Re: [SLUG] /dev/mixer, /dev/dsp

From: Derek Glidden (dglidden@illusionary.com)
Date: Mon Jul 02 2001 - 11:03:50 EDT


Norbert Omar Cartagena wrote:
>
> Derek Glidden wrote:
> >
> > Does RedHat 7.1 use devfs by default? I haven't used either RedHat 7.1
> > or devfs, but it's possible that that's the cause of your woes.
> >
>
> 1) Yes, it does use it.

Interesting...
 
> 2) How/Why is it the cause?

devfs dynamically creates all its device nodes in the same way procfs
makes all those "fake" files in /proc. It's a "pseudo-filesystem" mount
type thing.

There has been a lot of "controversy" (for lack of a better term) on
LKML regarding devfs and how one would accomplish the most basic of
adminstration tasks like creating a new devnode and changing permissions
considering everything in devfs "goes away" when you shutdown or reboot
your machine.

So you can't just mknod /dev/dsp or /dev/audio in a devfs /dev
directory, the same way you can't store stuff in /proc.
 
> 3) How do I go about fixing this? Or will it require that you set up
> your cauldron in front of my laptop at the meeting and perform some
> magik?

Actually I've never played with devfs, so I'm not really sure myself.

An alternative is not to use devfs until you're more comfortable with
it. Look for the entry in /etc/fstab that mounts /dev/ as a 'devfs'
type filesystem, remove it, and start dealing with /dev the
"old-fashioned way".
 
> Thanks for pointing me in the right direction,

No worries.

-- 
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#!/usr/bin/perl -w
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[$_%8]}(16..271);if((@a=unx"C*",$_)[20]&48){$h=5;$_=unxb24,join
"",@b=map{xB8,unxb8,chr($_^$a[--$h+84])}@ARGV;s/...$/1$&/;$d=
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print+x"C*",@a}';s/x/pack+/g;eval 

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