Question

You are given an array as below:
IFS=", " #set IFS to be a comma.

MYARRAY=(101,102,103,105)

Which of the following structure can be used to expand an array?

${MYARRAY[]}
${MYARRAY[?]}
${MYARRAY[@]}
${MYARRAY[!]}

Which of the following is a test statement that can be used with while or if or elif statements?

#Initialized variables are as below

i=0 #variable i initialized to be 0

[$i -lt 10]
{$i -lt 10}
($i -lt 10)
[i -lt 10]

Which of the following variable stores the first argument given to a shell program command?
#
2
1
3

You executed a command as below on a terminal

$grep -n "hello" myfile.txt

What is the value of exit status variable "?" if the command returns an empty output?
none
0
1
2

A variable '!' used by a program is used to store the number of argument to a shell command.
T/F

-f is an operator to check if a regular file exist in a directory. It is used as:

if test -f myfile.txt

then

echo "file exists"

else

echo "file does not exist"

fi

True

False

Answer 1

1.Which of the following structure can be used to expand an array?

Ans:

${MYARRAY[@]} //or you can also use ${MYARRAY[*]}

2.

Which of the following is a test statement that can be used with while or if or elif statements?

#Initialized variables are as below

i=0 #variable i initialized to be 0

Ans:

[$i -lt 10]

3.Which of the following variable stores the first argument given to a shell program command?

Ans: 1

#0 is used to store filename, # is used to count the arguments

4.You executed a command as below on a terminal

$grep -n "hello" myfile.txt

What is the value of exit status variable "?" if the command returns an empty output?

Ans: 1 #if pattern found, stus code will be 0

5.A variable '!' used by a program is used to store the number of argument to a shell command.

Ans: False. # to store the number of arguments '#' variable is used.

6.f is an operator to check if a regular file exist in a directory. It is used as:

if test -f myfile.txt

then

echo "file exists"

else

echo "file does not exist"

fi

Ans: True