How to obtain list of installed packages

[Bret Busby]

On 20/05/2016, Petter Adsen <petter at synth.no> wrote:
> On Fri, 20 May 2016 11:53:15 +0800
> Bret Busby <bret.busby at gmail.com> wrote:
>
>> Hello.
>>
>> Thank you for the advice.
>>
>> However, whilst it is a while ( a few weeks or so), since I last saw
>> the error message about the problems with the partitioning, and, I do
>> not know how to get the error message again, to be able to write it
>> down, word for word, to explicitly and accurately reproduce the exact
>> message, from memory, it is something along the lines of "Your hard
>> drive partitioning is stuffed - the partition sizes and (/or) the
>> start and end points of the partitions do not match the partition
>> table", and, from memory, it involved the equivalent (as it no longer
>> exists, with the GPT, rather than a FAT, or so I understand) of an
>> extended partition, where, if this was an older FAT system, and I had
>> created an extended partition in which to set up the partitions to
>> install the various operating systems other than the pre-installed
>> Windows, the whole of the extended partition would need to be deleted
>> and created again, so that the start and end points of the extended
>> partition, and each of the logical partitions within it, could be
>> (reasonably) ensured to be correctly placed.
>
> Bret, many of the readers on this list do not speak English as their
> first language. I could not make sense of the above myself, do you
> think you could split your sentences up a bit and use a period now and
> then? It would massively improve readability.
>
> BTW, the newer system is called GPT as you say, the older is MBR. FAT
> is a family of file systems. GPT does not have logical and extended
> partitions.
>
>> The error that I got, is something that I had not previously
>> encountered; either the error itself, or, the type of error, which, to
>> me, with my (relative) lack of knowledge in this area, is the
>> equivalent of the error message stating that a File Allocation Table
>> is wrong/stuffed/needing replacement.
>
> If a FAT is borked, that would indicate a problem with a file system,
> not partitions. Do you have any FAT file systems on the disk?
>

When I went to install operating systems other than MS Windows 8 on
the system, I shrunk the Windows partition as much as possible, and
then created new partitions, and, I have since, resized some of those
partitions, after I found that no need exists, to have a partition of
around 100GB, for an operating system, in addition to having a 100GB
partition applicable to each operating system.

So, whilst it is not a case of a FAT with physical primary partitions
and logical partitions within an extended partition, the HDD has the
partitions that existed when the system was purchased (about four or
five, I believe), except that the Windows partition was shrunk as much
as possible, and, then, the partitions that I created and then further
manipulated.

In the process, something has apparently gone wrong with the table
that manages the partitions (the GPT?), and the start point and end
point locators and/or the partitions sizes records.

If I knew how to reproduce the particular error message, it would
probably be quite helpful, in all of this, as I may be completely
wrong, in my perception of the need to rebuild the file systems on the
HDD.

>> Thus, I was intending to, or, investigating/considering repartitioning
>> the whole of the HDD, as much as possible (including eliminating the
>> infidel MS Windows 8, which I could never use without great anguish,
>> and, for which, I have forgotten the passwords), and, creating a new
>> system of partitions, with a single installed operating system (which,
>> at this stage, would be reinstalled UnbuntuMATE 15.10, as I have seen
>> on the list, many reports of problems with Ubuntu 16.04), which I
>> know, has drivers for all of the hardware of the computer, and, which
>> is the only operating system (other than MS Windows 8, and possibly
>> later versions) that I know to have all of the drivers for the
>> hardware and thence, be (relatively) fully functional on the computer.
>
> Ubuntu 15.10 is going EOL in a couple of months, at some point you
> might want to consider testing a 16.04 LiveCD to see if it works
> properly. If it does, you probably want to upgrade before support for
> 15.10 ends so you will continue to get security fixes.
>
> You are correct that there have been problems with 16.04, although it
> works fine on my machines. It depends on what software you rely on, and
> bugs are being fixed every day. By the time 15.10 goes EOL xenial will
> probably have improved a lot.
>

What I was intending to do, was to stay with 15.10, until the
publicised problems with 16.04, had been resolved/disappeared.

I had understood that the support for non-LTS versions of Ubuntu, was
about 18 months. I must be wrong, in that understanding

>> Since posting my original query, in this thread, it has occurred to
>> me, that, when I have the available time, the simplest way to achieve
>> what I want, regarding the list of packages, is to work through the
>> Applications menu, and write down every application name for each
>> category of applications, and then, to ensure that each of those
>> applications listed, is installed in the new build.
>
> No, the simplest way is, as I previously posted, to use apt-clone. It
> needs to be installed first. apt-clone will take a snapshot of all
> installed packages, any repositories you may have added, and all keys
> for apt. This snapshot can later be restored onto the same or another
> computer. If you use the --with-dpkg-repack option it will also make
> copies of any packages you have installed locally and put them in the
> archive as well.
>
> 'apt-clone clone --with-dpkg-repack packages' will create a compressed
> tarball called 'packages.tar.gz'. On the machine you want to restore it
> you run 'apt-clone restore packages.tar.gz'.
>
>> >From the responses that I have seen posted on the list, so far, I
>> >am
>> not aware of a simpler or more efficient method of obtaining a list of
>> the packages that I need to install, in addition to the base system
>> packages, in order to replicate, as much as possible, the
>> functionality of the existing system.
>
> Try the above. Also remember to copy any configuration files you would
> like to save from your home directory (and /etc). Configuring everything
> from scratch can easily take a lot more time than re-installing
> packages.
>
> Petter
>

Okay; I intend then, to try that, when I can.

-- 

Bret Busby
Armadale
West Australia

..............

"So once you do know what the question actually is,
 you'll know what the answer means."
- Deep Thought,
 Chapter 28 of Book 1 of
 "The Hitchhiker's Guide to the Galaxy:
 A Trilogy In Four Parts",
 written by Douglas Adams,
 published by Pan Books, 1992

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