Many interfaces to the linux kernel are not well documented. Or even if they seem well documented, they can be pretty complex and that can make it hard to understanding what the functional or, often even harder, nonfunctional properties of the interface are. For this reason, my advice to anyone wanting a solid understanding of … Read more
I’ve used it for an in-memory log with a restricted size. For example, the application would write log entries while processing user requests. Whenever an exception occurred (that would be disruptive to the processing) the log records currently in memory would be dumped along with it. The benefit of a circular buffer is, that you … Read more
Strange co-incidence, I just wrote one earlier today! I don’t know what exactly your requirements are but this might be of use. It presents an interface like an Array of unlimited length, but ‘forgets’ old items: // Circular buffer storage. Externally-apparent ‘length’ increases indefinitely // while any items with indexes below length-n will be forgotten … Read more
My colleague Joe, and I believe we have found a simpler way to solve the same problem. In our solution though instead of extending BaseAdapter we extend ArrayAdapter. The code is as follows : public class CircularArrayAdapter< T > extends ArrayAdapter< T > { public static final int HALF_MAX_VALUE = Integer.MAX_VALUE/2; public final int MIDDLE; … Read more
The simplest solution would be to keep track of the item size and the number of items, and then create a buffer of the appropriate number of bytes: typedef struct circular_buffer { void *buffer; // data buffer void *buffer_end; // end of data buffer size_t capacity; // maximum number of items in the buffer size_t … Read more
I would use collections.deque with a maxlen arg >>> import collections >>> d = collections.deque(maxlen=10) >>> d deque([], maxlen=10) >>> for i in xrange(20): … d.append(i) … >>> d deque([10, 11, 12, 13, 14, 15, 16, 17, 18, 19], maxlen=10) There is a recipe in the docs for deque that is similar to what you … Read more