Re: HAL Devices and Streams (with QuickTime)
Re: HAL Devices and Streams (with QuickTime)
- Subject: Re: HAL Devices and Streams (with QuickTime)
- From: Jeff Moore <email@hidden>
- Date: Fri, 18 Jan 2002 14:34:45 -0800
on 1/18/02 1:09 PM, Lieven Dekeyser <email@hidden> wrote:
>
If you know exactly how many output devices your app will need, for
>
instance 2, (like for my app: main output & monitor) a quick & dirty
>
solution would be to install 2 Components in the OS which are exact copies
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of the HAL Output Component except for their id (componentSubType,
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componentManufacturer), right? this way, the Soundmanager would look at
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them as 2 different Components (not just 2 different instances of the
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same Component), and you would be able to use both...
This would work, as long as the device didn't go away while you were using
it.
>
but I guess there's
>
no way of copying the HAL Output Component, is there?
You could make an sdev that delegated all it's calls to an instance of the
HAL sdev in it's dispatcher.
This kind of construct should cover you 90% of the time. The places where
you'll be tripped up is the boundary conditions, like the device going away.
It's much easier to make this work for your specific application than it is
to make it work on a general basis.
--
Jeff Moore
Core Audio
Apple