pub unsafe extern "C" fn FMOD_System_AttachFileSystem(
system: *mut FMOD_SYSTEM,
useropen: FMOD_FILE_OPEN_CALLBACK,
userclose: FMOD_FILE_CLOSE_CALLBACK,
userread: FMOD_FILE_READ_CALLBACK,
userseek: FMOD_FILE_SEEK_CALLBACK,
) -> FMOD_RESULT