HAL: what does it do?

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heavytull

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Jul 16, 2007, 10:23:30 AM7/16/07
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I tried to use HAL under slack 12;
it is enabled by default, so i just had to add myself as a common user
to the groups cdrom and plugdev; and now?? what should i get??
In the slack 12 annoucement by the author P.V. it is written:
" We have added to Slackware support for HAL (the
Hardware Abstraction Layer) which allows the system administrator to
add
users to the cdrom and plugdev groups."
and restarted the deamon


So i though that HAL was designed to help me adding users to cdrom and
plugdev groups which was quite surprising because usermod do that very
well. so I guessed I didn't really understand the sentence or it was
badly written.

the following was telling more:
"Then they will be able to use items
such as USB flash sticks, USB cameras that appear like USB storage,
portable hard drives, CD and DVD media, MP3 players, and more, all
without
requiring sudo, the mount or umount command. Just plug and play. "

so i finally thought that removable devices would appear in the fs
explorer automaticall.as i plug them in, none of it happened.

i think that's not normal

Thomas Overgaard

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Jul 16, 2007, 11:46:30 AM7/16/07
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heav...@hotmail.com wrote :

> I tried to use HAL under slack 12;
> it is enabled by default, so i just had to add myself as a common user
> to the groups cdrom and plugdev; and now?? what should i get??

I'm using KDE as my dm and I had to add an entry for the cdrom in
/etc/fstab to get it going. Its a bit strange that this line has been
left out in Slackware 12 but it has.
--
Thomas O.

This area is designed to become quite warm during normal operation.

notbob

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Jul 16, 2007, 1:10:18 PM7/16/07
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On 2007-07-16, Thomas Overgaard <tho...@post2.tele.dk> wrote:

> I'm using KDE as my dm and I had to add an entry for the cdrom in
> /etc/fstab to get it going. Its a bit strange that this line has been
> left out in Slackware 12 but it has.

It was in MY 12 fstab file. Did you install from a cdrom?

nb

motion musso: aka sathia

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Jul 16, 2007, 1:41:03 PM7/16/07
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heavytull wrote:

> I tried to use HAL under slack 12;
> it is enabled by default, so i just had to add myself as a common user
> to the groups cdrom and plugdev; and now?? what should i get??
> In the slack 12 annoucement by the author P.V. it is written:
> " We have added to Slackware support for HAL (the
> Hardware Abstraction Layer) which allows the system administrator to
> add
> users to the cdrom and plugdev groups."
> and restarted the deamon

open a Kde window and type:

system:/media

--
777 fanno 21, arriva la volante e non c'è nessuno

Thomas Overgaard

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Jul 16, 2007, 4:28:40 PM7/16/07
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not...@nothome.com wrote :

> It was in MY 12 fstab file. Did you install from a cdrom?

No I did my install from a homemade 8cm. DVD+RW. But the line that made
the difference looks like this:
/dev/cdrom /mnt/cdrom auto noauto,user,ro 0 0

Dan C

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Jul 16, 2007, 9:52:45 PM7/16/07
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On Mon, 16 Jul 2007 12:10:18 -0500, notbob wrote:

>> I'm using KDE as my dm and I had to add an entry for the cdrom in
>> /etc/fstab to get it going. Its a bit strange that this line has been
>> left out in Slackware 12 but it has.

> It was in MY 12 fstab file. Did you install from a cdrom?

I installed from a CD, and my cdrom entry in /etc/fstab was commented out
(with a #). Automounting of CD's wasn't working, so I uncommented it and
it did work. I'm using Xfce. Not sure why/how it got commented, but
things are working well now...


--
"Ubuntu" -- an African word, meaning "Slackware is too hard for me".

King Beowulf

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Jul 17, 2007, 12:05:55 PM7/17/07
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A previous post from Robby Workman explains the issue. In short, you must MANUALLY
add your users, including root, to the appropriate groups in /etc/group

floppy
audio
video
cdrom
plugdev

and comment out cdrom entry (and floppy if you still use them) in /etc/fstab
(essentially only hdx, proc

then reboot. In XFCE, a cdrom icon pops up that you can open to view. In KDE a
window pops up (is so configured) unless you manually configured KDE to show drives
in the desktop.

So far it works fine here for CDROMs and USB sticks.

The whole idea behind HAL/dbus/plugdev is to provide for Linux distributions the same
automatic hardware detection and drive mounting as in MS Windows and Apple OS X.

Peter Chant

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Jul 17, 2007, 2:55:36 PM7/17/07
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heavytull wrote:

> I tried to use HAL under slack 12;

What worries me is that my web cam now has an orange glow and I can only
shut the system down by unplugging the RAM whilst it sings daisy...

