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Restoring the audio preferences without having to run AudioCP

The audio preferences that you can set in the Audio Control Panel are remembered until shutdown or reboot. After booting, the audio preferences (stored in $HOME/.audioCP) are read when AudioCP (the Audio Control Panel) is first run, i.e. audio applications won't use the preferences before the user has manually run AudioCP.

Since workstations are typically shutdown or rebooted only very rarely this is normally not a problem. On the other hand, if you're using a workstation at home, you're probably shutting it down at night—with the effect that you have to run AudioCP every morning.

Here's a small program, asetup, that can be used to set up the preferences without having to run AudioCP. It is intended to be called from a startup file like $HOME/.profile or $HOME/.dt/sessions/sessionetc.

Getting it to work without a network

This is definitely on of the weak points of HP-UX: If your machine is not connected to a network, you'll have trouble getting audio to work.

The problem is that audio relies on the DCE rpcd, which doesn't start if there's no network. Consequently, the audio server (Aserver) fails to start either.

You can always access /dev/audio directly, but you won't be able to use HP's audio software, such as the Audio Control Panel or the Audio Editor. Furthermore, this method is not documented by HP.

To get Aserver to work, you basically have to make the machine believe it's on a network. Plugging a transceiver into the AUI port is reported to work on 715s and 712s (which seem to be the most common standalone systems). You might have to run set_parms again to configure the system as "networked" with an address different from 127.0.0.1. Some people also report that it's necessary for them to have a terminated cable plugged into the transceiver. I recently set up a 715/75 using a transceiver with a terminated T connector.

In a posting to comp.sys.hp.hpux I wrote:

tjevans@junk.raleigh.ibm.com (Tom Evans) writes:

> I'm new to hp-ux, just got a new machine, the rpcd doesn't start
> with no error indications. Tried starting it manually with -f to
> put it in the foreground, but still didn't get messages.
> If there is better place to look for common ( I assume this is a 
> common problem) admin questions I appreciate it. I check the FAQ
> but it didn't have anything specific to rpcd.
> This causes the audio server to fail. 

Is your workstation connected to a network? If it is, it might
indicate that the network setup of your machine is not correct. If it
is _not_ connected to a network you might get rpcd to work by
simulating a network---loopback is not enough. On 715s I have observed
that you need at least a transceiver plugged in and a real
(i. e. non-loopback) network address. The best thing, however, is a
real network.

HP should be aware of this problem with rpcd and fix it, because it's
kind of hard to explain that you don't get audio because you don't
have a network... and of what use is integrated audio if it's harder
to set up than a $20 Soundblaster clone in a lowly PC?

Doug Siebert added the following interesting comment to my last point:

Tried to get them to realize this, but it is a losing battle.  The
audio guys will tell you it is a problem with rcpd, and isn't their
responsibility.  The NCS folks will tell you that rcpd requires a
network because NCS does stand for Network Computing System, after
all, and is pretty useless without a network.  Their support people
recommended just putting a transceiver on the AUI port with nothing
plugged into it.  This works, but it is rather silly to have to do
this.

Rainer Köhler found a different solution:

The good news (at least for me) is that I found a solution:
I restored /usr/audio/*, llbd (don't remember where it lives) and
libAt.* from my 9.05 backup tape.  I replaced rpcd by a symbolic link
to llbd.  Now, the 9.05 programs are able to play and record audio, so
my upgrade was no downgrade in this respect.  The only problem is that
the buttons in the audio_editor don't have any text in them, so one
has to guess which one does what.  Well, you can't have everything.

Note that only HP-UX 9 programs will run with this configuration.

I'll get all this in better shape and maybe add some notes on audio programming when I have more time; until then you might want to check out the full threads via Google Groups.