[techtalk] Differences between linux distributions

[Telsa Gwynne]

On Sat, Feb 19, 2000 at 09:39:20PM -0500 or thereabouts, Tania M. Morell wrote:
> Hi all,
> 
> I've used Berkeley unix and SunOS for years at my university but not
> linux. I use Mandrake at work and RedHat intermittently at home but I've
> yet to understand the differences between them..  Maybe I haven't used
> them long enough to figure it out, or maybe I'm stupid.
> 
> What are the main differences between distributions of linux like
> RedHat, Mandrake, Debian, Caldera...  etc.  Can anyone tell me?

Laurel was collecting experiences of installing and running different
distributions, wasn't she? Did anything come of that? 

I originally had a long long ramble on the differences I knew between
the distributions, but my husband wandered past and insisted (from
his kernel-biased view) that "really, there's not _that_ much
difference" when I asked. He further explicated,

  "The kernel is very SysV. Except for the networking which is very
BSD. The C library does both, and userland tends to favour BSD in
its arguments (ie ps aux instead of ps -edalf) but its mostly GNU
tools instead of BSD tools. The filesystem layout _tends_ to favour
SysV in its init scripts but the directory layout is more BSD."

I hope that makes it all clear :) Since you originally mentioned
knowing SunOS and BSD, it might help!

I think it helps if you know what "SysV" and "BSD" styles _are_.
I don't, really :)

Long stuff follows. Corrections very welcome. I know very little
about Caldera, and my last experience of running SuSE was when the
manual was in German, which is also about the period we stopped
having Slackware at home. I may be dated :)

There is a proposed Filesystem Hierarchy Standard for Linux, which
you can read at http://www.pathname.com/fhs/ (make sure you're looking
at the latest version: it links to at least two!). It's a really
good read for finding out what typically goes where -- except of
course that "typical" doesn't mean "universal". I think most vendors
are involved with establishing some kind of standard, but at the
momemt, there's various differences. Regardless of my dear one's
"they're pretty similar really". 

The classic example is KDE and GNOME. SuSE makes use of the /opt 
hierarchy for these. Red Hat puts them in /usr/share. Debian puts
GNOME in /usr. I don't know about Caldera: perhaps /opt? Does it
even ship GNOME? This causes Religious Wars. 

I don't really know what the init scripts are either. I think it's
"what's in /etc/rc.*". I do know that Slackware used to use the BSD-style, 
and I think SuSE started out based on that, and I have no idea whether 
either of them remained that way or changed :)

I _do_ know, however, that the reason you didn't see much difference 
between Red Hat and Mandrake is that Mandrake started out as "Red Hat 
for pentiums, with KDE and a graphical installer". They have both 
changed since then: Red Hat now ships KDE and a graphical installer, 
and Mandrake no longer use the pgcc compiler. But they are probably 
the two which are most similar out of the lot. 

Rough family tree (which ignores practically all the non-Intel stuff,
sorry)

Slackware
(came from SLS, one of the original distributions)
	-> SuSE (originally)
	-> Stampede?
	-> influences on practically all of the rest, too.

Jurix (long-gone)
(dunno where it came from)
	-> SuSE (originally)

Bogus (long-gone)
(dunno where it came from, borrowed lots from everywhere?)
	-> elements of the package manager in Red Hat _and_
	-> elements of the package manager in Debian, too!

Red Hat
(bits of Bogus, bits of Slackware? Dunno)
	-> original Caldera was based on RH, then diverged very fast,
	introducing graphical installers, new packages, etc.
	-> Mandrake very based on Red Hat.
		"	-> Macmillan Linux based on Mandrake
			-> LinuxOne (ahem ahem) also based on Mandrake?
	-> Definite Linux (UK one: RH+crypto)
	-> Connectiva (popular in Brazil)

Debian 
(came from Bogus, we _think_. Also, for some reason, Debian meta-distros 
only started up recently although Debian's been around for ages.)
	-> Stormix or something?
	-> Corel Linux

I have used quite a few of these due to my husband's habit of trying
practically everything out at some stage, but on most of them I was
still at the level of 'elm, nethack, yahtzee' as 90% of my bash history.

Differences that are noticeable to me:

Preferred GUI: some give you GNOME by default (Red Hat, Debian).
Others give you KDE by default (Caldera, SuSE, originally Mandrake,
dunno if it still does.)

Filesystem setups: Red Hat has an extra layer of subdirectories in 
/etc/rc.* compared with Debian. It has directories of things in
/etc where some others have a lot more files in it, not in subdirectories,
I _think_.

Package management: 
	rpm (Red Hat, Caldera, SuSE, Mandrake, Definite)
	dselect/apt-get (Debian, presumably Corel)
	I think TurboLinux may use its own?
	Slackware has something these days, I _think_ but I forget it.

How they split up (or don't) the software:
	Red Hat, Mandrake and Debian all make a conscious split between
    'free' and 'non-free' software in some way, typically putting them
    onto separate CDs (and in Debian's case, separate ftp directories?)
	Not sure what SuSE do now, but they used to include 'non-free'
    stuff mixed in: YaST (their installer) was an example, but I believe
    the licence changed? This was a pain for the local computer society,
    who used to burn CDs of anything they could for members, and ended
    up simply doing Red Hat and Debian because you couldn't just copy
    a SuSE CD without going through and checking the licence for each
    package. And no-one had time :)
	I don't want to start a religious war here. I know this matters
    very much to some people and less to others. People who are 
    attracted to the Linux world by the free software ideals might
    find that a useful one if they're looking for deciding factors.

Some of the distributions do come with particular features:
	I believe Red Hat is known for many many patches in its
    kernel. I've certainly seen people bitch about it. However, if
    it bothers you, you can unpack the kernel rpm, edit the specfile
    to ignore the patches, and re-do it :)
	SuSE used to advertise support for - erm - something - that
    not everyone did. Was it very very large files?
	Early Mandrakes used the pgcc compiler, although they now don't.
	Whether 'emacs' starts up emacs or xemacs, 'vi' starts up
    vi or vim, and so on, varies. 
	Red Hat starts sendmail as the default MTA, and I think Debian
    goes for exim.
	Corel gives you a graphical login by default, as does I _think_
    Mandrake. Some others give you a choice (Red Hat, who else?) and I
    believe some initially start at the console and leave it up to you 
    to tinker around with run levels.
	Oh yes. The run-levels can vary a bit.
	
Whoah. This is too long. Linux Magazine recently ran a comparison
between a bunch of distributions with a big pretty chart. That might
help some folks?

Telsa

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