Backing up your package list WAS screen resolution problems with Hardy Herron

[Owen Townend]

2008/9/28 Derek Broughton <news at pointerstop.ca>:
> Owen Townend wrote:
>
>> 2008/9/27 NoOp <glgxg at sbcglobal.net>:
>>>
>>> Here's a challenge for you: reformat your existing hardrive(s) and
>>> install your Windows from scratch. Then install your other standard
>>> applications (office, graphics, graphics editing programs, scanning
>>> programs, pdf reader programs, music players, video player, internet
>>> software, IMS sofware, calendar programs, etc.) on that fresh Windows
>>> install. Let us know how you come out; how long it took you, what worked
>>> 'out-of-the-box' and what did not, etc.
>>>  Then, and only then, install Ubuntu on a second hard drive or
>>> partition, and come back and tell us about your experience.
>>>
>>
>> Hey,
>> Further to that... try something as simple as this to duplicate or
>> backup your current set of apps:
>> dpkg --get-selections > installed_apps.txt
>> dpkg --set-selections < installed_apps.txt
>
> Well, actually, no.  That's a truly ugly way to install software, and I
> heartily recommend NOBODY follow that advice.  You'll never get rid of all
> the cruft in future (every single package on the system is now marked
> as "manually installed" and will not be removed if nothing needs it in
> future).
>
[snip]
> --
> derek

yeah, it was only an example of the possibilities with a single
overarching package manager...
I agree that NOBODY should actually use that particular method and it
was not intended as advice, only as a possibility.

Something more like this would probably be closer to useable:
$ aptitude search '!(!~i|~M)' -F %p > ${aptlist}
(Search for the inverse of anything not installed or installed automatically)

What other ways do people use for this type of task?
Either backing up,restoring or duplicating system setups without doing
whole-disk backups.

cheers,
Owen.