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

Fcfs scheduling algorithm, Q. Presume that the following processes arrive f...

Q. Presume that the following processes arrive for execution at the times indicated. Every process will run the listed amount of time. In responding the questions use non pre-empti

Assignment, You must use fork and pipe to complete this project. This proj...

You must use fork and pipe to complete this project. This project creates processes to add all numbers in a file. The user will enter a number (1, 2, or 4) of parallel processes

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

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

Define process? what is meant by state of a process?, Define process? What ...

Define process? What is meant by state of a process? Process is a program in implementation. A process in general includes the process stack, which consists temporary data and

Prolog application, 1. Problem Domain You will be considering the Wumpus ...

1. Problem Domain You will be considering the Wumpus world introduced in Russell and Norvig (2009) Chapter 7. For this programming assignment you'll use Prolog's ability to do in

How can the deadlock be prevented-safe state, How can the deadlock be preve...

How can the deadlock be prevented-Safe State Safe state : A state is safe if the system is able to allocate resources to each process in some order and still avoid deadlock.

Dual Mode Operation, I am not getting what you have tried to describe here....

I am not getting what you have tried to describe here. Can you elaborate more about this, i will be thankful to you. Vinay

What happens when you execute a program in unix, When you run a program on ...

When you run a program on your UNIX system, the system prepares a special environment for that program. This environment owns everything needed for the system to execute the progra

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