Re: /dev/dsp disappeared after power outage


On Feb 4, 2008, at 14:52 , Ulrich Spoerlein wrote:

On Mon, 04.02.2008 at 13:00:40 -0700, Bert JW Regeer wrote:
On Feb 4, 2008, at 08:03 , John Baldwin wrote:
On Saturday 02 February 2008 06:40:15 pm Aryeh M. Friedman wrote:
I just had a power outage and when it came back /dev/dsp0.0 was
missing from the devices. the kern module loaded fine and detected
the card correctly (according to dmesg, sysctl and /dev/sndstat) but
neither the above or /dev/pcm exists. After rebooting the problem
remains. Any ideas how to fix it?

Nothing to fix. This is how devfs device cloning works.

Nothing to fix? The sound card that is correctly detected by the kernel
module is not being created in /dev, ONLY after he had a power outage. It is
not even coming back when he reboots the machine.

I don't have any suggestions, I just don't believe "Nothing to fix" is the
right answer.

Sigh,

AFAIK dev cloning works by creating the device nodes when open()ed.
Using 'ls /dev/dsp*' will not open() any devices, so nothing is created.
He should use 'ls /dev/dsp0 /dev/dsp0.0' and then the devices should
appear.

Try it for yourself, do 'ls /dev/dsp*' then 'ls /dev/dsp.8'

Not that anything usefull can be done with ls(1) to get sound :)


Cheers,
Ulrich Spoerlein
--
It is better to remain silent and be thought a fool,
than to speak, and remove all doubt.


I just booted up my desktop machine at home, I don't have sound enabled by default, so I loaded the module that is required. Before the module was loaded:

ls -lah /dev/dsp*
ls: No match.

After the module was loaded (I just load snd_driver). Nothing else was executed after the module was loaded.

ls -lah /dev/dsp*
crw-rw-rw- 1 root wheel 0, 106 Jan 26 05:24 /dev/dsp0.0
crw-rw-rw- 1 root wheel 0, 109 Jan 26 05:24 /dev/dsp0.1
crw-rw-rw- 1 root wheel 0, 112 Jan 26 05:24 /dev/dsp0.2
crw-rw-rw- 1 root wheel 0, 115 Jan 26 05:24 /dev/dsp0.3
crw-rw-rw- 1 root wheel 0, 118 Jan 26 05:24 /dev/dsp0.4
crw-rw-rw- 1 root wheel 0, 122 Jan 26 05:24 /dev/dsp0.5
crw-rw-rw- 1 root wheel 0, 107 Jan 26 05:24 /dev/dspW0.0
crw-rw-rw- 1 root wheel 0, 110 Jan 26 05:24 /dev/dspW0.1
crw-rw-rw- 1 root wheel 0, 113 Jan 26 05:24 /dev/dspW0.2
crw-rw-rw- 1 root wheel 0, 116 Jan 26 05:24 /dev/dspW0.3
crw-rw-rw- 1 root wheel 0, 119 Jan 26 05:24 /dev/dspW0.4
crw-rw-rw- 1 root wheel 0, 123 Jan 26 05:24 /dev/dspW0.5
crw-rw-rw- 1 root wheel 0, 121 Jan 26 05:24 /dev/dspr0.4

So what gives?

Bert JW Regeer

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