Explain acyclic graph directories and its implementation, Operating System

Assignment Help:

Acyclic Graph Directories

In this kind of directory structure the shared directories or files can exist in the file system in two or more places at once. A tree structure excludes the sharing of files or directories. An acyclic graph namely a graph with no cycles allows directories to share subdirectories and files. The acyclic graph is a usual generalization of the tree structured directory scheme. It is more flexible in comparison of a simple tree, but it is as well more complex.

A directory or shared file isn't the same as two copies of the same file or directory. With two copies if one copy is changed subsequently the changes will not be reflected in the other copy. With a shared file, the alterations made by one person are immediately visible to the other. Sharing is a significant concept for subdirectories. A fresh file created by one person will automatically come into view in all the shared subdirectories.

Implementation:       

Directories and Shared files can be executed by creating a new directory entry called link which points to another subdirectory or file. When a reference to a file is made then the directory is searched. If the directory entry is marked like a link after that the name of the real file is included in the link information. The link is resolve by using the path name to locate the real file.

Another method is to copy (duplicate) all information about shared files in both the sharing directories.

 

2270_Acyclic Graph Directories.png

 

                                                                                  Acyclic Graph directory structure


Related Discussions:- Explain acyclic graph directories and its implementation

Explain linked allocation, Linked allocation With linked allocation, ev...

Linked allocation With linked allocation, every file is a linked list of disk blocks; the disk blocks might be scattered anywhere on the disk. The directory has a pointer to th

System structures, advantages and disadvantages of monolithic and layered a...

advantages and disadvantages of monolithic and layered approach

Explainoptimal page replacement in detail, Optimal page replacement An...

Optimal page replacement An optimal page replacement algorithm has the least page fault rate of all algorithms. The algorithm states that put back the page that will not be us

How the nested macro calls are expanded, How the Nested Macro calls are exp...

How the Nested Macro calls are expanded LIFO (Last in First out)

Explain the tlsgetvalue (tlsindex) function, Explain the TlsGetValue (TLSin...

Explain the TlsGetValue (TLSindex) Function Executing this function will return the thread local storage data associated with this thread. The pointer returned will be the one

List antivirus techniques used for protection purposes, Question: a) Th...

Question: a) There are main goals of data security. List them and elaborate on how they provide protection. b) Describe threats associated with data security. c) Describe

search tree generated by hill-climbing search, Show the search tree genera...

Show the search tree generated by Hill-Climbing search (text figure 4.2, page 122; or Local Search lecture, slide 6) for each of the two heuristics (a) and (b) applied to the follo

Explain the proper distribution of functionality and code, Explain the Prop...

Explain the Proper Distribution of Functionality and Code It is important to note that the bandwidth of the server operating system and server processor availability is fixed.

What is sector sparing, What is sector sparing? Low-level formatting al...

What is sector sparing? Low-level formatting also sets aside extra sectors not visible to the operating system. The controller can be told to change each bad sector logically w

Operating system structure, Problem: (a) Modern operating systems are i...

Problem: (a) Modern operating systems are interrupt driven. If there are no processes to execute, no I/O devices to service, and no users to whom to respond, an operating syste

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