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To: John-Mark Gurney <gurney_j@resnet.uoregon.edu>
cc: Mark Murray <mark@grondar.za>, multimedia@FreeBSD.ORG
Subject: Re: GUS PnP woes 
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Date: Sat, 21 Jun 1997 14:56:31 +0200
From: Mark Murray <mark@grondar.za>
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John-Mark Gurney wrote:
> > Two processes can't open /dev/audio. How should this work?
> 
> see below, they can if one is a child of another...
> 
> > Speak_freely has one process doing the reading and one doing the 
> > writing. The one that starts second cannot get /dev/audio because it is 
> > busy. This can be duplicated by going 'cat /dev/audio > /dev/audio'.
> 
> so you simply do something like:
> 
> int fd;
> fd=open("/dev/audio", O_RDWR);
> if(fork()) {
> 	handle one end;
> } else {
> 	handle the other;
> }

AAAHHH! Does this not therefore represent breakage of the original 
FULL-DUPLEX model of /dev/audio (as required by eg. speak_freely)?

> really quite simple...  and the seperate audio{0,1} was probably so you
> could simulate full duplex audio with two sound cards... one as audio0
> and the other as audio1...

OK. ATM, if I cat a .au file to /dev/audio1, my system panics with an 
integer overflow. I dont know enough about what I am doing to tell 
whether this is a real problem or pilot error.

M
--
Mark Murray
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