FUNDAMENTALS OF COMPUTER

Detailed explanation-1: -In computer science, particularly in operating systems, a semaphore is a variable or abstract data type that is used for controlling access, by multiple processes, to a common resource in a parallel programming or a multi user environment.

Detailed explanation-2: -Semaphores are integer variables that are used to solve the critical section problem by using two atomic operations, wait and signal that are used for process synchronization. The wait operation decrements the value of its argument S, if it is positive. If S is negative or zero, then no operation is performed.

Detailed explanation-3: -The implementation of semaphore with a waiting queue may result in a satiation where two more processes are waiting indefinitely for an event that can be caused only by one of the waiting processes. When such a state is reached that process are said to be deadlocked.

Detailed explanation-4: -A semaphore is a value in a designated place in operating system (or kernel) storage that each process can check and then change. Depending on the value that is found, the process can use the resource or will find that it is already in use and must wait for some period before trying again.

Detailed explanation-5: -A. How does the signal() operation associated with monitors differ from the corresponding operation defined for Semaphores? The signal( ) operations associated with monitors is not persistent.