Problem
Many Unix variants implement an extension known as the "sticky bit". What is its function? (a) On a POSIX system that lacks support for the "sticky bit", how could you achieve an equivalent effect? (b) VerySafe Ltd offer two vaults with electronic locks. They open only after the correct decimal code has been entered. Give one potential advantage and one potential disadvantage of using notify() instead of notifyAll(). [2 marks] (c) Would it have been beneficial to use notify() instead of notifyAll() in your implementation? Justify your answer. 7 (TURN OVER) CST.2019.4.9 10 Prolog In this question you should ensure that your predicates behave appropriately with backtracking and avoid over-use of cut. You should provide an implementation of any library predicates used.
1. Give a suitable state vector for a simple, finite-difference, time domain simulation of the drink system.
2. List the initial values and any other parameters that are needed for the simulation. TLBs and caches are examples of content-addressable memories (CAMs).
3. What is the difference between fully associative, set associative and direct mapped lookup?
Consider the use of a monad for input-output. For the purposes of this question, take the IO monad as including two operations readint and writeint which respectively read integers from stdin and write integers to stdout. Give the types of these operators. [2 marks] (c) Assume MLreadint and MLwriteint are primitives with side effects for inputoutput and consider the ML expression add1 of type int: let val x = MLreadint() in MLwriteint(x+1); x end (i) Give an equivalent expression which uses the IO monad instead of side-effects, and state its type. In each case, would you discard this feature if your employer let you, or insist on retaining it (even covertly) should your employer not value it?