Explain two level directory, Operating System

Assignment Help:

Two Level Directory

This kind of structure overcomes the problems of assigning unique names to the files. Thus there need not be any confusion among users.

In this kind of structure each user has a user file directory (UFD). The UFDs have an alike structure except each lists the files of a single user. As soon as a user starts or logs in the system's master file directory (MFD) is searched. The MFD is indexed by the account number or the user name and each entry points to the UFD for that user. Once a user searches for a particular file only his own UFD is searched and so different users may have the same names as long as all the file names within each UFD are unique.

A two level directory is able to be thought of as an inverted tree of height 2. The root of the tree is the MFD in addition to its descendents are the UFDs whose descendents are the files. 

Disadvantages:

            This structure detaches one user from the other. This is an benefit when the users are completely independent of each other but is a drawback when the users want to cooperate on some task and to access one another's files.

 

2000_Two Level Directory.png


Related Discussions:- Explain two level directory

Explain briefly the working of semaphore with example ?, Explain briefly th...

Explain briefly the working of semaphore with example ? The E.W. Dijkstra (1965) abstracted the key idea of mutual exclusion in his concepts of semaphores. Definition A s

Page fault handling , Page Fault Handling conditions like, where the copy...

Page Fault Handling conditions like, where the copy on write bit of a page is set and that page is send by more than one process, the Kernel assign new page and copies the conten

Explain the concept of mutual exclusion, Question 1: (a) Discuss about...

Question 1: (a) Discuss about the evolution of operating systems from mainframe batch systems to mainframe time sharing systems. (b) Explain your understanding of the "sus

Explain tightly coupled systems and loosely coupled system, Differentiate t...

Differentiate tightly coupled systems and loosely coupled systems? Loosely coupled systems:-  Every processor has its own local memory  Every processor can communicate

Define different multithreading models, DIFFERENT MULTITHREADING MODELS ...

DIFFERENT MULTITHREADING MODELS Multithreading Models the majority multithreading models fall into one of the following categories of threading implementation: 1.      M

What is the concept of an atomic operation, Question: Concurrency and Sync...

Question: Concurrency and Synchronization a) Define the following terms: I. Critical section II. Mutual Exclusion III. Deadlock IV. Starvation. b) Name three methods w

Effects of multiprogramming on resource utilization, Effects of multiprogra...

Effects of multiprogramming on resource utilization With the utilize of multiprogramming, batch processing is able to be quite efficient .Just as multiprogramming permits the

Explain the facilities of a debug monitor, Facilities of a Debug Monitor ...

Facilities of a Debug Monitor Facilities of a debug monitor are like this: Setting breakpoints in the program Initiating a debug conversation while control reaches

Define a election algorithm, Consider a setting where processors are not as...

Consider a setting where processors are not associated with unique identifiers but the total number of processors is known and the processors are organized along a bidirectional ri

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