2. What is the purpose of grep command? Explain the various options available with

the grep command with an example. [4+8+4]

3. Explain the following functions with syntax:

(a) stat()

(b) read()

(c) open()

(d) fstat() [4x4=16]

4. Suppose a process does not wish to block until its children terminate. How can it

ensure that child processes are cleaned up when they terminate? [16]

5. (a) Write about the signals implementation. Write about “sigpending”, “sigsus-

pend”.

(b) What is meant by reinstalling a signal handler?

(c) Write about phase function. [6+5+5]

6. (a) What is region lock? What are the rules about the specification of the region

to be locked or unlocked? [3+5]

(b) Write a function to test for a locking condition.

Explain the following commands with syntax

(a) who

(b) date

(c) find

(d) wc [4x4=16]

2. Explain the following commands with syntax

(a) uniq

(b) grep

(c) tar

(d) join [4x4=16]

3. What is the advantage of having lseek be a separate system call, instead of passing

the starting offset to every read or write? What are the drawbacks? [12+4]

4. Explain the following system calls with syntax:

(a) alloca()

(b) setjmp()

(c) longjmp()

(d) exit() [4x4=16]

5. (a) What are the phases in signaling process? Explain what is meant by the

lifetime of a signal. [3+5]

(b) What is meant by signal catching function? What are the advantages of signal

function. [3+5]

6. (a) Explain in detail about fcntl( ) function.

(b) Write about Advisory locking versus mandatory locking.

Explain the following commands with syntax

(a) df

(b) umount

(c) mv

(d) find [4x4=16]

2. Explain the following commands with syntax

(a) uniq

(b) grep

(c) tar

(d) join [4x4=16]

3. What is the advantage of having lseek be a separate system call, instead of passing

the starting offset to every read or write? What are the drawbacks? [12+4]

4. Explain the following system calls with syntax:

(a) getrlimit ()

(b) setrlimit ()

(c) fork()

(d) wait() [4x4=16]

5. (a) What is signal function? Write and explain about the structure of signal

function. [3+5]

(b) What are the phases in signaling process? Explain what is meant by the

lifetime of a signal.

Explain the following commands with syntax

(a) wc

(b) umask

(c) ulimit

(d) mount [4x4=16]

2. What is the purpose of grep command? Explain the various options available with

the grep command with an example. [4+8+4]

3. (a) Briefly explain the file directories.

(b) Write in detail about Device drivers. [8+8]

4. What is meant by process termination? Explain the various types of process ter-

minations with suitable example. [4+8+4]

5. (a) What are the phases in signaling process? Explain what is meant by the

lifetime of a signal. [3+5]

(b) What is meant by signal catching function? What are the advantages of signal

function. [3+5]

6. (a) Explain in detail about the requirement of file locking mechanism.

(b) Explain in detail about fcntl( ) function.

Write short notes on the following:

(a) Process utilities

(b) Disk utilities [8+8]

2. What is the purpose of grep command? Explain the various options available with

the grep command with an example. [4+8+4]

3. Define file. Explain in detail about the various files. [4+12]

4. Write a program that calls fork and has the child create a new session. Verify

that the child becomes a process group leader, and that the child no longer has a

controlling terminal.

Explain the following commands with syntax

(a) ln

(b) mv

(c) rm

(d) ulimit [4x4=16]

2. Write a script that accepts a file name as argument and displays the last modifica-

tion time, if the file exists and a suitable message if it doesnt. [16]

3. Define system call. Explain in detail about the working and syntax of file structure

related system calls. [4+12]

4. What is meant by a process? Explain any four process related system calls with

syntax. [4+3x4=16]

5. (a) Write about the slow system calls. [8]

(b) Write about abort and system functions. [4+4]

6. (a) Explain in detail about the requirement of file locking mechanism.

(b) Explain in detail about fcntl( ) function.

Explain the following commands with syntax

(a) umask

(b) find

(c) mount

(d) unlink [4x4=16]

2. What is the purpose of Stream editor? Explain which option should be used to

place the contents of a file f1 after line. [4+12]

3. Explain the following system calls with syntax:

(a) mkdir()

(b) rndir()

(c) chdir()

(d) symlink() [4x4=16]

4. Write short notes on the following:

(a) Process termination

(b) Zombie process [8+8]

5. (a) What is signal handler? Explain how to install a signal Handler? [3+5]

(b) Write in detail about “Reliable signal Handling”. [8]

6. (a) With an example, Explain about the setting a lock. [3+5]

(b) With an example, Explain about clearing a lock.

