4.5. typedef s3d_cb

typedef void (*s3d_cb)(struct s3d_evt *);

This defines the callback format. Each callback should return void and take an argument of struct s3d_evt *. Callbacks can be defined with s3d_set_callback().

/* a callback handler could look like this: */
void my_key_handler(struct s3d_evt *event_data)
{
	...
}