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

Explain analysis and synthesis phase of a compiler, Explain analysis and sy...

Explain analysis and synthesis phase of a compiler. The synthesis and analysis phases of a compiler are: Analysis Phase: In this breaks the source program in constituent

How to call a wml script from a wml page, WML & WML Script 1. How to ca...

WML & WML Script 1. How to call a WML Script from a WML Page? 2. Write a brief note on WML Script Operators and Expressions. 3. Write brief notes on WML Script Statements

What is software engineering, Software engineering is:- The application...

Software engineering is:- The application of a disciplined engineering move towards to the development of software systems. A body of information and knowledge in software d

What is electronic cash, What is electronic cash? E-cash is cash which ...

What is electronic cash? E-cash is cash which is shown by two models. One is the on-line form of e-cash which permits for the completion of all types of internet transactions.

What is the prominence of rs232-c in serial communication, What is the prom...

What is the prominence of RS232-C in serial communication?  Name some application where you see its use.  RS-232 stands for Recommend Standard number 232 and C is the latest re

Explain clearly the kuleshov experiment, Question: (a) Write a proposal...

Question: (a) Write a proposal for a 10-11 minutes movie of your choice with the expected content. (b) Explain clearly the "Kuleshov Experiment" (c) Give the checklist be

Don''t care states, The conflict between too hot and too cold or too slow a...

The conflict between too hot and too cold or too slow and too fast can be resolved using don't care states. Don't care states are used when i) the state of the output is not

Planning too much up front a mistake in an oosad, You can't plan only for t...

You can't plan only for the present phase of the project as your future activities are still coarse granular. To have good planning you require to have fine granularity w.r.t the t

Engineering and scientific software, Engineering and Scientific Software ...

Engineering and Scientific Software Engineering  and  Scientific  software  has  been  characterized  with "number crunching" algorithms. Application starts from astronomy t

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