Load a supported audio format into a music object.
int freesrc);Mix_Music * Mix_LoadMUS_RW(SDL_RWops *src,
an SDL_RWops that data will be read from.
non-zero to close/free the SDL_RWops before returning, zero to leave it open.
Returns a new music object, or NULL on error.
SDL_mixer has two separate data structures for audio data. One it calls a "chunk," which is meant to be a file completely decoded into memory up front, and the other it calls "music" which is a file intended to be decoded on demand. Originally, simple formats like uncompressed WAV files were meant to be chunks and compressed things, like MP3s, were meant to be music, and you would stream one thing for a game's music and make repeating sound effects with the chunks.
In modern times, this isn't split by format anymore, and most are interchangeable, so the question is what the app thinks is worth predecoding or not. Chunks might take more memory, but once they are loaded won't need to decode again, whereas music always needs to be decoded on the fly. Also, crucially, there are as many channels for chunks as the app can allocate, but SDL_mixer only offers a single "music" channel.
freesrc is non-zero, the RWops will be closed before returning, whether this function succeeds or not. SDL_mixer reads everything it needs from the RWops during this call in any case.
As a convenience, there is a function to read files from disk without having to deal with SDL_RWops:
("filename.mp3") will manage those details for you.
This function attempts to guess the file format from incoming data. If the caller knows the format, or wants to force it, it should use Mix_LoadMUSType_RW() instead.
When done with this music, the app should dispose of it with a call to Mix_FreeMusic().
This function is available since SDL_mixer 2.0.0.