I/uDev suck(s)

Gullible Jones · 2005-02-19 03:44:14

I have just discovered that I have been a complete idiot.

An hour ago, I tried to set up a new printer, one that would definitely work with CUPS. It didn't... Because I had no /dev/printers, no /dev/lp0, etc. :shock:

It didn't take long to realize the problem was uDev... So I set GRUB to boot with devfs and reinstalled it, and now my printer works perfectly.

I also couldn't help but notice that I now have /dev/sound, and my sound works fine... :oops:

normc · 2005-02-19 03:49:47

I don't know what your problem was, but I use idev and I had no trouble setting up my printer with cups. I have used it both directly and through a print server attached to a router. I've never had any problems with sound since I started to use ALSA.

Gullible Jones · 2005-02-19 04:08:06

Interesting. :?

Well, I'll stick with DevFS for now methinks...

phrakture · 2005-02-19 04:18:54

devfs may work fine... but it's a dead project now - the kernel devs stated "it had too many problems that were impossible to fix"

Gullible Jones · 2005-02-19 04:34:18

Be that as it may, I'll be forced to use it until uDev's bugs are ironed out.

z4ziggy · 2005-02-19 04:38:22

from the kernel:

Note that devfs has been obsoleted by udev,
<http://www.kernel.org/pub/linux/utils/kernel/hotplug/>.
It has been stripped down to a bare minimum and is only provided for
legacy installations that use its naming scheme which is
unfortunately different from the names normal Linux installations
use.

instead of escaping to a "safe side" (ie, devfs), try instead to fix your udev problem. thats the solution for the long run, since you'll have to face it sooner or later - better todo it while you have the choice...

sarah31 · 2005-02-19 05:04:36

if you are more comfortable using devfs go for it. Personally I don't think udev is anywhere near as good as devfs was and reminds me too much of how the whole kernel development has been a bit shoddy in the last year. The 2.6 kernel has not been what I expected.

I would suggest though that you keep trying now and again to get a stable udev configuration so that you are not too stuck when the time comes that the pups developing the kernel give devfs the boot.

skoal · 2005-02-19 05:14:43

I'm with gullible on this one. I tried getting udev working the other day to "bite the bullet" now and prepare myself. The NVIDIA devices and udev are like mud and water, at the present. I read many posts on how to temporarily "fix" it, but along that discovery process, I seemed to notice half the posts in these forums in the last 2 months have all been devoted to...udev.

Did the kernel maintainers take over the udev development after the creator quit maintaining it a while back? I was actually surprised when I had a hard time getting "devfs" option in kernel compile the other day. It was hidden. I thought the kernel guys at one time even thought "udev" was a dead project. Things sure did "turn on a dime" with them apparently...

tpowa · 2005-02-19 08:45:00

udev is great, we defined new rules for it that the normal user shouldn't have to care about permissions and symlinks anymore.
The user has only to add himself to the right groups, the rest is done by udev.
if problems are still there please make a bug report about it and it could be fixed. We don't have all the hardware to test so reports are always welcome, where to improve udev.
Since udev 053 it has completly changed but now it should work really great.
i'll update the udev wiki soon, hope it's clearer then.

Gullible Jones · 2005-02-21 03:38:35

You're telling me the lack of /dev/sound is part of default Arch configuration?

Now I know this sounds incredibly arrogant and stupid, but... AFAIK - and please correct me if I'm wrong, I am relatively new to *nix after all - the presence of /dev/sound isn't a matter of having things where I want them, but a matter of the functionality (or, in the case of missing /dev/sound, lack thereof) of my system's sound.

falmarian · 2005-02-21 05:59:19

/dev/sound should be completely irrelevant. it would probably just be a symlink to /dev/dsp, which would be the actual device node for your sound output.
I could be wrong here, I'm saying without checking. But I've nevr had a /dev/sound, but I listen to a lot of oggs...

Gullible Jones · 2005-02-21 17:18:52

Ah... Interesting. :? Thanks for setting me straight.

It looks like I'll just end up using a different sound card then...

alterkacker · 2005-02-21 17:43:14

GJ - The thing that might be confusing you about Unix device files in general is that it's not the name of the device file that really matters - it's what's stored in the inode. There are three pieces of information there:
- the device type: 'b' for a block device like a disk or 'c' for a character device such as a terminal or sound card
- the major number which is more or less an index into a table of device drivers; the indexed entry is the one to use for that device
- the minor number which is an instance number or other additional info.

For example, on my system:
brw-rw---- 1 root disk 3, 69 2005-02-18 10:24 /dev/hdb5
brw-rw---- 1 root disk 3, 71 2005-02-18 10:24 /dev/hdb7
brw-rw---- 1 root disk 8, 0 2005-02-18 10:24 /dev/sda
crw-rw---- 1 root tty 4, 64 2005-02-18 10:24 /dev/tts/0

The first character is the device type; the two comma separated numbers are the major & minor numbers. So the first two entries point to different partitions on an IDE disk, the third to an SATA disk (which Linux treats as a SCSI disk), and the fourth to a terminal. To see how the major number maps to different devices download the kernel source and look at file linux/Documentation/devices.txt.

Gullible Jones · 2005-02-21 18:24:21

Thanks.

Xentac · 2005-02-23 05:41:43

More likely you're "amazing" devfs experience and your "buggy" udev experience is because devfs can autoload modules, but udev doesn't. If a process tries to access a device and you're using devfs, devfs will load the module. If you're using udev, you have to load the module by hand.

Maybe with your devfs enabled, you should check your module list then try loading all those modules when you're running udev.

Gullible Jones · 2005-02-23 13:40:15

Maybe... Shouldn't be a problem with hotplug, but what the hell.

Xentac · 2005-02-23 15:23:32

/dev/sound will only exist if you have the oss compatibility modules loaded (assuming you're using alsa). Hotplug won't detect that you can load oss compatibility modules because they're not an actual card.

On the same note, the printer stuff may have been loaded by hotplug, but again, not so sure. Neither "device" ever generates events.

tarix · 2005-02-24 12:57:43

For me it worked after adding the "lp" module to the module array in rc.conf.

Gullible Jones · 2005-02-25 21:29:25

Thanks.

I am loading the OSS compatibility modules though... :?

Arch Linux

#1 2005-02-19 03:44:14

I/uDev suck(s)

#2 2005-02-19 03:49:47

Re: I/uDev suck(s)

#3 2005-02-19 04:08:06

Re: I/uDev suck(s)

#4 2005-02-19 04:18:54

Re: I/uDev suck(s)

#5 2005-02-19 04:34:18

Re: I/uDev suck(s)

#6 2005-02-19 04:38:22

Re: I/uDev suck(s)

#7 2005-02-19 05:04:36

Re: I/uDev suck(s)

#8 2005-02-19 05:14:43

Re: I/uDev suck(s)

#9 2005-02-19 08:45:00

Re: I/uDev suck(s)

#10 2005-02-21 03:38:35

Re: I/uDev suck(s)

#11 2005-02-21 05:59:19

Re: I/uDev suck(s)

#12 2005-02-21 17:18:52

Re: I/uDev suck(s)

#13 2005-02-21 17:43:14

Re: I/uDev suck(s)

#14 2005-02-21 18:24:21

Re: I/uDev suck(s)

#15 2005-02-23 05:41:43

Re: I/uDev suck(s)

#16 2005-02-23 13:40:15

Re: I/uDev suck(s)

#17 2005-02-23 15:23:32

Re: I/uDev suck(s)

#18 2005-02-24 12:57:43

Re: I/uDev suck(s)

#19 2005-02-25 21:29:25

Re: I/uDev suck(s)

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