Practice Exercises:
Exercise 1:
Write a shell script that prints "Shell Scripting is Fun!" on the screen.
Hint 1: Remember to make the shell script executable with the chmod command.
Hint 2: Remember to start your script with a shebang !
Exercise 2:
Modify the shell script from exercise 1 to include a variable. The variable will hold the contents of the message "Shell Scripting is Fun!".
Exercise 3:
Store the output of the command "hostname" in a variable. Display "This script is running on _______." where "_______" is the output of the "hostname" command.
Hint: It's a best practice to use the ${VARIABLE} syntax if there is text or characters that directly precede or follow the variable.
Exercise 4:
Write a shell script to check to see if the file "/etc/shadow" exists. If it does exist, display "Shadow passwords are enabled." Next, check to see if you can write to the file. If you can, display "You have permissions to edit /etc/shadow." If you cannot, display "You do NOT have permissions to edit /etc/shadow."
Exercise 5:
Write a shell script that displays "man", "bear", "pig", "dog", "cat", and "sheep" on the screen with each appearing on[…]”
Excerpt From: Cannon, Jason. “Shell Scripting: How to Automate Command Line Tasks Using Bash Scripting and Shell Programming”. Apple Books.
“Solutions to the Practice Exercises
Exercise 1:
#!/bin/bash
echo "Shell Scripting is Fun!"
Exercise 2:
#!/bin/bash
MESSAGE="Shell Scripting is Fun!"
echo "$MESSAGE"
Exercise 3:
#!/bin/bash
HOST_NAME=$(hostname)
echo "This script is running on ${HOST_NAME}."
Exercise 4:
#!/bin/bash
FILE="/etc/shadow"
if [ -e "$FILE" ]
then
echo "Shadow passwords are enabled."
fi
if [ -w "$FILE" ]
then
echo "You have permissions to edit ${FILE}."
else
echo "You do NOT have permissions to edit ${FILE}."
fi
Exercise 5:
#!/bin/bash
for ANIMAL in man bear pig dog cat sheep
do
“ echo "$ANIMAL"
done
Exercise 6:
#!/bin/bash
read -p "Enter the path to a file or a directory: " FILE
if [ -f "$FILE" ]
then
echo "$FILE is a regular file."
elif [ -d "$FILE" ]
then
echo "$FILE is a directory."
else
echo "$FILE is something other than a regular file or directory."
fi
ls -l $FILE
Exercise 7:
#!/bin/bash
FILE=$1
if [ -f "$FILE" ]
then
echo "$FILE is a regular file."
elif [ -d "$FILE" ]
then
echo "$FILE is a directory."
else
echo "$FILE is something other than a regular file or directory."
fi
ls -l $FILE
Exercise 8:
#!/bin/bash
for FILE in $@
do
if [ -f "$FILE" ]
then
echo "$FILE is a regular file."
elif [ -d "$FILE" ]
then
echo "$FILE is a directory."
else
echo "$FILE is something other than a regular file or directory."
fi
ls -l $FILE
done”
Excerpt From: Cannon, Jason. “Shell Scripting: How to Automate Command Line Tasks Using Bash Scripting and Shell Programming”. Apple Books.
