Explain the per thread scoping, Operating System

Assignment Help:

Explain the Per Thread Scoping

Thread-level programming introduces new twists for application-level variable scoping. Threads are commonly used in one of two ways.

  • To execute independent parts of the application program
  • To execute similar application functions on a per-user basis

 

In the latter case, any global variables used by the threads may be subject to modification by more than one thread at a time. Disastrous results may occur if this is left unchecked.

Since threads are potentially executing  the same procedures within an application. Or accessing similar data, per-thread data items may be required.

A common practice in a multithreaded program is  to repentantly call application functions on a per-user or per-function basis. In order to make a function reentrant, variables within the function must either be local or have sterilized access to global data. When executing functions on be half of a user, however, these functions may need access to some user contextual data.

The application developer has one of two choices to make:

  • A variable could be passed to the functions representing an index into a user data structure or a pointer to user data. This is cumbersome, however, because that same variable will need to be passed to each subsequent function so that its scope is visible to application components down the line.
  • The developer can set up a similar variable with the global application scope but with per-threads access. The user data must be unique for each thread and be globally addressable by application functions.

Related Discussions:- Explain the per thread scoping

Operation managmant, what is the function of operation management?

what is the function of operation management?

What is external fragmentation?, What is external fragmentation? As pro...

What is external fragmentation? As process are removed from and loaded to the memory free memory space is bracken into pieces .external fragmentation take place when enough mem

First-in-first-out (fifo), FIFO is named as 'named pipes'. FIFO (first-in-...

FIFO is named as 'named pipes'. FIFO (first-in-first-out) is a special file which is laid to be data transient. Once data is load from named pipe, it cannot be load again. Also, da

Copy on write in virtual memory, how copy on write on pages when many proc...

how copy on write on pages when many process works at a same time?

Long term scheduler, Long term scheduler calculates which processes are a...

Long term scheduler calculates which processes are admitted to the machine for processing. It accepts the degree of multiprogramming. Once accepted, a job converts a process.

Mutual exclusion, With software algorithms for mutual exclusion, such as De...

With software algorithms for mutual exclusion, such as Dekker's algorithm, Peterson's algorithm, or Lamport's bakery algorithm, note that optimizing compilers and out-of-order exec

MICROKERNEL, ADVANTAGES OF MICROFERNEL IN YSTEM DESIGN?

ADVANTAGES OF MICROFERNEL IN YSTEM DESIGN?

What is a semaphore, Question 1: a) State the different file attribute...

Question 1: a) State the different file attributes and briefly explain the operations that can be performed on each files. b) What is a semaphore? Describe why it is impor

List the task regions in the spiral model, List the task regions in the Spi...

List the task regions in the Spiral model.  Customer communication - In this region it is suggested to set up customer communication.  Planning - All planning activities

Differences among user-level threads and kernel-level thread, Q. What are t...

Q. What are two differences among user-level threads and kernel-level threads? Under what situations is one type better than the other? Answer: (1) User-level threads are un

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