Fresh Awk Programming Interview Questions & Answers:

1. The command "awk '{if ("9″>"10″) print "google" else print "linux"}'"
a) will print "google"
b) will print "linux"
c) will generate syntax error
d) none of the mentioned

c) will generate syntax error
Explanation:
Semicolon is required just before the else statement to parse the statement.
Output:
root@ubuntu:/home/google# awk '{if ("9″>"10″) print "google" else print "linux"}'
awk: {if ("9″>"10″) print "google" else print "linux"}
awk: ^ syntax error
root@ubuntu:/home/google#

2. What is the output of this program?

#! /usr/bin/awk -f
BEGIN {
a=0
do {
print "google"
a++
} while (a<5)
}
a) "google" will print 4 times
b) "google" will print 5 times
c) nothing will print
d) syntax error

b) "google" will print 5 times
Output:
root@ubuntu:/home/google# ./test.awk
google
google
google
google
google
root@ubuntu:/home/google#

3. What is the output of this program?

#! /usr/bin/awk -f
BEGIN {
for(i=0;i<=5;i++) {
print i
i++
}
}
a) 0,2,4 will print
b) 1,3,5 will print
c) 1,2,3,4,5 will print
d) syntax error because i is not initialised

a) 0,2,4 will print
Output:
root@ubuntu:/home/google# ./test.awk
0
2
4
root@ubuntu:/home/google#

4. What is the output of this program?

#! /usr/bin/awk -f
BEGIN {
a=6
do {
print "google"
a++
} while (a<5)
}
a) nothing will print
b) "google" will print 5 times
c) "google" will print 4 times
d) "google" will print only 1 time

d) "google" will print only 1 time
Explanation:
Even the condition is false of do-while loop, the body is executed once.
Output:
root@ubuntu:/home/google# ./test.awk
google
root@ubuntu:/home/google#

5. What is the output of this program?

#! /usr/bin/awk -f
BEGIN {
a=5
while (a<5) {
print "google"
a++;
}
}
a) nothing will print
b) "google" will print 5 times
c) program will generate syntax error
d) none of the mentioned

a) nothing will print
Explanation:
The condition of while statement is false so commands inside the loop will not execute.
Output:
root@ubuntu:/home/google# ./test.awk
root@ubuntu:/home/google#

6. The next statement:
a) immediately stops processing the current record
b) go to the next record
c) both (a) and (b)
d) none of the mentioned

c) both (a) and (b)

7. The break statement:
a) jumps out of the innermost for loop
b) jumps out of the innermost while loop
c) jumps out of the innermost do-while loop
d) all of the mentioned

d) all of the mentioned

8. Which statement instructs gawk to stop processing the current data file?
a) next
b) nextfile
c) exit
d) exitfile

b) nextfile

9. If the argument is supplied to the exit statement:
a) its value is used as the exit status code for the awk process
b) syntax error will generate
c) exit returns status 0
d) exit returns status 1

a) its value is used as the exit status code for the awk process

10. Which statement skips over the rest of the loop body, causing the next cycle around the loop to begin immediately?
a) continue
b) break
c) next
d) none of the mentioned

a) continue

11. What is FNR?
a) FNR is the current record number in the current file
b) FNR is the number of fields in the current input record
c) FNR is an array contains the value of environment
d) none of the mentioned

a) FNR is the current record number in the current file

12. In awk, the built-in variable FS is:
a) input field seperator
b) output field seperator
c) record seperator
d) subscript seperator

a) input field seperator

13. RSTART is set by invoking the:
a) match function
b) index function
c) asort function
d) split function

a) match function

14. In awk program, the name of the array can not be same with the:
a) name of variable
b) value of the array element
c) both (a) and (b)
d) none of the mentioned

a) name of variable

15. What is the meaning of $ sign in awk programming?
a) the word following is the name of variable
b) we are referring to a field or column in the current line
c) $ sign is used for comment
d) none of the mentioned

b) we are refering to a field or column in the current line

16. Which one of the following is used by awk to control the conversion of numbers to string?
a) RS
b) OFMT
c) SUBSEP
d) RSTART

b) OFMT

17. What is the output of the program?

#! /usr/bin/awk -f
#This filename is text.awk
BEGIN {
print FILENAME
}
a) test.awk
b) program will print nothing
c) syntax error
d) fatal error

b) program will print nothing
Explanation:
The built-in variable FILENAME is the name of file that awk is currently reading and in this program there is no file listed on the command line.
Output:
root@ubuntu:/home/google# ./test.awk
root@ubuntu:/home/google#

18. Define the output of the program?

#! /usr/bin/awk -f
BEGIN {
a["linux","MCQ"]="google"
print a["linux","MCQ"]
}
a) google
b) linux MCQ
c) a["linux","MCQ"]
d) syntax error

a) google
Output:
root@ubuntu:/home/google# ./test.awk
google
root@ubuntu:/home/google#

