Questions pertaining to APT HOWTO

michapma · 10-01-2004, 03:01 PM

Occasionaly when I am reading the APT How-To I run across things that I don't understand. Usually this should require little feedback from the more experienced members, but it is of great help to me and other readers. Hopefully we can clear some things up; I might bump this thread with questions from time to time.

A first question refers to terminology. There are references to Debian versions, and references to distributions. Then there are branches. One crosses these repeatedly. For example, in section 3.8: "People are sometimes interested in using one of the Debian versions as its main system distribution and one or more packages from another branch."

Is it correct that the versions are the "releases," i.e., Potato, Slinky, Woody, Sarge or even the permanent Sid?

Now in normal Linux terminology, distributions are Debian, SUSE, Redhat, Gentoo, etc. Here it is clear that a different sense is meant, but unclear what that is.

I don't know, so: What is a branch?

As you might imagine, I got the idea for this thread while puzzling over a given context. That context is naturally the same as the above citation, section 3.8, about the mixed system. There it refers to the file:
/etc/apt/apt.conf

I don't have this file on my system. Here's what I do have:

Code:

nathan:/etc/apt# ls -la
total 8
drwxr-xr-x   3 root root 1024 2004-09-29 23:40 .
drwxr-xr-x  84 root root 4096 2004-10-01 22:56 ..
drwxr-xr-x   2 root root 1024 2004-09-26 23:39 apt.conf.d
-rw-r--r--   1 root root  230 2004-09-29 23:40 sources.list
-rw-r--r--   1 root root  182 2004-09-25 03:20 sources.list~
nathan:/etc/apt# cd apt.conf.d/
nathan:/etc/apt/apt.conf.d# ls -la
total 4
drwxr-xr-x  2 root root 1024 2004-09-26 23:39 .
drwxr-xr-x  3 root root 1024 2004-09-29 23:40 ..
-rw-r--r--  1 root root  182 2004-09-14 05:17 70debconf
-rw-r--r--  1 root root  221 2004-08-20 15:42 99-localepurge

Can I simply create an apt.conf and things will go fine?

This will help me run the occasional package from Sid.

macondo · 10-01-2004, 04:21 PM

"People are sometimes interested in using one of the Debian versions as its main system distribution and one or more packages from another branch."

Let's say i use Sarge as my main system, but want to use a package from Sid.

"There it refers to the file:
/etc/apt/apt.conf

I don't have this file on my system. Here's what I do have:
[...]"

sure.

HappyTux · 10-01-2004, 05:35 PM

Quote:

Originally posted by michapma
[B]Occasionaly when I am reading the APT How-To I run across things that I don't understand. Usually this should require little feedback from the more experienced members, but it is of great help to me and other readers. Hopefully we can clear some things up; I might bump this thread with questions from time to time.

A first question refers to terminology. There are references to Debian versions, and references to distributions. Then there are branches. One crosses these repeatedly. For example, in section 3.8: "People are sometimes interested in using one of the Debian versions as its main system distribution and one or more packages from another branch."

Is it correct that the versions are the "releases," i.e., Potato, Slinky, Woody, Sarge or even the permanent Sid?

Well the first three would be releases Sarge has yet to be released and SID never will be, these I think would be the branches that are mentioned it gets a little confusing because they use the terms sometimes to mean the same thing in the docs.

Quote:

Now in normal Linux terminology, distributions are Debian, SUSE, Redhat, Gentoo, etc. Here it is clear that a different sense is meant, but unclear what that is.

I believe this would be in reference too Potato, Slink, Woody having been released and distributed.

Quote:

I don't know, so: What is a branch?

This I am pretty sure means the different versions you can be running being referred to as a branch eg. you run the woody, sarge or sid branches but it is a little confusing, this is how I usually refer to them as though.

Quote:

As you might imagine, I got the idea for this thread while puzzling over a given context. That context is naturally the same as the above citation, section 3.8, about the mixed system. There it refers to the file:
/etc/apt/apt.conf

I don't have this file on my system. Here's what I do have:

Code:

nathan:/etc/apt# ls -la
total 8
drwxr-xr-x   3 root root 1024 2004-09-29 23:40 .
drwxr-xr-x  84 root root 4096 2004-10-01 22:56 ..
drwxr-xr-x   2 root root 1024 2004-09-26 23:39 apt.conf.d
-rw-r--r--   1 root root  230 2004-09-29 23:40 sources.list
-rw-r--r--   1 root root  182 2004-09-25 03:20 sources.list~
nathan:/etc/apt# cd apt.conf.d/
nathan:/etc/apt/apt.conf.d# ls -la
total 4
drwxr-xr-x  2 root root 1024 2004-09-26 23:39 .
drwxr-xr-x  3 root root 1024 2004-09-29 23:40 ..
-rw-r--r--  1 root root  182 2004-09-14 05:17 70debconf
-rw-r--r--  1 root root  221 2004-08-20 15:42 99-localepurge

Can I simply create an apt.conf and things will go fine?

Now this I am positive on you simply create the file and it is used by the system and at the same time you would most likely want an /etc/apt/preferences file as well to tell the system where you want the packages coming from with the highest priority branch/package(s) (you can use either in an and/or use eg. both at the same time in the file or only one method at a time) being the one chosen by the system for install.

Quote:

This will help me run the occasional package from Sid.

This is apt pinning and what the preferences file is used for.

michapma · 10-02-2004, 06:22 AM

HappyTux,
Thanks very much on the confirmation on apt.conf and preferences. I'll apply it as per your advice in my current sound thread.

I'm still not clear on the terms version, distribution and branch, but your response does help me see that there is some equivalence in the way they are used in this instance. They all seem to be referring more or less to the same kind of thing. I'll keep my eyes out as I read the docs and see if I can work it out more specifically. That particular sentence did throw me though.

macondo · 10-02-2004, 07:51 AM

Outside Debian, 'distributions' are suse, mandrake, gentoo, etc.

within Debian:

branches = distributions = versions
(sid, sarge, woody)

capisci, amico?

why would they talk about suse, when explaining apt-pinning?

Don't look for a fifth leg on a cat, don't miss the forest for the trees.

michapma · 10-02-2004, 08:07 AM

"Now in normal Linux terminology, distributions are Debian, SUSE, Redhat, Gentoo, etc. Here it is clear that a different sense is meant, but unclear what that is."

Don't know what kept me from seeing this earlier, but it is easy to gather from the text what a version is:

Quote:

APT::Default-Release "version";

Where version is the version of Debian you want to use as the main distribution. The versions you can use are stable, testing and unstable.

Then, they use an equivalence between version and distribution, but then throw in the very confusing "version of the distribution."

Quote:

...the `unstable' version of Debian is the version to which the newest versions of Debian packages are uploaded first. This distribution sees all of the changes that packages go through, both small ones and more drastic ones which affect many packages or the whole system. For this reason, this version of the distribution should not be used by inexperienced users or by those who need proven stability.

In my opinion it would be much clearer to avoid using version as a term and stick to something like branch or distribution.

So I more or less agree with branch = distribution = version, but I believe they refer to stable, testing and unstable, rather than Woody, Potato, etc. Weird to use three terms for the same thing and then say "version of the version.

Edit: disabled smilies

HappyTux · 10-02-2004, 08:26 AM

Quote:

Originally posted by michapma

Then, they use an equivalence between version and distribution, but then throw in the very confusing "version of the distribution."

That refers too in the case of Woody for instance version of the released distribution eg. 3.0r1, 3.0r2 and now 3.0r3 is in the planning stages I just seen a mail this morning for it, damn confusing indeed.