Explain in detail about the UNIX Operating system structure. [16]

2. Explain the following commands with syntax

(a) sort

(b) cut

(c) pg

(d) comp [4x4=16]

3. Explain the following system calls with syntax:

(a) fseek()

(b) fgetc()

(c) getc()

(d) getchar() [4x4=16]

4. Suppose a process does not wish to block until its children terminate. How can it

ensure that child processes are cleaned up when they terminate? [16]

5. (a) Explain about the “features added to enhance signal reliability”. [8]

(b) Explain about “abort” and “kill” functions. [4+4]

6. (a) Write about Advisory locking versus mandatory locking.

(b) Write about file locking versus Record Locking.

Operating systems like UNIX provide services both for programs and users”. Jus-

tify this statement with suitable examples. [16]

2. (a) Explain the different approach taken by diff command to display file differ-

ences.

(b) Describe ‘comm’ command. Explain the output with -1,-2, or -3 options in

‘comm’ command. [8+8]

3. (a) Write a shell script which reports names and sizes of all files in a directory

(directory would be supplied as an argument to the shell script) whose size is

exceeding 1000 bytes. The filename should be printed in descending order of

their sizes. The total number of such files should also be reported.

(b) Write a C program to search for the word ‘exam’ in a given file, using Com-

mand line arguments. [8+8]

4. (a) What is a shell? What are the responsibilities of a shell?

(b) What are the different types of shells available in unix. [8+8]

5. Write a C program to print the type of specified file (Regular, device, directory)

[16]

6. (a) Write a program to illustrate the vfork function call.

(b) Write a program for signal implementation. [8+8]

7. Write a comparative study of adversary and mandatory locking

What is an operating system? Explain how UNIX fulfills more than that role.

Discuss suitable examples. [16]

2. Discuss the various backup utilities available in UNIX. Ilustrate with suitable ex-

amples. [16]

3. (a) Write a shell script to accept a string from the terminal and use ‘case’ to echo

a suitable message if the string does not have at least 10 characters using:

i. case

ii. expr

(b) Write a shell script to display the processes in the system five times every 30

seconds using:

i. while loop

ii. for loop. [8+8]

4. (a) Write a shell script which gets executed the moment the user logs in. It should

display the message “good morning/good afternoon/good evening” depending

upon the time at which the user logs in.

(b) Explain about here documents with an example. [8+8]

5. (a) Write and explain about hard and symbolic links.. give an example for each.

(b) Explain about file descriptors & i-node? [8+8]

6. Write a program which used both kill and raise functions. [16]

7. Write the differences between fcntl function and flock function.

. “Operating systems like UNIX provide services both for programs and users”. Jus-

tify this statement with suitable examples. [16]

2. (a) How to remove duplicate lines from a file using sort?

(b) How to count the number of ordinary files in home directory tree?

(c) Select lines 5 to 10 of a file in two ways. [5+5+6]

3. (a) Write a shell script for the following task.

The word ‘unix’ is present in only some of the files supplied as arguments to

the shell script. Your shell script should searched each of these files in turn

and stop at the first file that it encounters containing the word ‘unix’. This

filename should be displayed on the screen.

(b) Write a C program which receives file names as command line arguments and

display those filenames in ascending order according to their sizes. [8+8]

4. (a) Write a shell script which gets executed the moment the user logs in. It should

display the message “good morning/good afternoon/good evening” depending

upon the time at which the user logs in.

(b) Explain about here documents with an example. [8+8]

5. (a) Write and explain about hard and symbolic links.. give an example for each.

(b) Explain about file descriptors & i-node? [8+8]

6. Write the syntax of following functions. Explain each argument.

(a) kill

(b) raise

(c) alarm

(d) exit. [4+4+4+4]

7. (a) Write a C program to use a function lock test to test for a lock.

(b) Write about lockf function. [8+8]

Explain various commands available in UNIX for networking. Discuss suitable

examples. [16]

2. Which is the command used for ordering a file? Discuss all the options available

for this command. For every option explain with an example. [16]

3. (a) Write a shell script which will receive any number of filenames as arguments.

The shell script should check whether every argument supplied is a file or a

directory. If it is a directory it should be appropriately reported. If it is a

Filename then name of the file as well as the number of lines present in it

should be reported.

(b) Write a C program to simulate ‘tail’ command. [8+8]

4. (a) Write a shell script which gets executed the moment the user logs in. It should

display the message “good morning/good afternoon/good evening” depending

upon the time at which the user logs in.

(b) Explain about here documents with an example. [8+8]

5. Write the syntax of following system calls.

(a) open

(b) creat

(c) read

(d) write.