The development about VST Effect

During the development about VST effect[VST2.4], how can I know the counts of tracks has been opened?------------Thank you :smiley: :smiley:

Are you trying to develop a VST effect? Should your post be in the programming section?
I don’t understand what you are asking.

This topic appears to be a duplicate of the topic you started here: https://forum.audacityteam.org/t/the-development-about-vst-effect/38413/1
I am locking this topic to avoid more confusion.