distro installs

[Ralf Mardorf]

On Sat, 2011-11-19 at 07:40 -0800, Len Ovens wrote:
> On Fri, November 18, 2011 11:36 pm, Ralf Mardorf wrote:
> > On Fri, 2011-11-18 at 22:14 -0800, Len Ovens wrote:
> >> Can a dummy package be made that makes it look like they are
> >> installed? There must be a proper way of doing this.
> >
> > # equivs-control <package name>
> > # gedit <package name>
> > # equivs-build <package name>
> > # dpkg -i <package name...deb>
> >
> > http://www.debian.org/doc/manuals/apt-howto/ch-helpers.en.html
> 
> So, from looking at the docs at the link, it would seem that the two extra
> packages need to have their "provides" lines checked to make sure it
> satisfies anything the normal packages provide and then just not ship or
> select the normal packages.
> 
> That sounds too simple to be true ;-)  Next question becomes are the
> "normal" packages separate? or are they included as part of another
> package we also need? Is there a way of not installing a part of a
> package? Or is it easier to just do a second install process that forces a
> writeover. I have had an install that wants to remove not only the depend,
> but everything that depends on it including software I want to use.
> Synaptic is pretty smart.....
> 
> Anyway, it would be best not to have to maintain a US specific package
> that is the same as another package just to change two files...
> 
> Len

I'm using a lot of dummy packages. Sometimes I care about dependencies
and versions, in other words, I add that a package depends to another
package version >= x etc. to the dummy, but most of the times I simply
use the names of the packages that should be replaced by the dummies and
don't add anything. In cases when I don't know what I do, I backup the
Linux before I add a dummy package.
It's simple. Backup your Linux, build and add the dummies. Usually
nothing bad happens.
I'm using this e.g. when I add Jack2 from svn. For my Debian I need to
add latest ALSA before it was packaged, since I bought a RME PCIe card,
somebody showed me the way to build real Debian packages. Building real
packages seldom isn't worth the effort. If I ever should do this again I
need to search and read the notes how to do this, for me it's
complicated, I've forgotten how to do this.
In some cases there's a way to automatically build Debian packages when
you compile something. You only need to run a simple Debian command or
checkinstall instead of make install. I prefer checkinstall, since this
can be used for .deb and .rpm, but while the Debian way includes
dependencies, checkinstall doesn't. Anyway, you just want to fake that
there are packages installed, that aren't installed. I e.g. did this
when Debian testing upgraded from GNOME 2 to GNOME 3, since this upgrade
tried to force me to install Pulseaudio. I faked that there is
Pulseaudio and another thingy is installed by 2 dummy packages and
nothing bad happened, at least not for my needs.

It's that easy. Not installing a dummy package for stuff that you anyway
don't need, might force you to remove needed packages or to abandon some
new packages that you need.

Backup your Ubuntu and then test what happens if you add the dummies.

>From another Linux or a live CD run tar.

If you need to backup your Ubuntu often you might want to do it by a
script.

>From a Suse install I backup my Debian very often using this script:

#!/bin/sh
# sh ./backup_debian

BACKUP_NAME_ADD="Nov-18-2011-snapshot"

clear
echo "We are going to backup Debian"
echo "Ensure that /media/debian and /media/music2 are mounted."
echo "Press enter to continue."
read any_pushed_key

cd /media/debian
clear
echo "Debian backup starting now."
tar czf /media/music2/debian_$BACKUP_NAME_ADD.tar.gz *
 
clear
cd /media/music2
ls debian_*.tar.gz -hAl

exit 0

Note that regarding to globbing the * won't add hidden files for the
root directory, but for any sub-directory the hidden files are included.

I suspect you're aware how to backup a Linux, so pardon ;).

Just give he dummy packages a try.

Regards,

Ralf