19. What is the output of the program?

#! /usr/bin/awk -f
BEGIN {
a[1]="google"
a[2]="google"
for(i=1;i<3;i++) {
print a[i]
}
}
a) "google" will print 2 times
b) "google" will print 3 times
c) program will generate error becasue 2 array elements have the same value
d) program will generate syntax error

a) "google" will print 2 times
Output:
root@ubuntu:/home/google# ./test.awk
google
google
root@ubuntu:/home/google#

20. What is the output of the program?

#! /usr/bin/awk -f
BEGIN {
a["linux","MCQ"]="google"
print a["linux","MCQ"]
}
a) google
b) linux MCQ
c) a["linux","MCQ"]
d) syntax error

a) google
Output:
root@ubuntu:/home/google# ./test.awk
google
root@ubuntu:/home/google#

21. What is the output of the program?

#! /usr/bin/awk -f
BEGIN {
a[1,1]=0
a[1,2]=1
a[2,1]=2
a[2,2]=3
for(i=1;i<3;i++) {
for(j=1;j<3;j++) {
print a[i,j]
}
}
}
a) 0 1 2 3
b) 0 2
c) 1 3
d) syntax error

b) 0 2
Output:
root@ubuntu:/home/google# ./test.awk
0
2
root@ubuntu:/home/google#

22. Which one of the following is not true?
a) nawk is the new version of awk
b) gawk is the GNU version of awk
c) linux users have the gawk
d) nawk does not provide the additional capabilities in comparison of awk

d) nawk does not provide the additional capabilities in comparison of awk

23. An awk program can be run by:
a) including the program in the command that runs awk
b) putting it into a file and run with a command
c) running an executable awk script
d) all of the mentioned

d) all of the mentioned
Explanation:
The method used to run awk program depends on the program size and input files.

24. The print and printf statements can be told to send their output to other place except standard output, is called:
a) redirection
b) redistribution
c) reinsertion
d) none of the mentioned

a) redirection

25. In awk program, the statement "print" with no items:
a) is equivalent to "print $0″
b) prints the entire current record
c) both (a) and (b)
d) none of the mentioned

c) both (a) and (b)

26. Which one of the following is not true?
a) in typical awk program, all input is read either from standard input or specified files
b) awk language divides its input into records and fields
c) awk reads an input record and the record is automatically seperated by the interpreter into pieces called "fields"
d) the number of fields need to be a constant

d) the number of fields need to be a constant
Explanation:
The number of fields does not need to be a constant.

27. Which one of the following statement is not true about the format-control letters for printf statement in awk program?
a) "c" prints a number as an ASCII character
b) "d" prints a decimal integer
c) "h" prints an unsigned hexadecimal integer
d) "o" prints an unsigned octal integer

c) "h" prints an unsigned hexadecimal integer
Explanation:
"x" prints and unsigned hexadecimal integer

28. The command "awk {print $1} san.txt" will:
a) print the first line of file san.txt
b) print the first field of every line in san.txt
c) generate syntax error
d) none of the mentioned

b) print the first field of every line in san.txt

29. What is the output of the command awk 'BEGIN {printf "%cn",65}'
a) A
b) 65
c) syntax error
d) none of the mentioned

a) A
Explanation:
The ASCII value of A is 65.

30. Which one of the following is not true?
a) there are 3 types of constant expressions: numeric, string and regular
b) arithmetic operators are used to evaluate expressions
c) assignment expression is an expression that stores a value into a variable
d) comparison expressions does not compare strings for relationship

d) comparison expressions does not compare strings for relationship

31. Which command on the command line provides the same output as this executable awk script?

#! /usr/bin/awk -f
BEGIN {
print "google"
}
a) awk 'BEGIN {print "google"}'
b) awk 'print "google"'
c) awk 'print {google}'
d) none of the mentioned

a) awk 'BEGIN {print "google"}'

32. Concatenation is performed by:
a) writing expressions next to one another, with no operator
b) conditional operator
c) relational operator
d) matching operator

a) writing expressions next to one another, with no operator

33. All numeric values are represented within awk in:
a) double precision floating point
b) integer
c) exponential notation
d) fixed point

a) double precision floating point

34. What is the output of this program?

#! /usr/bin/awk -f
BEGIN {
print "20"<"9" ? "true":"false"
}
a) true
b) false
c) syntax error
d) none of the mentioned

a) true
Explanation:
The operands of relational operators are converted to, and compared as string if both are not numbers. Strings are compared by comparing the characters of each. Hence 20 is less then 9.
Output:
root@ubuntu:/home/google# chmod +x test.awk
root@ubuntu:/home/google# ./test.awk
true
root@ubuntu:/home/google#

35. The comparison expression "x ~ y" will true if:
a) x is not equal to y
b) the string x does not match the regular expression denoted by y
c) the string x matches the regular expression denoted by y
d) none of the mentioned

c) the string x matches the regular expression denoted by y