:-)
--
http://www.petezilla.co.uk

King Beowulf

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Jul 17, 2007, 3:33:34 PM7/17/07
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Peter Chant wrote:
> heavytull wrote:
>
>> I tried to use HAL under slack 12;
>
> What worries me is that my web cam now has an orange glow and I can only
> shut the system down by unplugging the RAM whilst it sings daisy...
>
> :-)

Well, as long as the pod bay doors open when you need to get in....

heavytull

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Jul 21, 2007, 9:34:36 AM7/21/07
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heavytull wrote:

On Jul 17, 6:05 pm, King Beowulf <kingbeow...@nospam.gmail.com> wrote:
> A previous post from Robby Workman explains the issue. In short, you must
MANUALLY
> add your users, including root, to the appropriate groups in /etc/group
>
> floppy
> audio
> video
> cdrom
> plugdev
>
> and comment out cdrom entry (and floppy if you still use them) in /etc/fstab
> (essentially only hdx, proc
>

ok thas what i did

> then reboot. In XFCE, a cdrom icon pops up that you can open to view. In KDE
a
> window pops up (is so configured) unless you manually configured KDE to show
drives
> in the desktop.
>
> So far it works fine here for CDROMs and USB sticks.

doesn't not work at all here;

i even remember something like this was working under slack11 before.
indeed everytime i inserted a cdrom a window was poped up in KDE. but i never
used it. at that time the cdrom line was not commented out in my fstab

>
> The whole idea behindHAL/dbus/plugdev is to provide for Linux distributions


the same
> automatic hardware detection and drive mounting as in MS Windows and Apple OS
X.


--
heavytull

Peter Christy

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Jul 22, 2007, 4:02:18 AM7/22/07
to
If its any consolation, I'm having a very similar problem - see the post
further down "HAL question".

In my case, I have two machines on which Hal works perfectly, and a third on
which it doesn't. Yes, I've commented out the fstab line, and added my users
to the appropriate group.

The only thing I have discovered is that my case seems to be kernel related. It
works if I use the original Slack huge26.s kernel, but not my home compiled
one. (The two working machines are also running home compiled kernels)

I cannot see for the life of me what I've left out, but there must be some
option I've missed when compiling!

--
Pete
chr...@NOattglobalSPAM.net
(make the obvious amendments to reply!)

Joost Kremers

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Jul 22, 2007, 4:59:16 AM7/22/07
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Peter Christy wrote:
> The only thing I have discovered is that my case seems to be kernel related. It
> works if I use the original Slack huge26.s kernel, but not my home compiled
> one. (The two working machines are also running home compiled kernels)

so, runn a diff on the two configs, that should identify the culprit.


--
Joost Kremers joostk...@yahoo.com
Selbst in die Unterwelt dringt durch Spalten Licht
EN:SiS(9)

Peter Christy

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Jul 22, 2007, 5:46:34 AM7/22/07
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Joost Kremers wrote:

> Peter Christy wrote:
>> The only thing I have discovered is that my case seems to be kernel related.
>> It works if I use the original Slack huge26.s kernel, but not my home
>> compiled one. (The two working machines are also running home compiled
>> kernels)
>
> so, runn a diff on the two configs, that should identify the culprit.
>
>

Yes, that's a good idea - but its not going to be quite that simple! The
non-working one is running an Athlon-XP on a Via chipset, one working one is
running an Athlon-XP on an NVidia chipset, and the third is running Slamd64 on
a Via chipset! There will be a lot of differences!

Still, I think you're right, I'm just going to have to slog through it!

I'm working all over the week-end - I'll give it a try tomorrow!

Joost Kremers

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Jul 22, 2007, 6:13:22 AM7/22/07
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Peter Christy wrote:
> Joost Kremers wrote:
>
>> Peter Christy wrote:
>>> The only thing I have discovered is that my case seems to be kernel related.
>>> It works if I use the original Slack huge26.s kernel, but not my home
>>> compiled one. (The two working machines are also running home compiled
>>> kernels)
>>
>> so, runn a diff on the two configs, that should identify the culprit.
>
> Yes, that's a good idea - but its not going to be quite that simple! The
> non-working one is running an Athlon-XP on a Via chipset, one working one is
> running an Athlon-XP on an NVidia chipset, and the third is running Slamd64 on
> a Via chipset! There will be a lot of differences!

actually, i meant a diff between the huge26.s kernel and your home-grown
one. i don't know how large the differences there are, they may be large as
well...

Peter Christy

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Jul 22, 2007, 6:35:26 AM7/22/07
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Joost Kremers wrote:

> actually, i meant a diff between the huge26.s kernel and your home-grown
> one. i don't know how large the differences there are, they may be large as
> well...

Yes, I think they will be even greater... 8-(

I've diff'd my home grown configs, and at very quick look before I dash off to
work, I still can't see anything obvious. I'll have a more detailed look
tomorrow.......!

