What are semaphores, Computer Engineering

Assignment Help:

What are semaphores?

Semaphore: A semaphore is a synchronization tool which gives a general-purpose solution to controlling access to critical sections. It s an abstract data type (ADT) which defines a nonnegative integer variable that, apart from initialization, is accessed simply through two standard operations that are: wait and signal. The typical definition of wait in pseudo code is

wait(S){

          while(S<=0)

                 // do nothing

                          S--; }

The classical definitions of signal in pseudo code is signal(S){

                    S++; }

While one process modifies the semaphore value, anno one process can concurrently modify that similar semaphore value. As well, in the case of the wait(S), the testing of the integer value of S (i.e. S<=0), and its possible modification(S--), should also be executed without interruption.


Related Discussions:- What are semaphores

4 bit comparator, how to breadboARD THE 4 BIT COMPARATOR

how to breadboARD THE 4 BIT COMPARATOR

Determine the values of the output of the logic gates, Write the values of ...

Write the values of the C output for the following gates: For a(n) ________ gate, the output is zero if any of the inputs are equal to  one. For a(n) ________ gate ,the

How do active web pages work, How do active web pages work? Describe with a...

How do active web pages work? Describe with a small example. Active Web Pages: An active document is not completely specified through the server. Instead an active documen

Explain hypertext transfer protocol, Explain Hypertext Transfer Protocol. ...

Explain Hypertext Transfer Protocol. HTTP is used mainly in today's society like a set of rules for exchanging files (graphic images, text, sound, other multimedia files or vid

Illustrate the advantages of encapsulation, Advantages of Encapsulation ...

Advantages of Encapsulation You can also delay the resolution of the details until after the design.  You can keep your code modular.

What is instruction register, Q. What is Instruction Register? Instruct...

Q. What is Instruction Register? Instruction Register (IR): Here instructions are loaded before execution. Comments on figure above are as below: All representations are

Vector processing with pipelining-vector processing, Vector Processing with...

Vector Processing with Pipelining: Since in vector processing, vector instructions perform the similar computation on dissimilar data operands repeatedly, vector processing is most

How steps of instruction execution can be broken down, Q. How steps of inst...

Q. How steps of instruction execution can be broken down? Let's explain how these steps of instruction execution can be broken down to micro-operations. To make easier this dis

Give the truth table of S-R and D-flipflops, Give the truth table of S-R an...

Give the truth table of S-R and D-flipflops. Ans: The Truth Table for S-R Flip-Flop is illustrated in Fig.(a) and truth table of D Flip-Flop is illustrated in Fig.(b)

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd