UNIX System Multiple choice Questions and Answers-UGC NET computer science question paper

1.	In UNIX, which of the following command is used to set the task priority ?
a.	init
b.	nice
c.	kill
d.	PS

Answer: (b).nice

2.	Which of the following flags are set when ‘JMP’ instruction is executed ?
a.	SF and CF
b.	AF and CF
c.	All flags
d.	No flag is set

Answer: (d).No flag is set

3.	Everything below the system call interface and above the physical hardware is known as ______.
a.	Kernel
b.	Bus
c.	Shell
d.	Stub

Answer: (a).Kernel

Answer: (b).Fair Preemptive Scheduling

5.	In Unix, how do you check that two given strings a and b are equal?
a.	test $a -eq $b
b.	test $a -equal $b
c.	test $a = $b
d.	both a and c

Answer: (d).both a and c

6.	The directory structure used in Unix file system is called
a.	Hierarchical directory
b.	Tree structured directory
c.	Directed acyclic graph
d.	Graph structured directory

Answer: (a).Hierarchical directory

7.	Which statement is not true about process 0 in the Unix operating system?
a.	Process 0 is called init process
b.	Process 0 is not created by fork system call
c.	After forking process 1, process O becomes swapper process
d.	Process 0 is a special process created when system boots

Answer: (a).Process 0 is called init process

8.	Which or the following commands would return process_id of sleep command?
a.	Sleep 1 and echo $?
b.	Sleep 1 and echo #
c.	Sleep 1 and echo $*
d.	Sleep 1 and echo $!

Answer: (b).Sleep 1 and echo #

9.	What does the following command do ? grep − vn "abc" x
a.	It will print all of the lines in the file x that match the search string "abc"
b.	It will print all of the lines in file x that do not match the search string "abc"
c.	It will print total no of the lines in file x that match the search string "abc"
d.	It will print the specific line numbers of file x in which there is a match for the string "abc"

Answer: (a).It will print all of the lines in the file x that match the search string "abc"

10.	The Unix Kernel maintains two key data structures related to processes, the progress table and the user structure. Which of following information is not the part of user
a.	File descriptor table
b.	System call state
c.	Scheduling parameters
d.	Kernel stack

Answer: (c).Scheduling parameters