What do you mean by semaphore?, Operating System

Assignment Help:

What do you mean by semaphore? 

Semaphore: A synchronization variable that acquires on positive integer values. Invented by the Dijkstra

  • P (semaphore): an atomic process that waits for semaphore to turn into positive then decrements it by 1.
  • V (semaphore): It is an atomic process that increments semaphore by 1.

The names arrive from the Dutch, verhogen (increment) and proberen (test). Semaphores are elegant and easy and permit the solution of many interesting problems. They do many more than just mutual exclusion.

 


Related Discussions:- What do you mean by semaphore?

Fork system call in unix, Forking is an important phase of Unix, critical t...

Forking is an important phase of Unix, critical to the support of its design strategies, which encourages the implementation of filters. In Unix, a filter is a process that reads i

Bankers algorithm, p0A B C D A B C D A B C D 2 0 12 2012 1000 1354 0632 ...

p0A B C D A B C D A B C D 2 0 12 2012 1000 1354 0632 0014

Paging, what is the use of valid invalid bits in paging

what is the use of valid invalid bits in paging

What is sector sparing, What is sector sparing? Low-level formatting al...

What is sector sparing? Low-level formatting also sets aside extra sectors not visible to the operating system. The controller can be told to change each bad sector logically w

Mechanism for code and data sharing, Q. Consider a system in which a progr...

Q. Consider a system in which a program is able to be separated into two parts: code and data. The CPU recognizes whether it wants an instruction (instruction fetch) or data (data

Explain the spawnlp functions used in the netware, Explain the Spawnlp Func...

Explain the Spawnlp Functions Used in the NetWare Spawnlp(flags, execName, arg0,...)  The Spawnlp function is used to load  a NetWare executable file (NLM) specified by exec

Show the multithreading performance, Q. Provide two programming instances i...

Q. Provide two programming instances in which multithreading provides better performance than a single-threaded solution. Answer: (1) A Web server that services every request

List sample file types, List sample file types, based on use, on the VAX un...

List sample file types, based on use, on the VAX under VMS.  source programs (.BAS, .FOR, .COB, .PLI, .PAS, .MAR)  data files (.DAT)  text files (.TXT)  command proced

Components of an operating system-control programs, CONTROL PROGRAMS Co...

CONTROL PROGRAMS Control Programs are those programs which control & maintain the operation of computer. They provide basic facilities. Control program are further divided into

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