why SDL_GetNumAudioDevices( SDL_TRUE ) mistake with number of recording device in sdl2 c++ program

Moved to Music/SFX. This question was off-topic in the Writing For Games forum.

This looks like a programming question. I thought the Music/SFX forum was for creating audio content, not audio programming?

Agreed, while there is some overlap between game audio and programming, most of the audience here is content oriented. Moving this to programming.