From owner-freebsd-multimedia  Sun Mar 23 18:47:06 1997
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Date: Sun, 23 Mar 1997 21:43:34 -0500
From: Randall Hopper <rhh@ct.picker.com>
To: multimedia@freebsd.org
Cc: Steve Passe <smp@csn.net>, Amancio Hasty <hasty@rah.star-gate.com>
Subject: Re: Changes for Audio control on the bt848 code
References: <199703211842.KAA00387@rah.star-gate.com> <199703211908.MAA23449@Ilsa.StevesCafe.com> <19970323210152.33663@ct.picker.com>
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In-Reply-To: <19970323210152.33663@ct.picker.com>; from Randall Hopper on Sun, Mar 23, 1997 at 09:01:52PM -0500
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Its a bad habit to get intro replying to yourself, but...

Randall Hopper:
 |Steve Passe:
 | |whenever any of the picture control values change via ioctl()s each
 | |registered CONTROL_CLIENT is sent a signal by the kernel (say SIG_USR1).

 |Since we already have a file descriptor open for read to the capture device
 |(and now also the tuner device), what about having the driver write out
 |value changes to the open driver file descriptor.  X clients can just

On second thought, buffers could fill up.  Maybe just using activity on the
file descriptor for the "value changed" signaling aspect, and then the
client reading updated values via ioctl or mmaped parameter buffer.

Randall