Subject: debian version ID

From: Jonathan de Boyne Pollard <[email-masked]>
Date: Mon, 29 Aug 2016 12:27:31 +0100

Felix Miata:

> Will someone please explain (or point to, since it's not in release 
> notes), why:
> 1: /etc/os-release (in Jessie at least) does not include the point 
> release version as represented by /etc/debian_version

Andrew M.A. Cater:

> /etc/os-release just contains major version - the absolute need for 
> minor version is small.

Jonathan de Boyne Pollard:

> You are going to have to explain that to its manual page, which gives 
> VERSION_ID=11.04 as an example of what can be in the file.

Pascal Hambourg:

> This is obviously not a Debian version. Rather looks like Ubuntu.

That is irrelevant.  M. Miata asked for a reason.  M. Cater responded.  
Either M. Cater is responding to explain why or xe is not explainining 
but merely repeating what M. Miata already knows and wants to know the 
reason for.  As an explanation why, it is clearly wrong, from simply 
reading the user manual.  What the version number in the manual might be 
is simply irrelevant.

---

From: "Andrew M.A. Cater" <[email-masked]>
Date: Mon, 29 Aug 2016 18:27:39 +0000

On Mon, Aug 29, 2016 at 12:27:31PM +0100, Jonathan de Boyne Pollard wrote:
> >1: /etc/os-release (in Jessie at least) does not include the point release
> >version as represented by /etc/debian_version
> 
> Andrew M.A. Cater:
> 
> >/etc/os-release just contains major version - the absolute need for minor
> >version is small.
> 
> Either M. Cater is responding to explain why or xe is not explainining but
> merely repeating what M. Miata already knows and wants to know the reason
> for.  As an explanation why, it is clearly wrong, from simply reading the
> user manual.  What the version number in the manual might be is simply
> irrelevant.

What part of the man pages are you finding hard to read: it's worth noting that much of this is optional

The below is the version from Debian Jessie [/etc/os-release is a symlink to/from /usr/lib/os-release]

PRETTY_NAME="Debian GNU/Linux 8 (jessie)"
NAME="Debian GNU/Linux"
VERSION_ID="8"
VERSION="8 (jessie)"
ID=debian
HOME_URL="http://www.debian.org/"
SUPPORT_URL="http://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"

PRETTY_NAME is a name in a format suitable for presentation to the user. May (or may not) contain a release name or OS version of some kind. If it's not set,
the default is Linux.
NAME identifies the operating system without a version component
VERSION_ID  is a lower case string, mostly numeric identifyng the OS version for use by scripts. Optional. 
[The examples given in the manpage are for Fedora and Ubuntu releases. NOTE: These are examples and are not canonical since the whole field is optional.]
VERSION identifies the OS version, possibly including a code name
ID is a lower case identifier identifying the OS suitable for use in scripts
HOME_URL, SUPPORT_URL and BUG_REPORT_URL are all optional: intended for distributions providing community support and not all of these need be given.

I correctly pointed out that minor versions point releases have been of less relevance since prior to Debian 7 and the last time I can think of them as being very 
relevant indeed was prior to Debian 4.0

Debian isn't Ubuntu (or Red Hat Enterprise / CentOS / Fedora / OpenSUSE) ...

Please don't impute motive to me: please do go away and read and learn as much as you feel able to do before complaining about inconsistencies which aren't.
I would sinerely commend to you the Debian handbook - apt install debian-handbook will get you the PDF version: it is also worth springing for a paper version
to keep at the computer side. [Also, obviously, at https://www.debian.org/doc/user-manuals/#debian-handbook in HTML.]

Alternatively, others less charitable might recommend Eric Raymond's classic: How To Ask Questions The Smart Way www.catb.org/esr/faqs/smart-questions.html

With every good wish,

Andy C (Debian user since 1994 and Debian developer since 1995)

[[email-masked]]

---

From: "Andrew M.A. Cater" <[email-masked]>
Date: Mon, 29 Aug 2016 19:45:21 +0000

> Andy C (Debian user since 1994 and Debian developer since 1995)

Following up to myself (since I hadn't really bothered previously with /etc/debian_version which has, roughly, the same function as /etc/release on Red Hat) and thereby 
accidentally answering the original question asked by ?? Felix ?? Miata:

The OS portable version of OS identification is /usr/lib/os-release or /etc/os-release as outlined above. /etc/debian_version coincidentally adds the minor
release - it doesn't have a man page so I can't check why.

It appears that Ubuntu (mis)uses /etc/debian_version to point out the version of Debian from which Ubuntu point releases derive their basis.

Ubuntu releases typically take Debian testing at some point, spend a few months cleaning it up to their satisfaction - perhaps adding packages from 
Debian unstable (always, canonically, Sid) - and then release.

There is a mapping at http://askubuntu.com/questons/445487/which-ubuntu-version-is-equivalent-to-debian-squeeze if this will help anyone, but, as the question
answer points out there may be no feasible exact mapping.

Hope this helps someone at some tme

All the very best,

Andy C

---

From: Lisi Reisz <[email-masked]>
Date: Mon, 29 Aug 2016 23:33:38 +0100

On Monday 29 August 2016 20:45:21 Andrew M.A. Cater wrote:
> /etc/debian_version coincidentally adds the minor
> release

Whatever the reason, it is very helpful to some of us that it does so, so long 
may it continue to do so!! :-)

Thank you for the helpful explanation, Andrew.

Lisi