Question 1

On executing a statement set -3+1
A)$1 would be -3
B)$1 would be -
C)$1 would be set
D)this command would result into an error

Accepted Answer

The command `set -3+1` is not a valid syntax for setting a variable in most programming or scripting languages, and it would likely result in an error. The `set` command is used in various shells to set or unset values of shell options and positional parameters, but the syntax provided does not conform to a valid use case.

Question 2

On executing the command Shift $v
A)the positional parameters would be shifted by the value of the variable v
B)the positional parameters would be shifted by 1
C)the positional parameters would not be shifted at all
D)this command would result into an error

Accepted Answer

The command `Shift $v` shifts the positional parameters to the left by the number of positions specified by the value of the variable `v`. If `v` is 2, for example, `$3` would become `$1`, `$4` would become `$2`, and so on.

Question 3

Which of the following shows the correct hierarchy of arithmetic operations in shell
A)(),**,* or /, + or -
B)(), **, *,/,+,-
C)(),**,/,*,+,-
D)(),/,% or *,- or +

Accepted Answer

D

Question 4

Which of the following is allowed in an arithmetic statement involving exprinstruction
A)[]
B){}
C)()
D)none of the above

Accepted Answer

The expr instruction in shell scripting and many programming languages allows the use of parentheses () for grouping in arithmetic expressions to dictate the order of operations.

Question 5

The statement z='expr 5/2' would store in z a value
A)2.5
B)3
C)2
D)0

Accepted Answer

The 'expr' command in Unix/Linux performs integer arithmetic, so '5/2' would result in 2 because it truncates the decimal part.

Question 6

The expression expr -7 % 2evaluates to
A)1
B)-1
C)-3.5
D)0

Accepted Answer

The modulo operation returns the remainder of the division of the first number by the second. In this case, -7 divided by 2 gives a quotient of -3 and a remainder of -1.

Question 7

The expression expr -2 % 7 evaluates to
A)2
B)-2
C)0
D)0.285

Accepted Answer

The modulo operation (%) returns the remainder of the division of the first number by the second number. In this case, -2 % 7 equals -2 because -2 divided by 7 equals 0 with a remainder of -2.

Question 8

Hierarchy decides which operator
A)is most important
B)is used first
C)is fastest
D)operates on largest numbers

Accepted Answer

Hierarchy in the context of operators determines the order in which operators are evaluated, or which operators are used first in expressions.

Question 9

The break statement is used to exit from
A)an if statement
B)a for loop
C)a program
D)none of the above

Accepted Answer

The break statement is used to exit from loops prematurely, including for loops, while loops, and do-while loops. It is not used to exit from an if statement or a program directly.

Question 10

An until loop ensures that the statement within the loop get executed
A)only once
B)atleast once
C)not even once
D)none of the above

Accepted Answer

The answer of An until loop ensures that the statement...

Question 11

Which option will be used with sort command to start sorting after the nth column of the (m+1)th field
A)-m.n
B)+m.n
C)+n.m+1
D)+(m+1).n

Accepted Answer

The correct option is B) +m.n, which specifies that sorting should start after the nth column of the (m+1)th field when using the sort command.

Question 12

Which command is used to terminate a process
A)shutdown
B)haltsys
C)cancel
D)kill

Accepted Answer

The "kill" command is used to terminate a process in Unix, Linux, and other Unix-like operating systems. It sends a signal to a process, allowing for graceful termination or immediate halt based on the signal specified.

Question 13

The command is used to compare the files is known as
A)comp
B)cmp
C)do
D)ccp

Accepted Answer

The command "cmp" is used in Unix, Linux, and similar operating systems to compare two files byte by byte, allowing users to see if they are identical or where the first difference occurs.

Question 14

The command which transcribes the standard input to the standard output and also makes a copy of the same in a file is
A)tee
B)tr
C)sort
D)grep

Accepted Answer

The "tee" command reads the standard input and writes it to both the standard output and one or more files, effectively duplicating its input.

Question 15

Which command is used to remove a directory
A)rd
B)rmdir
C)dldir
D)rdir

Accepted Answer

The correct command to remove a directory is "rmdir".

Question 16

Which of the following keys is used to replace a dingle character with new text
A)s
B)s.
C)r
D)c

Accepted Answer

The answer of Which of the following keys is used...

Question 17

Which command is used to extract a specific columns from the file
A)cat
B)cut
C)grep
D)paste

Accepted Answer

The "cut" command in Unix or Linux is used to extract specific columns from a file. It allows you to select portions of each line of a file and write the result to standard output.

Question 18

Which command sends the word count of the file infile to the newfile.
A)wcinfile>newfile
B)wcnewfile
C)wcinfile - newfile
D)wcinfile | newfile

Accepted Answer

The correct command to send the word count of the file "infile" to "newfile" is by using redirection. The command `wc infile > newfile` uses `wc` for word count on "infile" and `>` to redirect the output to "newfile".

Question 19

Which command is used to remove the read permission of the file 'note' from both the group and others?
A)chmodgo+r note
B)chmodgo+rw note
C)chmod go-x note
D)chmod go-r, 4-x note

Accepted Answer

The correct command to remove the read permission from both the group and others for the file 'note' is `chmod go-r note`. However, there seems to be a typo in the options provided. The closest correct option, despite the typo, is D, which attempts to remove read permission (though it incorrectly includes ", 4-x" which seems to be a formatting error or typo). The correct syntax without the typo should be `chmod go-r note`.

Question 20

Which command is used to concatenate all files beginning with the string 'emp' and followed by a non-numeric characters?
A)cat emp[!0-9]
B)more [emp][!0-9]
C)cat emp[x-z]
D)cat emp[a-z]

Accepted Answer

The command `cat emp[!0-9]` is used to concatenate files starting with 'emp' followed by any character that is not a numeric character (0-9), which matches the requirement.

Quiz 3: Unix Commands and Functions: Part B

On executing a statement set -3+1

On executing the command Shift $v

Which of the following shows the correct hierarchy of arithmetic operations in shell

Which of the following is allowed in an arithmetic statement involving exprinstruction

The statement z='expr 5/2' would store in z a value

The expression expr -7 % 2evaluates to

The expression expr -2 % 7 evaluates to

Hierarchy decides which operator

The break statement is used to exit from

An until loop ensures that the statement within the loop get executed

Which option will be used with sort command to start sorting after the nth column of the (m+1) th field

Which command is used to terminate a process

The command is used to compare the files is known as

The command which transcribes the standard input to the standard output and also makes a copy of the same in a file is

Which command is used to remove a directory

Which of the following keys is used to replace a dingle character with new text

Which command is used to extract a specific columns from the file

Which command sends the word count of the file infile to the newfile.

Which command is used to remove the read permission of the file 'note' from both the group and others?

Which command is used to concatenate all files beginning with the string 'emp' and followed by a non-numeric characters?