Question on File Systems and Management.

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Question Bank
2.1 For the file extensions given below indicate the corresponding file type and the usually associated purpose.
a. BAT , exe, zip, au
b. bin, lib, tex, gif, ar
2.2 Describe the file system organization. Describe how file hierarchy is managed?
2.3 Describe at least three file operations.
2.4 Interpret the following instructions:
a. ls -a ,
b. rm a*
c. cp ?aa* ?ab*
2.5 What is the short cut to move up one level from current directory?
2.6 What happens when you give a command: touch a_file?
2.7 Describe the interpretation of the following under the command chmod:
a. 444
b. 111 001 101
2.8 Describe an encryption method provided in Unix to secure files. How does one
retrieve an encrypted file using an encryption command? Explain the basic
principle.
2.9 Describe briefly
a. The methods of file accessing.
b. Two level directory structure.
2.10 What is the role of an inode?
2.11 Describe the structure of Inode in UNIX. What entries undergo changes when a
file is opened to read / write / copied / renamed.
2.12 What is an I-node and what role does it play.
2.13 What corresponds to i-node in the MS environment?
2.14 What is a root file system?
2.15 List the various disk space allocation strategies. Explain clearly the contiguous allocation technique.
P.C.P.Bhat/IISc Bangalore M2/V1/June 04/2
2.16 Compare and contrast chained allocation with indexed allocation technique of file
allocation
2.17 Define external and internal fragmentation
2.18 What are the different types of files? What are the tasks of the file management
system? List some (at least two) file system related commands in UNIX? How
does OS ensure security in file system?

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