Ceremony of the Keys (London) passes his lantern to a soldier, and marches with his escort to the outer gate. The sentries on duty salute the Queen’s Keys as they pass. The Warder first locks the outer gate and then the gates of the Middle and Byward Towers. The Warder and escort march down Water Lane, until they reach the Bloody Tower archway where a sentry challenges the party to identify themselves: The Warder and escort march down to the foot of Broadwalk Steps where the main Tower Guard is drawn up to meet them. The party halts, and the officer in charge gives the
Locks-and-keys Locks-and-keys Locks-and-keys is a solution to dangling pointers in computer programming languages. The locks-and-keys approach represents pointers as ordered pairs (key, address) where the key is an integer value. Heap-dynamic variables are represented as the storage for the variable plus a cell for an integer lock value. When a variable is allocated, a "lock value" is created and placed both into the variable's cell and into the pointer's key cell. Every access to the pointer compares these two values, and access is allowed only if the values match. When a variable is deallocated, the key of its pointer is modified