Weird hidden /dev/audio on devfs

[Pavel Roskin]

Hello!

I'm using 2.4.0-ac11 with devfs support. Something is very strange in the
way how devfs behaves with respect to OSS sound drivers.

devfsd version 1.3.10 is running. There is an entry "alias /dev/audio
/dev/sound" in modules.devfs, which is the default.

If the "sound" module is not loaded, there are no files named "audio"
under /dev:

[proski@fonzie /dev]$ ls -al audio
ls: audio: No such file or directory
[proski@fonzie /dev]$ ls -alR | grep audio
[proski@fonzie /dev]$

Now I load sound.o and strange things begin:

[proski@fonzie /dev]$ ls -al audio
lr-xr-xr-x    1 root     root           11 Jan 24 18:08 audio ->
sound/audio
[proski@fonzie /dev]$ ls -alR | grep audio
crw-rw--w-    1 root     root      14,   4 Dec 31  1969 audio
[proski@fonzie /dev]$

/dev/audio exists when named explicitly, but otherwise only
/dev/sound/audio can be found.

No sound-card specific modules are loaded at this point:

[proski@fonzie /dev]$ /sbin/lsmod
Module                  Size  Used by
sound                  60880   0 (unused)
soundcore               4240   2 [sound]
mga                    95424   1
agpgart                14080   3
floppy                 46384   0 (autoclean)
[proski@fonzie /dev]$

All relevant config files are here:
http://www.red-bean.com/~proski/sound_devfs/

Regards,
Pavel Roskin