Newsgroups: comp.unix.shell
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!uupsi!citib.com!scairns
From: scairns@citib.com (Scott Cairns)
Subject: Audio
Message-ID: <1991Jun7.134254.11485@citib.com>
Keywords: Audio Shell
Sender: news@citib.com
Reply-To: scairns@citib.com (Scott Cairns)
Organization: US Card Products Group, Citicorp
Distribution: usa
Date: Fri, 7 Jun 91 13:42:54 GMT


I posted something the other day about how one could take stdout
from something like record(6) and pipe it out over the network
to another host's audio device.   The following was suggested
by <barmar@Think.COM>:

>       % record | rsh [hostname] play
>
>	This should turn the two hosts and the network into telephones.
>
>	-- 
>	Barry Margolin, Thinking Machines Corp.

which worked just fine.  He then followed up with this question:

>	I was curious about how well this would work.  Is the bandwidth of
>	Ethernet good enough for real-time sound like this?
>	

It's not exactly "real-time" of course.  With:

% record -v 50 | rsh [hostname] play -v 50

you have to wait for record(6) to do a flush(3) before it pipes
over the network to rsh(1) so there is a second or two of latency.

So I'm not sure if I can answer the bandwidth question (i.e. it
may be a moot point).

Does anyone have any comments regarding the bandwidth issue and
also is it possible to remove the delay inherent in the above
example?

BTW, I haven't figured out a practical application yet for any of
this yet.  I suppose you could announce something like "The
server is coming down..." but you'd need to be able to rsh to 
multiple hosts at the same time.  Any suggestions would be
welcome...

+-----------------------------------------------------------------+
| Scott Cairns, AVP      	    email: scairns@bank.citib.com |
| Citicorp Credit Services Inc.     phone: (718) 248-5366	  |
| Long Island City, NY  11120	      fax: (718) 248-6855         |
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| Disclaimer:  I speak for myself only - not that anyone here     |
| would understand what I'm saying anyway.			  |
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