How to programmatically sense the iPhone mute switch?

Question

I can't seem to find in the SDK how to programatically sense the mute button/switch on the iPhone. When my app plays background music, it responds properly to the volume button without me having any code to follow that but, when I use the mute switch, it just keeps playing away.

How do I test the position of mute?

(NOTE: My program has its own mute switch, but I'd like the physical switch to override that.)

Answer

Thanks, JPM. Indeed, the link you provide leads to the correct answer (eventually. ;) For completeness (because S.O. should be a source of QUICK answers! )...

// "Ambient" makes it respect the mute switch
// Must call this once to init session
if (!gAudioSessionInited)
{
    AudioSessionInterruptionListener    inInterruptionListener = NULL;
    OSStatus    error;
    if ((error = AudioSessionInitialize (NULL, NULL, inInterruptionListener, NULL)))
    {
        NSLog(@"*** Error *** error in AudioSessionInitialize: %d.", error);
    }
    else
    {
        gAudioSessionInited = YES;
    }
}

SInt32  ambient = kAudioSessionCategory_AmbientSound;
if (AudioSessionSetProperty (kAudioSessionProperty_AudioCategory, sizeof (ambient), &ambient))
{
    NSLog(@"*** Error *** could not set Session property to ambient.");
}