ios - How do I check if the running application on Mac is providing audio output? -

i new question here, though i've seen tons of answers , got helped.

i coding program catch specific audio output among running applications in obj c.

however, i've never touched object c @ all, plus core audio , on, don't know where

i should start project.

can guru in obj c give me direction how start this?

issue: catching specific audio output running application-

for example) running apps : chrome, vlc, itunes , want specify audio output them.