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

Logical user-centered interactive design methodology, Question: Logical...

Question: Logical User-Centered Interactive Design Methodology is a methodology that identifies six clear stages to help in software development while keeping the user in mind.

Explain input - output techniques, Q. Explain the Hard Disk Controller & F...

Q. Explain the Hard Disk Controller & Floppy Disk Controller with necessary diagrams. Q. Explain Input/Output Techniques (Data Transfer Techniques).

Why select clause comes after from clause in linq, The reason is, LINQ is u...

The reason is, LINQ is used with C# or other programming languages, which needs all the variables to be declared first. From clause of LINQ query just describes the range or condit

Prints the hundreds digit in two integers , Write an application that prin...

Write an application that prints the hundreds digit  in two integers read from the keyboard. For example if the data values are 1456 and 255 respectably, output should include the

What are the uses of interrupts, What are the uses of interrupts?  ...

What are the uses of interrupts?  Recovery from errors Debugging Communication among programs Use of interrupts in operating system

C, Drawbacks of linear arrays

Drawbacks of linear arrays

What is block scope, What is Block scope Block scope: The variables w...

What is Block scope Block scope: The variables with block scope appear in a block or within the list of formal parameter declarations in a function definition. It is visible

Explain difference between space and time division switching, Through two b...

Through two block diagrams explain the difference between Space division and time division switching. Space and Time Switching: Space Switches: Connections can be made i

Define hit ratio, Define Hit ratio. The performance of cache memory is ...

Define Hit ratio. The performance of cache memory is frequently measured in terms of quantity called hit ratio. Hit-Find a word in cache. Miss-Word is not found in cache.

Universal elimination, Universal Elimination: Here for any sentence, t...

Universal Elimination: Here for any sentence, there is A, containing a universally quantified variable, v, just for any ground term, g, so we can substitute g for v in A. Thus

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