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| -rw-r--r-- | SSVLSystemAlertVolume.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/SSVLSystemAlertVolume.c b/SSVLSystemAlertVolume.c index 4f6c270..8e50195 100644 --- a/SSVLSystemAlertVolume.c +++ b/SSVLSystemAlertVolume.c @@ -10,6 +10,13 @@ #include "SSVLSystemAlertVolume.h" +// This property appears to be private, as it isn't defined in Apple's MacOSX +// SDK framework headers. +// +// The value comes from the Sound preference pane. Disassembling the +// `/System/Library/PreferencePanes/Sound.prefPane/Contents/MacOS/Sound` binary +// shows that functions accessing the system alert volume do so via the +// '0x7373766c' property. Converting that to a FourCharCode yields 'ssvl'. const AudioServicesPropertyID SSVLAudioServicesPropertySystemAlertVolume = 'ssvl'; OSStatus SSVLGetSystemVolume(Float32 *volume) { |