coreaudio::audio_unit::render_callback::action_flags::OUTPUT_IS_SILENCE

pub const OUTPUT_IS_SILENCE: ActionFlags = ActionFlags{bits: au::kAudioUnitRenderAction_OutputIsSilence,}

This flag can be set in a render input callback (or in the audio unit's render operation itself) and is used to indicate that the render buffer contains only silence. It can then be used by the caller as a hint to whether the buffer needs to be processed or not.

Available in OS X v10.2 and later.