash screen. I'd more or less
: made up my mind to install Debian Squeeze and junk Ubuntu, but I really
: want to back up the list of apps I'd installed. All the searching I've
: done has led me to instructions on how to use apt-get or Synaptic to
: produce a list of installed software, but that isn't a lot of help if I
: can't boot into the Ubuntu system...

: I have a USB CD writer/DVD reader drive, so I've been able to boot a
: live version of Debian, but the problem is I don't know where to find
: the file in the Ubuntu filesystem which stores the list of installed
: software. Can anyone help please?

Mount your filesystems somewhere, chroot into it, "dpkg --get-selections |
grep ' installed' > /tmp/installed", leave the chroot, copy that file
somewhere useful.  To use it, 'dpkg --set-selections < /tmp/installed &&
apt-get dselect-upgrade'.

: Thanks in advance for any help

Good luck.  Not all Ubuntu packages have the same names as their Debian
counterparts, so you may have some issues doing a straight import like
that.  IMLE it tends to mostly work, however.


Dickon Hood
-- 
Due to unending piles of junk mail, my .sig is temporarily unavailable.
Normal service will be resumed as soon as possible.  We apologise for the
inconvenience in the meantime.

This email was sent from a colocated server, and needs no excuses.