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 debugging a multi threaded program, Debugging a multi threaded prog...

Debugging a multi threaded program The following list points out few of the more frequent oversights and errors that can cause bugs in multithreaded programs. 1.    Ephemeral

Operating system components, Question 1 Discuss the following with respect ...

Question 1 Discuss the following with respect to Operating Systems: Operating System Components Operating System Services Question 2 Describe the theory behind Pagin

What is a thread, What is a thread? A thread or else called a lightweig...

What is a thread? A thread or else called a lightweight process (LWP) is a basic unit of CPU utilization, it comprises of a thread id, a program counter, a register set and a s

What is the information associated with an open file, What is the informati...

What is the information associated with an open file? Various pieces of information are associated with  an open file which may be: File pointer Disk location of th

Describe what is meant by client-server computing, Question 1: (a) Desc...

Question 1: (a) Describe what is meant by Client-server Computing? (b) Distinguish between a server process and a client process. (c) What are the basic characteristics o

Explain operating systems for mainframe computers, What are the main differ...

What are the main differences between operating systems for mainframe computers and personal computers? The design goals of operating systems for those machines are quite diffe

Linux os, Introduction of linux

Introduction of linux

What is an idle thread, idle thread The special thread a dispatcher wi...

idle thread The special thread a dispatcher will run when no ready thread is found. The primary purpose of the idle process and its threads is to remove what would otherwise b

Difference between two tier and three tier architectures, Question: a) ...

Question: a) Illustrate with the help of a diagram, the difference between two tier and three tier architectures. b) Explain in what kind of environment, a peer to peer envi

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