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

Computers, What is operating system?

What is operating system?

Give an overview of windows 2000 file management, Give an overview of WINDO...

Give an overview of WINDOWS 2000 file management. Windows makes use of the NTFS and File Allocation Table file systems. The Older versions of the FAT file system had file name

Briefly explain about file system implementation, Briefly explain about fil...

Briefly explain about file system implementation? Several on-disk and in-memory structures are used to execute a file system. On disk, the file system may have information abou

What is co-operative process, What is co-operative process? A process i...

What is co-operative process? A process is co-operating if it can influence or be affected by the other processes implementing in the system. Any process that share data with o

Explain concept of synchronization, Synchronization In communication am...

Synchronization In communication among processes messages passed may be blocking or nonblocking - also called as synchronous and asynchronous. Blocking send : The sending pr

Explain rehashing to handle collision, Explain Rehashing to Handle Collisio...

Explain Rehashing to Handle Collision Rehashing:  Re-hashing schemes make use of a second hashing operation while there is a collision. If there is an additional collision, we

What is banker''s algorithm, What is banker's algorithm? Banker's algor...

What is banker's algorithm? Banker's algorithm is a deadlock avoidance algorithm that is applicable to a resource-allocation system with multiple examples of each resource type

What is process control block, What is process control block? Every pro...

What is process control block? Every process is represented in the OS by a process control block. It has many pieces of information associated with an exact process.

Activities of operating system-secondary-storage management, Q. What are th...

Q. What are the three main activities of an operating system in regard to secondary-storage management? Answer: 1) Free-space management 2) Storage allocation 3) Disk

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