How do I get back a missing device, /dev/dsp?

What does the block device refer to?

I'm not quite sure what you mean. In /dev, there is no dsp. This in 11.04. However, on my old Thinkpad I cd'd to /dev and:

kline@zen:/dev$ ls -ls dsp
0 crw-rw----+ 1 root audio 14, 3 2011-07-13 16:29 dsp
kline@zen:/dev$

PS: on my desktop, this:

pts/18 12:53 <tao> [5046] ls -ls /dev/dsp
ls: cannot access /dev/dsp: No such file or directory
pts/18 12:53 <tao> [5047]

So you are having a sound issue?

I am trying to cat a wav file thru one of the devices in /dev. I am able to cat the file to /dev/dsp on 08.04. A small C program I wrote opens /dev/dsp and send audio files out thru /dev/dsp. Both on my server, FreeBSD as well as my older Ubuntu. I'm trying to figure out how to get /dev/dsp back on my desktop. Or what other /dev to use.

Do you have normal sound?

Yes. Two speakers [on desktop].

/dev/dsp is the OSS (open sound system) device -- this sound system has been deprecated for quite some time. Applications need to move away from using /dev/dsp to ALSA based sound mixing.

https://secure.wikimedia.org/wikipedia/en/wiki/Open_Sound_System

Ubuntu removed legacy OSS devices from its kernel. You can try to emulate OSS with padsp, or you can actually support the OSS crew and get an OSS license (I recommend that).

sorry for the delay. my domain was kknocked out by a power surge and it is not easy getting down from my wheelchair and crawling around, and finally hauling my dead-weight back up.

re the sound problem, since the kernel guys pulled /dev/dsp i'm going to pass.

ii have done some kernel hacking on the BSD kernel; i have written only three drivers in my career--they were the kind of thing that i wish to avoid! most of my career was spent doing porting and in os test, plus kernel hacking on supercomputers. anything audio and video is a black box. so i'll leave it there.