Phil

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Jul 22, 2007, 9:07:41 AM7/22/07
to
Peter Christy wrote:
> If its any consolation, I'm having a very similar problem - see the post
> further down "HAL question".
>
> In my case, I have two machines on which Hal works perfectly, and a third on
> which it doesn't. Yes, I've commented out the fstab line, and added my users
> to the appropriate group.
>
> The only thing I have discovered is that my case seems to be kernel related. It
> works if I use the original Slack huge26.s kernel, but not my home compiled
> one. (The two working machines are also running home compiled kernels)
>
AHA!! I too have similar problems. Hal works perfectly with the huge26.s
kernel that comes with slackware 12, but I have no sound because the
sound drivers for my soundchip are broken in the 2.6.21 kernel. I
downloaded 2.6.22 from kernel.org, recompiled, and now sound works but
hal doesn't. I copied the original .config file to my 2.6.22 directory
and did make oldconfig to no avail.

> I cannot see for the life of me what I've left out, but there must be some
> option I've missed when compiling!
>

My thoughts exactly.

Also I have another problem, when I try to play a DVD with xine as a
normal user, I get a NAV error. If I leave the DVD in the tray, logout,
then log back in, then it plays ok. Have no problems playing DVDs as
root. I have a sneaking suspicion that this is the same problem as we've
been discussing above.

Regards
Phil

Peter Christy

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Jul 23, 2007, 12:59:23 PM7/23/07
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Phil wrote:

> AHA!! I too have similar problems. Hal works perfectly with the huge26.s
> kernel that comes with slackware 12, but I have no sound because the
> sound drivers for my soundchip are broken in the 2.6.21 kernel. I
> downloaded 2.6.22 from kernel.org, recompiled, and now sound works but
> hal doesn't. I copied the original .config file to my 2.6.22 directory
> and did make oldconfig to no avail.

Ok, I've proved to my satisfaction that its a kernel config problem - at least
in my case!

I built a new kernel (2.6.22) using the huge26.s config file, and taking all
the default options on "make oldconfig". Automounting worked!

I then rebuilt the kernel using config options suitable for my machine (it
built an awful lot quicker!) and now automount doesn't work!

Either I've built something as a module that needs to be in the kernel (or
modprobe'd on boot) or I've missed something out.

It isn't device-mapper or autofs.

Diff'ing huge26.s and my configs produced a huge file! It's like looking for a
needle in a haystack!

Any suggestions anyone?

Joost Kremers

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Jul 23, 2007, 2:05:14 PM7/23/07
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Peter Christy wrote:
> Ok, I've proved to my satisfaction that its a kernel config problem - at least
> in my case!
>
> I built a new kernel (2.6.22) using the huge26.s config file, and taking all
> the default options on "make oldconfig". Automounting worked!
>
> I then rebuilt the kernel using config options suitable for my machine (it
> built an awful lot quicker!) and now automount doesn't work!
[...]
> Any suggestions anyone?

well, the first thing i would do is search google, and see if HAL and/or
dbus (and other stuff automounting depends on, such as udev) depend on
certain kernel functionality that you've left out. you can also check the
documentation of HAL and dbus for that.

then, if that doesn't turn anything up, check the kernel documentation
itself. a command like:

find . -name Kconfig | xargs grep -C 2 HAL

executed in the top directory of the kernel source tree will give you all
occurrences of 'HAL' in the kernel help files with two lines of context
before and after. do the same for dbus (you may want to add -i to make the
search case insensitive). perhaps some mention is made of kernel modules
that are required for either or both.

if you then still haven't found anything, the only other method is to go
from the huge26.s kernel to your own config in steps, and see which step
breaks automounting. start out with the huge26.s config, take out
everything you're pretty sure has nothing to do with it, compile and
boot. if automounting still works, take out the next batch. lather, rinse
and repeat until the culprit is identified.

HTH

Jerry Peters

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Jul 23, 2007, 4:32:29 PM7/23/07
to

There have been some changes in the structure of sysfs recently that
possibly could break HAL, so take a look at the config options dealing
with sysfs. Look at any differences in options with names that include
the string COMPAT or DEPRECATE. Or try searching the kernel mailing
list archives for threads containing "sysfs broke".

Jerry

Phil

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Jul 24, 2007, 7:13:53 AM7/24/07
to
In my case, I think it was operator error. I started again from scratch,
reinstalled kernel 2.6.21.5 source files, then copied the .config file
to my 2.6.22 directory. Did a make oldconfig. Kernel recompiled
successfully and hal was working ok. Removed all the stuff I don't need
with make menuconfig and recompiled once more and again hal was working.
First time round I must have set/unset something inadvertently. My
apologies for troubling you. Thanks everybody for your input
Regards
Phil

Peter Christy

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Jul 28, 2007, 9:15:05 AM7/28/07
to
FOUND IT! (At last!!!)

You need to have INOTIFY selected under "filesystems"....!

Doh!

8-)

Phil

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Jul 29, 2007, 6:44:36 AM7/29/07
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Peter Christy wrote:
> FOUND IT! (At last!!!)
>
> You need to have INOTIFY selected under "filesystems"....!
>
> Doh!
>
> 8-)
>
Give that man a biscuit :^)
I'd made so many changes to my config, I didn't have a clue which one
was wrong, though I thought it maybe somewhere in the filesytem.
Regards
Phil
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