1⟩ The statement z = 'expr 5 / 2′ would store which of the following values in z? a) 0 b) 1 c) 2 d) 2.5 e) 3
c) 2
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2⟩ What is the output of the following program? [ -n $HOME ] echo $? [ -z $HOME ] echo $? a) 0 1 b) 1 0 c) 0 0 d) 1 1
a) 0
1
3⟩ What is the output of the following program? x = 3; y = 5; z = 10; if [( $x -eq 3 ) -a ( $y -eq 5 -o $z -eq 10 )] then echo $x else echo $y fi a) 1 b) 3 c) 5 d) Error
b) 3
4⟩ The expression expr -9 % 2 evaluates to a) 0 b) 1 c) -1 d) 2
c) -1
5⟩ What is the output of the following program? b = [ -n $b ] echo $? [ -z $b ] echo $? a) 1 1 b) 2 2 c) 0 0 d) 0 1
c) 0
0
6⟩ What is the output of the following code os=Unix echo 1.$os 2."$os" 3.'$os' 4.$os a) 1.Unix 2.Unix 3.Unix 4.Unix b) 1.Unix 2.Unix 3.$os 4.Unix c) 1.Unix 2.Unix 3.Unix 4.$os d) 1.Unix 2.$os 3.$os 4.$os
b) 1.Unix 2.Unix 3.$os 4.Unix
7⟩ Create a new file "new.txt" that is a concatenation of "file1.txt" and "file2.txt"? a) cp file.txt file2.txt new.txt b) cat file1.txt file2.txt > new.txt c) mv file[12].txt new.txt d) ls file1.txt file2.txt | new.txt
b) cat file1.txt file2.txt > new.txt
8⟩ What will be output of following command $ echo "The process id is" $$$$ a) The process id is $$ b) The process id is $<pid>$<pid> c) The process id is <pid><pid> d) The process id is $$$$
c) The process id is <pid><pid>
9⟩ What is the return value ($?) of this code os = Unix [$osName = UnixName] && exit 2 [${os}Name = UnixName] && exit 3 a) 0 b) 1 c) 2 d) 3
d) 3
10⟩ Which of these is not a valid variable in bash a) __ (double underscore) b) _1var (underscore 1 var ) c) _var_ (underscore var underscore) d) some-var (some hyphen var)
d) some-var (some hyphen var)
11⟩ How do you print the lines between 5 and 10, both inclusive? a) cat filename | head | tail -6 b) cat filename | head | tail -5 c) cat filename | tail +5 | head d) cat filename | tail -5 | head -10
a) cat filename | head | tail -6
12⟩ What would be the current working directory at the end of the following command sequence? $ pwd /home/user1/proj $ cd src $ cd generic $ cd . $ pwd a) /home/user1/proj b) /home/user1/proj/src c) /home/user1 d) /home/user1/proj/src/generic
d) /home/user1/proj/src/generic
13⟩ Tell me which of the following commands allows definition and assignment of environment variables under bash a) env b) export c) environ d) setenviron
a) env
14⟩ The redirection 2> abc implies a) Write file 2 to file abc b) Write standard output to abc c) Write standard error to abc d) none of the mentioned
c) Write standard error to abc
15⟩ cmd 2>&1 > abc will a) Write file2 to file1 b) Write standard output and standard error to abc c) Write standard error to abc d) Write standard output to abc & standard error to monitor
d) Write standard output to abc & standard error to monitor
16⟩ From where would the read statement read if the following statements were executed? exec < file1 exec < file2 exec < file3 read line a) It would read all the files b) It would not read any files c) It would read all the files in reverse order d) It would read only file3
b) It would not read any files
17⟩ Which of these is the correct method for appending "foo" in /tmp/bar file? a) echo foo > /tmp/bar b) echo foo >> /tmp/bar c) echo foo | /tmp/var d) /tmp/bar < echo foo
b) echo foo >> /tmp/bar
18⟩ Executing cat /etc/password > /dev/sda as superuser will a) Write data into a regular file called /dev/sda b) Write data to the physical device sda c) Create a temporary file /dev/sda and write data to it d) None of the above
b) Write data to the physical device sda
19⟩ Which variable contains last background job process id a) $* b) $? c) $$ d) $!
d) $!
20⟩ The $ variables in a shell script context designates a) The runtime of the script b) Number of command line arguments c) PID of the shell running the script d) The exit status of the shell script
c) PID of the shell running the script
