Function async_set_default_dispatcher 

pub unsafe extern "C" fn async_set_default_dispatcher(
    dispatcher: *const async_dispatcher_t,
)

Sets the current thread’s default asynchronous dispatcher interface. May be set to |NULL| if this thread doesn’t have a default dispatcher.

Safety

The caller must ensure that the dispatcher being passed in is currently valid, and that it will remain valid until either the current thread has exited or it has been replaced with another dispatcher (including NULL).